Bhagya

Reviewing Kerala Syllabus Plus One Chemistry Previous Year Question Papers and Answers Pdf Model 2019 helps in understanding answer patterns.

Kerala Plus One Chemistry Board Model Paper 2019

Question 1.
The symbol of the element with atomic number 118 is:
а) Uuu
b) Uuo
c) Ubu
d) Buo
Answer:
а) Uuu

Question 2.
The oxidation state of Cl in HClO. is
Answer:
+7

Question 3.
What is the bond order of 02 molecule?
Answer:
2

Question 4.
Blue Baby Syndrome is caused by excess of …………… in drinking water.
Answer:
NO₃^– (Nitrate)

Question 5.
Sodium hexa meta phosphate is commercially called:
Answer:
Calgon

Question 6.
Identify the Lewis acid among the following:
a) NH₃
b) H₂0
c) BF₃
d) Cl^–
Answer:
c) BF₃

Question 7.
Suggest a suitable method for the separation of a mixture of aniline and chloroform.
Answer:
Steam distillation

Answer any 10 questions from question number 8 to 20. Each carries 2 score. (10 × 2 = 20)

Question 8.
State and explain law of definite proportion.
Answer:
The law of definite proportion: The same compound always contains same elements in a fixed ratio by mass.
eg: Water always contains hydrogen and oxygen present in a ratio by mass as 2 :16 ie. 1 : 8

Question 9.
What are the two important defects of Rutherford’s nuclear model of atom?
Answer:
Defects of Rutherford’s nuclear model of atom are
i) It couldn’t explain the electronic structure of atom.
ii) It couldn’t explain the stability of an atom.

Question 10.
Give the reason for the deviation of real gases from the ideal gas behaviour.
Answer:
Two faulty assumptions in kinetic theory of gases.
a) There is no force of attraction between the gas molecules.
b) Volume of a gas molecule is negligible compared to the volume of the gas.

Question 11.
Differentiate between extensive and intensive properties with su itable examples.
Answer:

• Extensive properties are those properties which depend upon mass, eg . mass, volume, internal energy, entropy, etc.
• Intensive properties are those properties which are independent of mass, eg: pressure, temperature.

Question 12.
Justify the position of hydrogen in the periodic table.
Answer:
Hydrogen resembles both with alkali metals and halogens. Hydrogen has electronic configuration 1s1 as similar to alkali metals. It loses one electron to form unipositive ions as that of alkali. It can also gain electron to form uninegative ion as that of halogen.

Question 13.
Give the IUPAC name of the following compounds:

Answer:

Question 14.
a) How will you prepare H₂O₂ in the laboratory?
b) Draw the structure of H₂O₂ molecule.
Answer:
a) Acidifying barium peroxide with H2S04 and removing excess water by evaporation under reduced pressure gives hydrogen peroxide.

open book like structure or lap top structure.

Question 15.
Suggest a method to convert ethyne to benzene.
Answer:
By passing ethyne through a hot iron tube at 873 K

Question 16.
How will you prepare water gas and producer gas?
Answer:
Water gas is produced by passing steam over red hot coke.

Producer gas (a mixture of (CO & N₂) is prepared by passing air over red hot coke.

Question 17.
Account for the following:
a) H₂O is a liquid while H₂S is a gas at room temperature.
Answer:
Due to the presence of inter molecular hydrogen bonds H₂O is a Ijquid. But in H₂S there is no hydrogen bond.
(This is because, H₂O has intermolecular hydrogen bond between it’s molecule (H-O-H——H-O-H) while H₂S has weak Van Der Wals forces between it’s molecule. Hence the molecules of H₂O are strongly packed than H₂S, thus water is at liquid state at room temperature)

b) BeCl₂ molecule has zero dipole moment.
Answer:
In BeCl₂ the dipole moments in equal and opposite direction so it cancel each other.
Cl – Be – Cl

Question 18.
When sodium metal dissolves in liquid ammonia it gives a deep blue coloured solution. Explain the reason.
Answer:
The blue colour of the solution is due to the ammoniated electron which absorbs energy in the visible region of light and thus imparts blue colour to the solution.
M + (x + y)NH₃ → [M(NH₃)_x]^– +[e(NH₃)_y]^–

Question 19.
Illustrate common ion effect using an example.
Answer:
Common ion effect is the suppression of dissociation of a weak electrolyte by the addition of a strong electrolyte containing a common ion.
eg. Dissociation of NH₄Cl is suppressed by adding NH₄OH to the solution, (identification of group III in salt analysis)

Question 20.
Illustrate Markovnikov’s rule taking the example of propene.
Answer:
Markonikov’s rule: The negative part of the addentum moves to the a carbon atom which contains less number of hydrogen.

Answer any 7 questions from question number 21 to 29. Each carries 3 score. (7×3 = 21)

Question 21.
Ah organic compound contain the elements C, H and O in the composition C = 54. 24%, H=9.05% and 0=36.71%.If the molecular mass of the compound is 88 u, What is the molecular formula of the compound? (3)
Answer:
Img 8
Empirical formula = C₂H₄O
Empirical formula mass = 12 × 2 + 4 × 1 + 16
= 24 + 4 + 16
= 44
Molecular mass = 88 MF = (EF) × n
\(\frac{\text { Molecular mass }}{\text { Empirical formula mass }}\) = n = \(\frac{88}{44}\) = 2
Molecular formula = (C₂H₄O)₂ = C₄H₈O₂

Question 22.
a) Write the general outer electronic configuration of d-block elements. (1)
Answer:
ns¹² (n-1) d^1-10 np^1-6

b) The first ionisation enthalpy of sodium is lower than that of magnesium but it’s second ionization enthalpy is higher than that of magnesium. Explain. (2)
Answer:
₁₁Na – 1s² 2s² 2p⁶ 3s¹
Removing one electron requires less energy because by removing one electron it will get stable electronic configuration. Hence first IE of Na is lower. Na+ has stable electronic configuration with completed octet as
Na⁺ – 1 s² 2s² 2p⁶
Mg – 1s² 2s² 2p⁶ 3s²
In Na⁺ force of attraction is more and size is less than Mg. So IE₂ of Na is more than Mg.

Question 23.
a) Give two similarities between lithium and magnesium (2)
Answer:
1. Both Li and Mg are harder
2. Both Li and Mg combine with N₂ to form corresponding nitride Li₃N and Mg₃N₂
3. Li and Mg react slowly with water.
4. LiCl & MgCl₂ are deliquescent.

b) When carbon dioxide is passed through lime water, milkiness appears. Give equation for the above reaction. (1)
Answer:
Ca(OH)₂ + CO₂ → CaCO₃ + H₂O

Question 24.
Complete the following reactions,

Answer:

Question 25.
a) Define Dalton’s law of partial pressures. (1)
Answer:
The law states that the total pressure of a mixture of non reacting gases is equal to the sum of partial pressures of component gases.

b) Density of a gas was found to be 5.59 K at 27° C and 2 bar pressure. Calculate it’s molecular mass.
(R = 0.083 L atm / mol /K) (2)
Answer:
PV = nRT

Question 26.
Balance the following redox reaction using oxidation number or ion electron method in acidic medium.
Fe²⁺ + Cr₂O²⁺₇ → Fe³⁺ + Cr^3-
a) Explain the bonding in diborane. (2)
b) How will you convert diborane to inorganic benzene? (1)
Answer:
Oxidation number method
1. Skeletal equation is
Fe²⁺ + Cr₂O²⁺₇ → Fe³⁺ + Cr^3-
2. Calculate increase or decrease inn oxidation no.

Question 27.
a) Explain the bonding in diborane.
Answer:
Diborane is an electron deficient compound. In this compound a special type of 3 centered 2 electron bond is formed in addition to 2 centered 2 electron bond. This 3 centered 2 electron bond is also known as bridge bond or banana bond.

In this compound each Boron has 3 electron and each hydrogen atom has one electron ie., a total of 12 electrons. But with these 12 electrons 8 bonds have to be formed. So a Bridge bond is formed between twp boron atom and one hydrogen atoms using 2 electrons.

b) How will you convert diborane to inorganic benzene.
Answer:
3B₂H₆ + 6NH₃ → 3B₂H₆.2NH₃ → 2 B₃N₃H₆ + 12 H₂

Question 28.
Calculate the enthalpy of formation of methane from the following data: (3)

Answer:

Reviewing Kerala Syllabus Plus One Chemistry Previous Year Question Papers and Answers Pdf Model 2020 helps in understanding answer patterns.

Kerala Plus One Chemistry Board Model Paper 2020

PART A

Answer any 7 questions from 1 to 9. Each carries 1 score. (7 × 1 = 7)

Question 1.
In hydrogen spectrum, the series of lines appearing in Ultra violet region are called ……….
(a) Balmer line
(b) Lyman line
(c) Pfund line
(d) Bracket line
Answer:
(b) Lyman series

Question 2.
Conjugate base of a strong acid is
(a) a weak base
(b) a strong base
(c) neutral
(d) a weak acid
Answer:
(a) a weak base

Question 3.
Which of the elements show least value of ionization energies in each periods?
(a) Alkaline earth metals
(b) Alkali metals
(c) Noble Gases
(d) Halogens
Answer:
(b) Alkali metals

Question 4.
Which Graph does not represent Boyle’s law?

Answer:

Question 5.
Which one of the following is a common component of photochemical smog?
(a) O₃
(b) CO
(c) CO₂
(d) CH₂
Answer:
(a) O₃

Question 6.
Boric acid is polymeric due to
(a) Its acidic nature
(b) The presence of H bond
(c) Its monobasic nature
(d) Geometry
Answer:
(b) The presence of H bond

Question 7.
In ………… reaction an element in one oxidation state is simultaneously oxidized and reduced.
Answer:
Disproportionation reaction

Question 8.
Delocalization of electrons involving a bond is known as …………..
Answer:
Hyperconjugation

Question 9.
The hydrocarbon which give benzene when pass¬ing through a red hot iron tube is
Answer:
Ethyne or acetylene

PART B

Answer any 10 questions from 10-22. Each carries 2 scores. (10 × 2 = 20)

Question 10.
Development of periodic table have made the study of elements and their compounds easier.
Answer:
1. The physical and chemical properties of the elements are periodic functiond of their atomic numbers.
2. Ununquadium

Question 11.
Irrespective of the source, pure sample of CO₂ always yields 27.27% mass of carbon and 72.72% mass of oxygen.
(a) Which law is illustrated here? (1)
(b) State the law. (1)
Answer:
(a) Law of Definite proportion
(b)The same compound always contains same elements in definite proportion by mass.

Question 12.
Give reason for the following:
(a) The first ionization enthalpy of oxygen is smaller compared to nitrogen. (1)

Answer:
(a) Electronic configuration of N – 1s² 2s² 2p³
Completely half filled orbitals are extra stable. So more energy is needed to remove the valence electron. IE is high.
Electronic configuration of O – 1s² 2s² 2p⁴

(b) Electron gain enthalpy of F is less than that of Cl. (1)
Answer:
In the case of F the electron to be added is to 2p orbital. 2p orbital is small and occurs repulsion. In Cl atom the electron to be added is to 3p orbital. 3p is larger than 2p and repulsion is less. So Cl is with more electron affinity than Flourine.

Question 13.
Density of a gas at 27°C and 1 atm is 256 g/L. Calculate its molar mass [IR = 0.081 L atm mol^-1 k^-1]. (2)
Answer:
M = \(\frac{dRT}{P}\). P = 1 atm, R = 0.0821, T = 27°C = 300k
d = 256 g/L
= \(\frac{256 \times 0.0821 \times 300}{1}\) = 6305.28 g

Question 14.
Classify the following properties into extensive and intensive.
(Density, Enthalpy, Specific heat capacity, Entropy)
Answer:
Tablee

Question 15.
(a) The water solutions of the ionic compounds KCl, CH₃COOK and NH₄Cl show different pH value.
Identify the acidic, basic and neutral solution among these. (1)
Answer:
KCl gives neutral solution with pH = 7 because it is formed from strong base KOH and strong acid HCl.
CH₃COOK – basic pH > 7. Because it is formed from strong base KOH and weak acid CH₃COOH.
NH₄Cl → acidic pH < 7 because it is formed from weak base NH₄OH and strong acid HCl.

(b) What is ionic product of water? (1)
Answer:
Ionic product of water Kw for the reaction is

It is the product of the molar concentration of H+ and OH’ ions in water.

Question 16.
H₂O₂ is an important chemical.
(a) Give a method to prepare H₂O₂. (1)
(b) Represent the structure of H₂O₂. (1)
Answer:

Question 17.
Litium shows a diagonal relationship with magnesium.
Give any two similarity between Li and Mg. (2)
Answer:
1. They are hard
2. They do not form super oxides.

Question 18.
Calculate the wave number radiation due to transition of an electron from 4th to 2nd orbit.
(R_H = 109677 cm^-1).
Answer:

Question 19.
Draw the Newman’s projection of the clipsed and staggered conformation of ethane.
Answer:

Question 20.
Diborane is an electron deficient compound.
(a) Name the special bonds that present in diborane.
(b) How will you convert diborane into inorganic benzene?
Answer:
a. Banana bond or 3 centred – 2e bond
b. By reacting Ammonia with diborane inorganic benzene is formed.
3B₂H₆ + 6NH₃ → 2B₃N₃H₆ + 12H₂

Question 21.
What happen when
(a) Borax is heated strongly. (1)
Answer:
(a) Sodium meta borate and Boric anhydride is formed.

Or
On heating Borax first loses water molecules and swells up. On further heating it.turns into a transparent liquid which solidifies into glass like material known as borax bead.

(b) Boric acid is added to water. (1)
Answer:
When boric acid is added to water it act as Lewis acid by accepting electrons from a hydroxyl ion. B(OH)3 + 2HOH [B(OH)4]’ + H30+

Question 22.
Give the structure of the following compound:
(a) 4-Chloro-2-Methyl Pentane (1)
(b) 4-hydroxy pentan – 1- oic acid. (1)
Answer:

Answer any 7 questions from 23-31. Each carries 3 scores. (7 x 3 = 21)

Question 23.
(a)What is atomic mass unit (amu)? (1)
Answer:
1 amu = 1/12 th of a mass of a C-12 atom.

(b)KClO₃ on heating decomposes to KCl and O₂. Calculate the mass of O₂ produced by heating 50 gm KClO₃.
(Hint. 2KClO₃ → 2KCl + 3O₂)
Answer:
2KClO₃ → 2KCl + 3O₂
2 × 122.5g → 2 × 74.55 + 3 ×32
245.g KClO₃ → 96g O₂
1g KClO₃ → \(\frac{96}{245}\) g O₂
50g KClO₃ → × 50 = 19.58g

Question 24.
(a) Classify the following molecule according to the type of hydrogen bond H₂O, O-nitrophenol.
Answer:
Water – Inter molecular H – Bonding.
O – nitro phenol – Inter molecular H – bonding.

(b) NF₃ and NH₃ show dipole moment. But the dipole moment of NF₃ is less than that of NH₃. Why? (2)
Answer:

The orbital dipole due to lone pair is in the opposite direction with the resultant dipole moment of the N-F bonds.
So dipole moment is less.

The orbital dipole due to lone pair is in the same direction with the resultant dipole moment of the N- H bonds.
So net dipole moment is more.

Question 25.
(a) Give Vander Waal’s equation for ‘n’ mole of a gas. (1)
Answer:
(P – \(\frac{n^2 a}{v^2}\))(v – nb) = nRT
P – Pressure
a, b – vanderWaals constant
n – no. of moles
v – volume
T – temperature
R – Universal gas constant

(b) Write four postulates of kinetic theory of gases. (2)
Answer:
1. Gases consists of large no. of minute particles called molecules.
2. Particles are always in constant random motion.
3. During their motion they collide with each other and also with the walls of the container. These collisions results pressure.
4. Collisions of gas molecules are perfectly elastic.

Question 26.
(a) Give the criteria for spontaneity of a process in terms of free energy change (∆G). (1)
(b) How it is related to the enthalpy and entropy of a system? (1)
(c) What happens to the entropy during the following changes?
(i) A liquid crystallises into a solid.

Answer:
(a) For a spontaneous process ∆G should be -ve.
(b) ∆G = ∆H – T∆S
(c) 1. ∆S = -ve i.e. decreases
2. ∆S = +ve i.e. increases

Question 27.
(a) Using stock notation represent the following compounds:
(i) SnO₂
(ii) Cr₂O₃ (1)
Answer:
(i) Sn(IV)O₂
(ii) Cr₂(III)O₃

(b) In the reaction
2Cu₂O(S) + 2CU₂S(S) → 2CU(S) + SO₂
(i) Subtance oxidized
(ii) Subtance reduced
(iii) Oxidising agent
(iv)Reducing agent (2)
Answer:
(i) S is oxidised
(ii) Cu is reduced
(iii) Cu₂O oxidising agent
(iv) Cu₂S reducing agent

Question 28.
(a) Write the name of any one salt responsible for the permanent hardness of water. (1)
Answer:
(a) MgCl₂ or CaCl₂ or CaSO₄ or MgSO₄

(b) Explain one chemical method for removing per-manent hardness of water. (1)
Answer:
(1) Calgons process
Hard water is allowed to pass through Calgon. i.e. Sodium hexametaphosphate (Na6P6018) (2) Add washing soda to hard water.

(c) Suggest a disadvantages of hard water. (1)
Answer:
Soap do not lather in hard water.
Scales are formed in the boilers.

Question 29.
(a) What is plaster of paris? (1)
(b) Write the chemical equation showing the preparation of plaster of paris from Gypsum. (1)
(c) What is dead burnt plaster? (1)
Answer:
(a) CaSO₄.1/2 H₂O

Question 30.
(a)Consider the reaction given below:

(i) Identify the product X.
(ii) Name the reaction.
Answer:

(i) X= 1-Bromopropane
(ii) Anti markonikov’s addition
or
Peroxide effect
or
Kharash effect

(b) Complete the following reaction:

Answer:
CaC₄ + 2H₂0 → C₂H₂ + Ca(OH)₂

Reviewing Kerala Syllabus Plus One Chemistry Previous Year Question Papers and Answers Pdf Model 2021 helps in understanding answer patterns.

Kerala Plus One Chemistry Board Model Paper 2021

Answer any 6 questions from 1 to 12. Each carries 2 scores. (6 × 2 = 12)

Question 1.
State Hund’s rule of maximum multiplicity.
Answer:
Pairing occurs only after all the orbitals are completely half filled.

Question 2.
Calculate the de-Broglie wavelength associated with an electron with velocity 2.05 × 10⁷ ms^-1.
Answer:
de-Broglie wavelength = \(\frac{h}{m v}\)
= \(\frac{6.626 \times 10^{-34}}{9.1 \times 10^{-31} \times 2.05 \times 10^7}\)
= 3.55 × 10^-11 = 35.5

Question 3.
Based on VSEPR theory predict the shape of H₂O and NH₃.
Answer:
H₂O – bent or V Shape
NH₃ – Tetra hedral

Question 4.
Real gases do not follow gas laws perfectly under all conditions. Why?
Answer:
Due to two faulty assumptions in kinetic theory

• There is no force of attraction between the gas molecules.
• The volume of a gas molecule is negligible compare to the volume of a gas.

Question 5.
State the first law of thermodynamics.
Answer:
Energy can neither be created nor be destroyed.

Question 6.
Give the relation between k_p and k_c for the reaction given below.
2NOCl(g) → 2NO(g) + Cl₂(g)
Answer:
K_p = K_c . (RT)An
(An = no of moles of gaseous pdt – no of moles of gaseous reactant)
= 3 – 2 = 1
K_p = K_c. (RT)
K_p = K_c.RT

Question 7.
Classify the following into Lewis acids and Lewis bases.
(i) H₂O
(ii) NH₃
(iii) BCl₃
(iv) H⁺
Answer:
Lewis acids : – BCl,, H⁺
Lewis bases : NH₃, H₂O.

Question 8.
Write any two anomalous behaviuor of Li.
Answer:
(i) Li is very hard
(ii) Li forms monoxide

Question 9.
Givethe IUPAC name of the following
(A) CH₃ – CH = CH – CH₂ – CH₂ – COOH
(B)

Answer:
(A) Hex-4-en-1-oicacid
(B) Cyclohex-2-en-1-ol

Question 10.
Write any two chain isomers of a molecule having molecular formula C₅H₁₂.
Answer:

Question 11.
Name the following reaction

Answer:

Question 12.
Cyclopenta dienyl anion is aromatic. Why?
Answer:
Because it is planar, cyclic, conjugated and contains huckels no. of electrons.

Answer any 8 questions from 13 to 28. Each carries 3 scores. (8 × 3 = 24)

Question 13.
(i) State the law of definite proportion. (2)
Answer:
The same compound always contains same elements in a fixed ratio by mass.

(ii) Define limiting reagent of a reaction. (1)
Answer:
The reactant which is completely used up in the reaction.

Question 14.
(i) What is atomic mass unit? (1)
Answer:
amu = \(\frac{1}{12}\) th of a C – 12 atom

(ii) Calculate the number of atoms in each of the following:
(A) 52 mole of Ar
(B) 52 g of He (2)
Answer:
(A) 52 mole of Ar.
= 52 × 6.022 × 10²³ no.of Ar atoms 52

(B) 52 g of He = \(\frac{52}{4}\) × 6.022 × 10²³ no. of atoms.

Question 15.
(i) Which of the following ion is not isoelectronic with Ne atom.
(a) O^–
(b) Na⁺
(c) Al³⁺
(d) Mg²⁺ (1)
Answer:
(a) O^–

(ii) Explain why Na⁺ ion is smaller than Na atom.(2)
Answer:
In Na+ ion 11 proton attracts 10 electron so the size contracts. In Na 11 proton attracts 10 electron. So the size is large.

Question 16.
(i) Consider the process.

Which is greate IE₂ or IE₁? Justify. (2)
Answer:
IE₂ is greater.
IE₁ is the energy to remove one electron and attain stable electronic configuration. So it is low.
IE₂ is the energy needed to remove one electron from stable electronic configuration. So it is high.

(ii) Electron gain enthalpy of F is less than that of Cl. Why? (1)
Answer:
In F the electron enters to 2p orbital. But in Cl the enters to 3p orbital 2p is smaller compared to 3p and the electron repulsion is more in F than Cl.

Question 17.
(i) Explain the covalent character of LiCl using Fajan’srule. (1)
Answer:
Smaller the cation, large the anion more is the covalent character.

(ii) Write any two differences between sigma (σ) bond and pi(π) bond. (2)
Answer:

σ bond	π bond
Strong bond	Weak bond
By axial overlap	By sidewise overlap

Question 18.

(i) Name of the gas low shown by the above graph.
Answer:
Boyle’s law

(ii) A vessel 120 mL capacity contains a certain amount of gas at 35°C and 1.2 bar pressure. The gas is transffed to another vessel of volume 180 mL at 35°C. What would be its pressure?
Answer:
From Boyle’s law,
P₁V₁ = P₂V₂
Here P₁ = 1.2 bar, V₁ = 120 mL, V₂ = 180 mL,
P₂ = ?
1.2 × 120 = P₂ × 180
P₂ = 1.2 × 120/180 = 0.8 bar

Question 19.
(i) Write the van der Waal’s equation for ‘n’ mole of a gas. (1)
Answer:
(P + \(\frac{n^2 a}{V^2}\)) (V – nb) = nRT

(ii) State any four postulates of kinetic theory of gases. (2)
Answer:
(1) Gas consists of large number of minute particles called molecules.
(2) Molecules are always in random motion.
(3) During their motion they collide with each other this creates pressure.
(4) As the temperature increase K.E. also increases.

Question 20.
(i) Which among the following is an intensive property:
(a) Mass
(b) Volume
(c) Enthalpy
(d) Temperature (1)
Answer:
(d) Temperature

(ii) State and explain Hess’s law of constant heat summation. (2)
Answer:
The total enthalpy change for a process is same whether it lakes place in single step or several step.

Question 21.
(i) Define the Lattice enthalpy. (1)
Answer:
It is the enthalpy change when 1 mole of a compound is formed from its constituent ions.

(ii) Draw the Born-Haber cycle for the calculation of lattice enthalpy of NaCl. (2)
Answer:
Born-Haber cycle for the formation of NaCl

S – Sublimation energy
D – Dissociation energy
IE – Ionisation energy
EA- Electron gain enthalpy /electron affinity
U – Lattice energy
∆H_f – Enthalpy of formation

Question 22.
(i) The oxidation state of Mn in KMnO₄ is …….. (1)
Answer:

(ii) Identify the element undergoing disproportionation reaction in the following. (2)
2H₂O₂(aq) → 2H₂O(6) + O₂(g)
Answer:
Assign the oxidation number of each element

The element undergoing disproportionation reaction is oxygen in H₂O₂.

Question 23.
Balance the following equation by the half reaction method in acidic medium. (3)
Fe²⁺_(aq) + CrO^2-_7(aq) → Fe³⁺_(aq) + Cr³⁺_(aq) (3)
Answer:
Balance the equation by half reaction
Fe²⁺ + Cr₂O^2-₇ → Fe³⁺ + Cr³⁺
Step I : Fe²⁺ → Fe³⁺
Cr₂O^2-₇ → 2Cr³⁺

Step II : Balancing atoms other than oxygene and hydrogen
Fe²⁺ → Fe³⁺
Cr₂O^2-₇ → 2Cr³⁺

Step III : Balancing oxygen and hydrogen by adding H₂O and H⁺.
Fe²⁺ → Fe³⁺
Cr₂O^2-₇ + 14H⁺ → 2Cr³⁺ + 7H₂O

Step IV: Adding electrons to balance charges
Fe²⁺ → Fe³⁺ + e^–
Cr₂O^2-₇ + 14H⁺ + 6e → 2Cr³⁺ + 7H₂O

Step V: Equalising the no. of electrons in both
6Fe²⁺ → 6Fe³⁺ + 6e^–
Cr₂O^2-₇ + 14H⁺ + 6e → 2Cr³⁺ + 7H₂O

Step VI: Adding the two half reactions
6Fe²⁺ Cr₂O^2-₇ + 14H⁺ → 6Fe³⁺ + 2Cr³⁺ + 7H₂O

Question 24.
(i) Write the name of one salt responsible for the permanent hardness of water. (1)
Answer:
CaCl₂, CaSO₄, MgCl₂, MgSO₄

(ii) Explain any one method used for the removal of permanent hardness of water. (2)
Answer:
Add washing soda to hard water.

Question 25.
(i) Write the name of any two electron rich hydrides. (1)
Answer:
NH₃, PH₃,HCl

(ii) Explain with suitable chemical equation, why hydrogen peroxide is stored in waxlined glass or plastic vessel in dark. (2)
Answer:
H₂O₂ reacts with silica and decomposes easily in presence of light.
H₂O₂ → H₂O + O₂

Teachers recommend solving Kerala Syllabus Plus One Zoology Previous Year Question Papers and Answers Pdf Board Model Paper 2020 to improve time management during exams.

Kerala Plus One Zoology Board Model Paper 2020 with Answers

I. Answer any 3 questidns from 1-5. Each carries 1 score. (3 × 1 = 3)

Question 1.
The taxonomic aid used for identification of plants and animals based on the similarities and dissimilarities.
a) Manuals
b) Monogrpah
c) Key
d) Flora
Answer:
c) Key

Question 2.
Identify the given word pair relationship and fill in the blanks.
Cockroach – Malpighian Tubules
Amphioxus – _______
[Nephridia, Atennal glands, Green glands, Protonephridia]
Answer:
Protonephridia

Question 3.
In a protein molecule amino acids are linked by .
a) Glycosidic bond
b) Hydrogen bond
c) Peptide bond
d) Diester bond
Answer:
c) Peptide bond

Question 4.
In human being the sound is produced by
a) Pharynx
b) Larynx
c) Trachea
d) Bronchi
Answer:
b) Larynx

Question 5.
Pick the odd one out:
a) Pila
b) Nereis
c) Sepia
d) Loliga
Answer:
b) Nereis

II. Answer any 9 questions from 6 to 16. Each carries 2 scores. (9 × 2 = 18)

Question 6.
Observe the picture A and B.

a) Identify the tissues A and B.
b) Write any two features of A and B.
Answer:
a) A-Skeletal muscle or striated muscle
B-Smooth muscle or Non striated muscle

(b)

Skeletal muscle	Smooth muscle
They have striated in appearance	They are smooth in appearance
They are voluntary muscle	They are involuntary muscles

Question 7.
In an epithelium specialized junctions provide both structural and functional links between its individual cells. Identify any two types of cell junctions and their functions.
Answer:
1) Tightjunction

2) Gap junction
Tig ht junctions help to stop substances from leaking across a tissue. Gap junction helps the cells to communicate with each other by connecting the cytoplasm of adjoining cells and involved in rapid transfer of ions.

Question 8.
The mucus and bicarbonates present in gastric juice plays an important role in the protection of mucosal epithelium. Explain.
Answer:
The mucus and bicarbonates present in gastric juice protect the stomach wall from the action of HCI

Question 9.
Differentiate between
a) Apoenzyme and Coenzyme
b) Lyases and Ligases
Answer:
a) Apo enzyme : Protein part of the enzyme Co-enzyme : Non protein part of the enzyme

b) Lyases : Enzymes that catalyse removal of groups from substrates by mechanisms other than hydrolysis leaving double bonds.
Ligase: Enzymes catalysing the linking together of two compounds, e.g., enzymes which catalyse joining of C-O, C-S, C-N, P-0 etc. bonds.

Question 10.
Observe the picture.

a) Name the class to which this animal belongs.
b) Write any two characteristic features of this class.
Answer:
a) Class: Reptilia

b) i) They are mostly terrestrial animals and their body is covered by dry and cornified skin, epidermal scales or scutes ii) They do not have external ear openings.

Question 11.
a) Write any two enzymes present in succus entericus.
b) Write the functions of these enzymes.
Answer:
a) Maltase, Lactase

b) Maltase -It is involved in the conversion of maltose into two glucose molecules.
Lactase- It is involved in the conversion of Lactose into two glucose and Galactose.

Question 12.
a) What is normal respiratory rate?
b) Name an instrument used for measuring volume of air.
c) Mention its clinical significance.
Answer:
a) 12-16 times/minute
b) Spirometer
c) It is used to analyse the pulmonary function

Question 13.
Identify two wrong statements among the following and correct it.
a) Plasma without the clotting factors is called serum.
b) RBC is multinucleated in Human.
c) Neutrophils, Lymphocytes and Basophils are granulocytes.
d) Neutrophils and Monocytes are phagocytic cells.
Answer:
b) RBCs are devoid of nucleus
c) Neutrophils, eosinophils and basophils are agranulocytes.

Question 14.
a) Name any two synovial joints in our body,
b) Where is it located?
Answer:
a) Ball and socket joint, hinge joint

b) Ball and socket joint- It is located between humerus and pectoral girdle. Hinge joint It is located in knee joint

Question 15.
Fill up the table using appropriate terms.

Glands	Hprmones	Disease
Pitutary gland	a) _____	Diabetes insipidus
Pancreas	Insulin	b) _____
c) _____	Thyroxin	Cretinism
d) _____	Growth Hormone	Dwarfism

Answer:
a) Vasopressin
b) Diabetes mellitus
c) Thyroid gland .
d) Pituitary gland

Question 16.
ANF is a regulatory mechanism in kidney functioning,
a) Expand-ANF
b) Which part of the body secrete ANF?
c) Explain the regulatory mechanism.
Answer:
a) Atrial Natriuretic factor

b) Atrial wall of Heart

c) An increase in blood flow to the atria of the heart can cause the release of Atrial Natriuretic Factor (ANF). ANF can cause vasodilation (dilation of blood vessels) and thereby decrease the blood pressure. ANF mechanism acts as a check on the renin-angiotensin mechanism

III. Answer any 3 questions from 17 to 20. Each carries 3 scores. (3 × 3 = 9)

Question 17.
Observe the figure.

a) Identify the picture.
b) Label the parts A, B and C.
c) Write the function of D.
Answer:
a) Neuron

b) A – Dendrite
B – Cell body
C – Axon

C) Synaptic knob contains synaptic vesicles. Neurotransmitter in the synaptic vesicles helps to transmit impulse from one neuron to another across synaptic cleft.

Question 18.
This condition can be avoided by administering anti Rh anitbodies to the mother immediately after the delivery of the first child.
a) Identify this condition.
b) Write the reason for this condition.
c) Write the symptoms of the foetus born in this condition.
Answer:
a) Erythroblastosis foetalis

b) During the delivery of the first child, there is a possibility of exposure of the maternal blood (Rh- ve) to small amounts of the Rh + ve blood from the foetus. In such cases, the mother starts preparing antibodies (Rh antibodies ) against Rh antigen in her blood. In case of her subsequent pregnancies, the Rh antibodies from the mother (Rh-ve) can leak into the blood of the foetus (Rh + ve) and destroy the foetal RBCs . Hence anti-Rh antibodies are given to the mother immediately after the delivery of the first child.

c) It cause severe anaemia and jaundice to the baby.

Question 19.
“Metagenesis” is the charcteristic Phenomeon of this phylum.
a) Identify the phylum.
b) Write any four other characteristics of this phylum.
c) Give one example of this phylum.
Answer:
a) Phylum cnidaria or Coelenterates

b) 1) Cnidoblasts present in tentacles and the body are used for anchorage, defense and for the capture of prey
2) They exhibit two basic body forms called polyp and medusa
3) They have a central gastró-vascular cavity with a single opening, hypostome
4) They ar aquatic, marine and radially symmetrical animals

C) Physalia

Question 20.
Match the following :

A	B
a) Tendon	i) Store fat
b) Columnar epithelium	ii) Fluid connective tissue
c) Bone	iii) Attach muscle to bone
d) Adipose Tissue	iv) Helps in secretion
e) Ligament	v) Support
f) Blood	vi) Attach bond to bone
	vii) Secrete hormones
	viii) Conduct impulses

Answer:

A	B
a) Tendon	iii) Attach muscle to bone
b) Columnar epithelium	iv) Helps in secretion
c) Bone	v) Support
d) Adipose tissue	i) Store fat
e) Ligament	vi) Attach bone to bone
f) Blood	ii) Fluid connective tissue

Teachers recommend solving Kerala Syllabus Plus One Zoology Previous Year Question Papers and Answers Pdf Board Model Paper 2021 to improve time management during exams.

Kerala Plus One Zoology Board Model Paper 2021 with Answers

I. Answer any 3 questions from 1 to 6. Each carries 1 score. (3 × 1 = 3)

Question 1.
Name the tissue which is specialized to store fat.
Answer:
Adipose tissue

Question 2.
Select the odd one out. [Lectins, Alkaloids, Amino acid, Drugs]
Answer:
Amino acids

Question 3.
Which blood group is known as ‘Universal recipients’?
Answer:
AB group

Question 4.
Expand the following terms:
(a) TV
(b) RV
Answer:
(a) Tidal volume
(b) Residual Volume

Question 5.
Which one is NOT associated with the structure of eye?
[Cornea, Choroid, Cochlea, Iris]
Answer:
Cochlea

Question 6.
Observe the relationship between the first two terms and fill in the blanks:
(a) Acoelomate Phylum Platyhelminthes
Pseudocoelomate : _______

(b) Cinidoblast : Phylum Cnidaria
Radula : _______
Answer:
(a) Phylum Aschelminthes
(b) Phylum Mollusc

II. Answer any 9 questions from 7 to 24. Each carries 2 scores. (9 × 2 = 18)

Question 7.
Distinguish between diphyodont and thecodont dentition.
Answer:
Diphvodont dentition : Organisms have two sets of teeth during their life,as temporary teeth replaced by a set of permanent teeth. This type of dentition is called diphyodont.

Thecodont dentition : Here tooth is embedded in a socket of jawbone,this type of attachment is,called thecodont.

Question 8.
Match the following:

A	B
Reptilia	Alligator
Mammalia	Pteroptus
Aves	Corvus
Amphibia	Salamandra

Answer:

A	B
Reptilia	Salamandra
Mammalia	Alligator
Aves	Pteroptus
Amphibia	Corvus

Question 9.
Differentiate between Chondrichthyes and Osteich- thyes with an example for each.
Answer:

Class – Chondrichthyes	Class – Osteichthyes
They have cartilaginous endoskeleton	They have bony Endoskeleton
Gill slits are separate and without operculum	They have four pairs of , gills which are covered ’ by an operculum on each side
The skin with minute placoid scales	Skin is covered with cycloid/ctenoid scales
Air bladder is absent	Air bladder is present

Examples chondrichthyes; Scoliodon Examples Osteichthyes; Catla

Question 10.
The peculiar features of different phyla are given below:
(a) Presence of ostia, Osculum and Choanocytes.
(b) Presence of ciliated comb plates and exhibits biluminescence.
(c) Body shows metameric segmentation and nephredium is the excretory organ.
(d) Body with chitinous exoskeleton and Joined appendages.
Identify the Phyla (a), (b), (c) and (d)
Answer:
(a) Phylum – Poriferac
(b) Phylum – Ctenophora
(c) Phylum – Annelida
(d) Phylum – Arthropoda

Question 11.
ECG is a graphical representation of the electrical activity of the heart during a cardiac cycle.
(a) Expand the term ECG.
(b) What does the P-wave represent?
Answer:
(a) Electrocardiogram

(b) P wave represents the electrical excitation (depolarisation) of the atria.

Question 12.
A number of bones related with our appendicular skeletal system is given below. Arrange them into two groups with appropriate headings.
[Humerus, Tibia, Tarsals, Ulna, Radis, Fibula, Carpals, Femur]
Answer:

Bones in forelimb	Bones in Hindlimb
Humerus	Femur
Radius	Tibia
Ulna	Fibula
Carpals	Tarsals

Question 13.
In the given flow chart, label the missing parts:

Answer:
(a) Loose connective tissue
(b) Skin
(c) Bone/cartilage
(d) Bone/Cartilage

Question 14.
Enlist any four types of synovial joints.
Answer:
Synovial joints
(a) Ball and socket joint
(b) Hinge joint
(c) Pivot joint
(d) saddle joint

Question 15.
Distinguish between Uricotelic and Ureotelic animals with one example each.
Answer:

Ureotelic	Uricotel
The organism that excrete urea is called ureotelic	The organism that excrete uric acid is called uricotelic
Eg:Mammals	Eg: Birds and Insects

Question 16.
Complete the given table:

Endocrine gland	Hormone	Function
Pineal gland	(a)	Regulation of 24 hour diurnal rhythm
(b)	Prolactin	Growth of mammary gland and formation of milk
Pancreas	(c)	Increase blood glucose level
Heart	(d)	Dilation of blood vessel and reduces blood pressure

Answer:
(a) Melatonin
(b) Pituitary gland
(c) Glucagon
(d) ANF orAtrial natri uretic factor

Question 17.
Observe the diagram given below

enterjcus on molecules given below complete each reaction with suitable terms.
(a) Identify the class in which it belongs.
(b) Write a note on its migration.
Answer:
(a) Class: Cyclostomata

(b) Cyclostomes are marine but migrate for spawning to fresh water. After spawning, within a few days, they die.Their larvae after metamorphosis, return to the ocean.

Question 18.
The description of low taxonomic aids are given below:
(a) Taxonomic aid based on the contrasting characters generally in a pair called couplet.
(b) A storehouse of collected plant specimens that are dried, pressed and preserved on sheets. Name the taxonomic aids (a) and (b)
Answer:
(a) Key
(b) Herbarium

Question 19.
The different parts of alimentary canal of cockroach is listèd below. Arrange the in a sequential order of food passing through them.
(Crop, Colon, Qesophagus, Gizzard, Ifleum, Rectum)
Answer:
Oesophagus → Crop → Gizzard → Ileum → Colon → Rectum.

Question 20.
The action of different enzymes present in succas enterjcus on molecules given below complete each reaction with suitable terms.

Answer:
(a) Dipetidase
(b) Glucose
(c) Lactase
(d) Fructose

Question 21.
Kidneys are the main excretory organ in human body:
(a) Name the structural and functional unit of kidney.
(b) List out 3 main processes of urine formation.
Answer:
(a) Nephron

(b) i) Glomerular Filtration
ii) Tubular Reabsorption
iii) Tubular Secretion

Question 22.
In a classroom discussion a student said that “Proteins are homopolymer”.
(a) Do you agree with this statement ?
(b) Name the most abundant protein exists in the animal world.
Answer:
(a) No
(b) Collagen

Question 23.
Arrange the following words in a sequential order according to transmission of sound wave.
[Eardrum, Basilar membrane, Ear ossicles, Oval window]
Answer:
Eardrum → Ear ossicles → Oval window → Basilar membrane

Question 24.
An endocrine gland which has a major role in the development of immune system and is degenerate in aged individuals.
(a) Identify the endocrine gland.
(b) Name the hormone which secreted from it.
Answer:
(a) Thymus gland
(b) Thymosin

III. Answer any 3 questions from 25 to 30. Each carries 3 scores. (3 × 3 = 9)

Question 25.
Observe the graph and write answer for the following questions :

(a) Name of the graph.
(b) What are the four factors that affect binding of oxygen with Haemoglobin.
Answer:
(a) Oxygen dissociation curve
(b) pO₂, pCO₂temperature and H⁺

Question 26.
(a) In the following chart A, B, C and D represents:

(b) Name the tract of nerve fibres which help to connect the two cerebral hemispheres.
Answer:
(a) A – Forebrain
B – Hypothalamus
C – Corpora quadrigemina
D – Cerebellum

(b) Corpus callosum

Question 27.
(a) Identify the class enzyme which does the following type of chemical reaction.
S-reduced + S’-oxidised → S-oxidised + S’- reduced.
(b) Write any three factors whjch affect enzyme activity.
Answer:
(a) Oxidoreductase /Dehydrogenase
(b) Temperature, pH and Concentration of substrate,

Question 28.
Alimentary canal of cockroach is given.

(a) Label the parts identified as A, B, C and D
(b) Write the function of ‘C’.
Answer:
(a) A-Crop
B – Gizzard
C – Hepatic caecae
D – Malpighian tubule

(b) It secrete digestive juice

Question 29.
Fill in the blanks to complete the Schematic repre-sentation.

Answer:
(a) Gnathostomata
(b) Cyclostoamata
(c) Osteichthyes
(d) Tetrapoda
(e) Reptilia
(f) Mammals

Question 30.
Match the terms in Column A with those in Column B and C:

A	B	C
BlOOd group	Antigens on RBCs	Antibodies in Plasma
A	A, B	Anti-A, B
AB	Nil	Anti-B
O	A	Ni

Answer:

A	B	C
Blood group	Antigens RBCs	Antibodies in plasma
A	A	Anti- B
AB	A,B	Nil
O	Nil	Anti – A, B

Teachers recommend solving Kerala Syllabus Plus One Zoology Previous Year Question Papers and Answers Pdf Board Model Paper 2022 to improve time management during exams.

Kerala Plus One Zoology Board Model Paper 2022 with Answers

I. Answer any three questions from 1 to 4. Each carries 1 score. (3 × 1 = 3)

Question 1.
In man, the first part of the small intestine is ‘C’ shaped and is called
Answer:
Duodenum

Question 2.
Hypersecretion ofGH : Gigantism ::
Hyposecretion of GH : _______
Answer:
Dwarfism

Question 3.
In a polysaccharide the individual mono-saccharide
are linked by _______
Answer:
Glycosidic bond

Peptide bond, disulphide bond, Glycosidic bond, diester bond

Question 4.
Carbon dioxide is carried by haemoglobin as
Answer:
Carbamino haemoglobin

II. Answer any nine questions from 5 to 17. Each carries 2 scores. (9 × 2 = 18)

Question 5.
a) Differentiate between heterodont dentition and thecodont dentition, b) Write down dental formula of man.
Answer:
a) fleterodont: Different types of teeth present in
ThecodonUlentition : Each tooth is embedded in a socket of jaw bone.
b) Dental formula of man

Question 6.
Observe the figure.

a) Name the parts labelled as A, B, C and D.
Answer:
A – Nerve cord
B – Notochord
C – Gill slits
D – Post anal tail

Question 7.
Complete the flow chart

Answer:
A – Central Nervous system
B – Autonomous Neural system
C – Mid Brain
D – Parasympathetic nervous system

Question 8.
Vassopressin is also called antidiuretic hormone. Justify.
Answer:
It helps in the reabsorption of water & electrolyte from the DCT of kidney and reduces diuresis (loss of water through urine).

Question 9.
Observe the figure.

a) Identify the tissues A, B and C.
b) Name the tissue in which intercalated disc is present.
Answer:
a) A. Skeletal Muscle
B. Smooth Muscle
C. Cardiac Muscle
b) Cardiac Muscle

Question 10.
Taxonomic aids and their explanations given in two columns, Match them correctly.
Answer:

Taxonomic aids	Explanation
Key	Have collection of preserved plant and animal specimens for study and reference.
Museum	Contain information on any one taxon
Zoological park	Taxonomic aid used for identification of plants and animals based on the similarities and dissimilarities.
Monograph	The places where wild animals are kept in protected environments under human care.

Answer:

Taxonomic aids	Explanation
Key	Taxonomic aid used for identification of plants and animals based on the similarities and difference.
Museum	Have a collection of preserved plant and animal specimen s for study and reference
Zoological park	The places where wild animals are kept in protected environments under human care.
Monograph	Contain information on any one taxon

Question 11.
Observe the figure

a) Identify the diagrammatic representation.
b) What does the QRS complex indicates?
Answer:
a) Electro Cardio Gram – ECG
b) QRS – indicates electrical depolarization of ventricles

Question 12.
Fill in the blanks using appropriate words given below.
Ommatidium, Respiration,
Answer:

A _____	Mosaic vision
Spiracle	B _____
Malpighian tubules	C _____
D _____	Grinding food particles

Answer:

A- Ommatidium	Mosaic vision
Spiracles	B-Respiration
Malpighian tubules	C-Excretory organ
D-Gizzard	Grinding food particles

Question 13.
Observe the figure

b) Write the function of organ of corti.
Answer:
a) A-Scala vestibule
B – Tectorial membrane
C – Scala intermedia
b) transduction of auditory signals or Recepter organ for hearing

Question 14.
List out the following as oviparous and viviparous
Corvus, Testudo, Canis, Felis
Answer:
Oviparous-Corvus and Testudo Viviparous – Canis and Felis

Question 15.
Compare the following
a) Adipose tissue and areolar tissue
b) Tendons and ligarfents
Answer:
(a)

Adipose Tissue	Areolar tissue
Seen beneath the skin	Seen beneath the skin
Stores fat	Support frame work for epithelial tissue, contain fibroblast, Macrophage and mast cells

(b)

Tendon	Ligament
Helps to connect muscles to the bone	Helps in bone to bone connection

Question 16.
With the help of an example, explain meta-genesis.
Answer:
Metagenesis is referred to the phenomenon of alternation of generation shown by cnidarians which exhibit both forms- polyps and medusae . Polyps produce medusae asexually and medusae form the polyps sexually e.g., Obelia.

Question 17.
Oxygen dissociation curve is given below.

Answer:
a) Oxyhaemoglobin forms in Lungs alveoli.
b)PO₂ becOmes low
PCO₂ becomes high

Answer any three questions from 18 to 22. Each carries 3 scoers. (3 × 3 = 9)

Question 18.
Observe the diagram

a) Identify the diagram.
b) Label the parts marked as A and B
c) What is glomerulus?
Answer:
a) Malpighian body
b) A-Afferent arteriole
B – Bowman’s capsule
c) Glomerulus -It is an tuft of capillaries formed by afferent arteriole found inside Bowman’s capsule.

Question 19.
a) Name three major categories of joints.
b) What do you mean by a joint?
c) Give an example for Ball and socket joint.
Answer:
a) Fibrous joints, Cartilaginous joints and Synovial joints
b) Joint – it is the point where two or more bones intersect each other.
c) Joint between pectoral girdle and humerus.

Question 20.
Observe the diagrams A and B

a) Name the symmetry exhibits by animals given in A and B.
b) Differentiate the symmetry of A with symmetry of B.
c) Write an example for animal showing asymmetry. U
Answer:
a) A-Radial symmetry
B- Bilateral symmetry

b) Radial symmetry: Body can be divided into 2 similar halves by any plane along central axis of body.
Bilateral symmetry: Body can be divided into 2 right and left halves through a single plane along the longitudinal axis.

c) Phylum Porifera -eg spongilla

Question 21.
a) Mention any three types of co-factors associated with enzyme.
b) Name the co-enzyme present in vitamin niacine.
c) What happens when co-factor is removed from an enzyme?
Answer:
a) Prosthetic group, Co-enzyme and Metal ions
b) NADP contain niacin
c) If a cofactor is removed from an enzyme it cant function as a catalyst.

Question 22.
Schematic plan of blood circulation of man is given below.

a) Name two circulatory pathways.
b) Explain its significance.
c) Comment on hepatic portal system.
Answer:
a) Pulmonary circulation and Systemic circulation.

b) Pulmonary circulation helps in the Oxygenation of blood and removal of CO₂ from blood occurs. Systemic circulation helps to provide nutrients, O₂ and other substances to the tissues and removes CO₂ and other harmful substances.

c) Hepatic portal system: The hepatic portal system is the venous system that returns blood from the digestive tract and spleen to the liver.

Reviewing Kerala Syllabus Plus One Chemistry Previous Year Question Papers and Answers Pdf Model 2022 helps in understanding answer patterns.

Kerala Plus One Chemistry Board Model Paper 2022

Answer any 8 questions from 1 to 11. Each carries 2 scores: (8 × 2 = 16)

Question 1.
Write any two properties of cathode rays. (1)
Answer:

• They contain materjal particle.
• They move in straight line.

Question 2.
i) Mention the principle which restricts the number of electrons in an orbital as two. (1)
Answer:
Pauli’s Exclusion principle

ii) Define orbital (1)
Answer:
Orbitals are the region where the probability of finding an electron is maximum.

Question 3.
Explain sp³ hybridisation. Give an example of a molecule in which the central atom is in sp³ hybridisation.
Answer:
One s-orbital and three p-orbital hybridises to form four sp3 hybrid orbitals of same shape and energy, eg: CH₄, NH₃, H₂O.

Question 4.
Explain the structure of H₂O molecule on the basis of VSEPR theory.
Answer:
In H₂O, sp³ hybridisation occurs and the geometry is tetrahedral with bond angle 109°. 281 but due to the presence of two lone pair of electrons repulsion occurs and bond angle is reduced to 104.5°. Shape changes to bent shape. .

Question 5.
i) Define oxidation and reduction in terms of oxidation number.
Answer:
Oxidation – increase in oxidation number
Reduction – decrease in oxidation number.

ii) Identify the oxidising and reducing agent in the following redox reaction.
Zn + Cu²⁺ → Zn²⁺ + Cu (1)

Reducing agent – Zn- undergoes oxidation Oxidising agent -Cu²⁺ undergoes reduction.

Question 6.
i) Which one of the following is an electron precise covalent hydride? (1)
(a) CH₄
(b) B₂H₆
(c) H₂O
(d) NH₃
Answer:
(a) CH₄

ii) What is Calgon? (1)
Answer:
Sodium hexa metaphosphate – calgon

Question 7.
Match the following:

Answer:

Question 8.
Discuss the structure and bonding in diborane (B₂H₆) molecule.
Answer:


Four terminal B-H bond – 2 centered -2 electron bond. Two B-H-B-3 centred 2 electron bond or bridge bond.

Question 9.
i) Write the IUPAC name of

Answer:
3-chloropropanal

ii) Draw the structure of pent-3-en-2-ol. (1)
Answer:

Question 10.
i) Arrange the following carbocations in the increasing order of their stability. (1)

Answer:

ii) Name the factors which influence the stability of carbocations. (1)
Answer:
Inductive effect, hyper conjugation

Question 11.
Mention any two applications of green chemistry in day to day life.
Answer:
1. biodegradable polymers
2. for bleaching purpose H₂O₂ is used.

Answer any 8 questions from 12 to 23. Each carries 3 scores: (8×3 = 24)

Question 12.
A compound contains 4.07% hydrogen, 24.27% carbon and 71.65% chlorine. Its molar mass is 98.96 g. What are its empirical and molecular formulas?
Answer:

Empirical formula CH₂Cl
Empirical formula mass = 12 + 2 + 35.5 = 49. 5
Molecular mass = 98.96
n = \(\frac{\text { Molecular mass }}{\text { Empirical formula mass }}\) = \(\frac{98.96}{49.5}\) = 2
Molecular formula = Empirical formula × n
= (CH₂Cl₂)₂
MF = C₂H₄Cl₂

Question 13.
i) Distinguish molarity and molality of solution. (2)
Answer
Molarity (M) is defined as the number of moles of solute in one litre’of the solution.
M = \(\frac{W_B}{M_B}\) × \(\frac{1000}{V in ml}\)

W_B → weight of. solute
M_B → Molecular mass of solute
V → Volume of solution

Molality (m): Molality is defined as the no. of moles of solute in one kilogram of the solvent.
m = \(\frac{W_B}{M_B}\) × \(\frac{1000}{W_A in g}\)
W_B → Weight of solute
M_B → Molecular-mass of solute
W_A → Weight pf solvent in gram.

ii) Among molarity and molality which one is tem-perature dependent? (1)
Answer:
Molarity is temperature dependent.

Question 14.
i) What are representative elements? (1)
Answer:
Representative elements: s block elements and p block elements together known as representa¬tive elements.

ii) What are isoelectronic species? Give suitable examples. (2)
Answer:
Isoelectronic species: Species which contains same number of electrons.
N^3-, O^2-, F^–, Na⁺, Mg²⁺, Al³⁺ – All contains 10 electrons.

Question 15.
i) Define electron gain enthalpy. (1)
Answer:
It is the enthalpy change when an electron is 20 added to an isolated gaseous atom

ii) Chlorine has more negative electron-gain enthalpy than flourine. Explain. (2)
Answer:
In flourine new electron is added to 2p orbital, the repulsion is more. In chlorine the new electron is added to 3p orbital due to large size of 3p orbital repulsion is less.

Question 16.
Write the postulates of kinetic molecular theory of gases.
Answer:
The important postulates of Kinetic molecular theory are:

• All gases contains small, minute, large no.of particles called mblecules.
• Molecules are in random motion.
• During their motion they collide with each other and also with the walls of the container. This creat pressure.
• The volume of the gas molecules is negligible as compared to the total volume of the gas.
• There is no force of attraction between the gas molecules.
• Average kinetic energy of the molecules is directly proportional to its absolute temperature.

Question 17.
i) A vessel of 120 ml capacity contains a certain amount of gas at 35°C and 1.2 bar pressure. The gas is transferred to another vessel of volume 180 ml at 35°C. What would be its pressure? (2)
Answer:
\(\frac{P_1 V_1}{T_1}\) = \(\frac{P_2 V_2}{T_2}\) , \(\frac{1.2 \times 120}{308}\) = \(\frac{P_2 \times 180}{308}\)
P₂ = \(\frac{1.2 \times 120}{180}\) = 0.8 bar

ii) What is the effect of temperature on viscosity of liquids? (1)
Answer:
Viscosity decreases with increase in temperature.

Question 18.
i) An example for intensive property is
(a) Mass
(b) Volume
(c) Density
(d) Heat capacity
Answer:
(c) Density

ii) Calculate standard enthalpy of formation (AH°_r) of CO from the following data using Hess’s law. (2)

Answer:

Question 19.
Account for the following:
i) AlCl₃ can act as Lewis acid. (1)
Answer:
AlCl₃ is an electron deficient compound ie. it behaves as Lewis acid.

ii) pH of NH₄Cl in water is less than 7. (1)
Answer:
NH₄Cl + H₂O → NH₄OH + HCl
ie. NH₄CI is a salt of weak base and strong acid hence the pH is less than 7 indicating acidic nature.

iii) Addition of acetate ions to acetic acid decreases the concentration of hydrogen ions [H⁺] (1)
Answer:
Due to common ion effect.

Question 20.
i) Name the different types of redox reactions. (2)
Answer:
i) Disproportionation reaction, Combination reaction Displacement reaction, Decomposition reaction.

ii) Write the chemical reaction takes place when Zn rod is dipped in dil HCl. (1)
Answer:
Zn_(s) + HCl → ZnCl₂ + H₂

Question 21.
i) What is temporary hardness? (1)
Answer:
i) Temporary hardness can be removed easily.

ii) Suggest two methods for the removal of temporary hardness. (2)
Answer:
a) Boiling: On boiling bicarbonates of calcium and magnesium are precipitated as carbonates and is filtered off.
b) Clarks process: By adding lime water (Ca(OH)₂) corresponding carbonates are precipitated and is filtered off.

Question 22.
i) Write the major and minor products formed in the following reaction:
CH₃ – CH = CH₂ + H – Br → (2)
Answer:

ii) Write the rule which governs the formation of major product. (1)
Answer:
Markonikovs rule

Question 23.
Define the following terms:
i) Green house effect. (1)
Answer:
Due to the lack of plants and trees, the CO₂ level of earth’s atmosphere increases and it keeps the ultraviolet radiations in the earths atmosphere. So the temperature increases and ice bergs melts.

ii) Biological Oxygen Demand(BOD) (1)
Answer:
Biological Oxygen Demand (BOD): It is the amount of oxygen needed to degrade organic matter.

iii) Eutrophication. (1)
Answer:
Eutrophication: Due to the presence of phosphates and nitrates the algae and unwanted plants grow easily and it absorbs the dissolved oxyg6n in the water. It affects the aquatic life. This is known as eutrophication.

Answer any 5 questions from 24 to 31. Each carries 4 scores: (5 × 4 = 20)

Question 24.
i) Discuss the postulates of Bohr model of hydrogen atom. (3)
Answer:

• The electrons in an atom are revolving around the nucleus in circular path called orbits.
• As the electrons remain in a particular orbit, it does not lose or gain energy.
• Energy is emitted or absorbed by an atom only when an electron in it moves from the orbital to higher or lower levels.
  ∆E = E₂ – E₁ = hv
• Only those orbits are permitted in which the angular momentum of the electron is a whole no. multiple of \(\frac{h}{2π}\).

ii) Using s, p, d, f notations describe the orbital with the following quantum
a) n = 2, l = 1 (1A)
b) n = 3, l = 2 (1A)
Answer:
a) 2p
b) 3d

Question 25.
i) Represent the MO configuration of N₂ molecule. (2)
Answer:
M.O configuration of N₂ is:

ii) Differentiate intermolecular and intramolecular hydrogen bonding using suitable example. (2)
Answer:
Intermolecular H-bonding: If the hydrogen bond is between the two molecules it is called inter-molecular-H-bonding.
eg: H₂O, HF

Intramolecular H-bonding: If the hydorgen bond is within the molecule. It is called inttramolecular -H-bonding.
eg. Ortho-nitrophenol.

Question 26.
i) State the first law of thermodynamics and write its mathematical expression. (2)
Answer:
“Energy can neither be created nor be destroyed” ’Au=q+w

ii) Define Gibb’s energy. (1)
Answer:
Gibbs free energy: The amount of energy which can be converted to useful work.

iii) Give the relationship between the Gibbs energy change (∆G) and entropy change (∆S) of a reaction.
Answer:
∆G = ∆H – T∆S

Question 27.
i) State Le-Chatelier’s principle. (1)
Answer:
If a system in equilibrium is subjected to change in concentration temperature or pressure the equillibrium shifts in the direction that tends to reduce the effect of the change.

ii) Di hydrogen gas is obtained from natural gas by partial oxidation with steam as per following endothermic reaction.
CH_4(g) + H₂O_(g) → CO_(g) + 3H_2(g)
Write an expression for K_p for the above reaction (1)
Answer:

iii) Describe the effect ofthe following in the equilibrium
CH_4(g) + H₂O_(g) → CO_(g) + 3H_2(g)
a) Increasing the pressure. (1)
b) Increasing the temperature. (1)
Answer:
In forward reaction the number of moles increases.
(a) So increasing pressure favours backward reaction
(b) forward reaction is endothermic so it favours high temperature

Question 28.
i) Describe the solvay process for the manufacture of sodium carbonate. (Na₂CO₃.10H₂O). (2)
Answer:
Solvay process: By passing C02 through
ammonical brine solution sodiumbicarbonate is obtained. It is filtered and heated to get sodium carbonate.

ii) Beryllium shows anomalous properties. Given reason. (2)
Answer:
Small size, high ionisation energy and absence of vacant d orbitals.

Question 29.
i) What is borax bead test? (2)
Answer:
When borax is heated with transition metals beads with characteristic colours are obtained.

ii) CCl₄ cannot be hydrolysed by water. Why?
Answer:
In CCl₄ there is absence of vacant d orbitals.

iiii) CO₂ is a gas but SiO₂ is a solid. Explain. (1)
Answer:
In CO₂ the force between the each molecule is weak vander walls force and the hybridisation is sp which gives linear shape. So it is gas.
In SiO₂ the hybridisation is sp² each Si atom is tetrahedrally connected to oxygen atom.So it has three dimenstional network. So SiO₂ is solid.

Question 30.
i) Name a method used for the estimation of nitro-gen in an organic compound.
Answer:
Kjeldahl’s Method or Dumas Method

ii) How will you detect the presence of chlorine in an organic compound?
Answer:
To the sodium fusion extract add one or two drops of nitric acid and add 1 ml of AgNO₃ solution curdy white precipitate is obtained. This indicates presence of chlorine.

iii) Suggest a method used for the separation of chlo¬roform and aniline. (1)
Answer:
Distillation.

Question 31.
i) Discuss the Huckel rule for aromaticity. (2)
Answer:
For a compound to be aromatic
It should be cyclic, conjugated, planar and should contain (4n +2) no. of pi electrons in the ring.

ii) Draw the Sawhorse projection formula for the eclipsed and staggered conformations of ethane. (2)
Answer:

Teachers recommend solving Kerala Syllabus Plus One Zoology Previous Year Question Papers and Answers Pdf Board Model Paper 2023 to improve time management during exams.

Kerala Plus One Zoology Board Model Paper 2023 with Answers

I. Answer any 3 questions from 1-5. Each carries 1 score.

Question 1.
Which among the following is secreted by pineal gland?
(a) Prolactin
(b) Melatonin
(c) Gastrin
(d) Secretin
Answer:
Melatonin

Question 2.
_______ is a difficulty in breathing causing wheezing due to inflammation of bronchi and bronchioles.
Answer:
Asthma

Question 3.
Name the most abundant protein in the animal world.
Answer:
Collagen

Question 4.
Man : Homo sapiens;
Housefly: _________
Answer:
Musca domestica

Question 5.
Inflammation of glomeruli of kidney is
Answer:
Glomerulonephritis

II. Answer any 9 questions from 6-16. Each carries 2 scores. (9 × 2 = 18)

Question 6.
Name the following:
(a) Plasma without clotting factor.
(b) Blood group known as ‘Universal recepients’.
(c) Protective double walled membranous bag covering human heart.
(d) Pacemaker of human heart
Answer:
(a) Serum
(b) AB group
(c) Pericardium
(d) Sino-atrial node I SAN

Question 7.
Diagram of an ivertebrate organism is given below:

(a) Identify the organism.
(b) Name the phylum to which it belongs.
(c) Write any two characteristics of the phylum
Answer:
a) Pleurobrachia

(b) Ctenophora

(c)
1. Comb plates present
2. Bioluminescence present

Question 8.
Observe the graph given below regarding the concept of activation energy.

(a) What is ‘A’ and ‘B’?
(b) Mention the role of enzyme in the progress of biochemical reaction.
Answer:
(a) A – Activation energy without enzyme.
B – Activation energy with enzyme.

(b) Enzymes bring down the activation energy making the transition of substrate to product more easily.

Question 9.
Expand the folllowing:
(a) ACTH
(b) FSH
(c) TSH
(d) ADH
Answer:
(a) ACTH – Adrenocorticotrophic hormone.
(b) FSH – Follicle stimulating hormone.
(c) TSH – Thyroid stimulating hormone.
(d) ADH – Anti-diuretic hormone.

Question 10.
Figure showing fundamental characteristics of phylum chordata is given below. Name the parts labelled A, B, C and D

Answer:
A-Nerve cord
B – Notochord
C – Post anal tail
D – Gill slits

Question 11.
Distinguish between: enjdralrala^’Pjrojca.
(a) IRV and ERV
(b) TV and RV
Answer:
(a) IRV – Additional volume of air, a person can inspire by a forcible inspiration.
ERV – Additional volume of air, a person can expire by a forcible expiration.

(b) TV (Tidal Volume) -Volume of air inspired or expired during a normal respiration.
RV (Residual Volume) – Volume of air remaining in the lungs even after a forcible Expiration.

Question 12.
Arrange the following animals under suitable headings in the table given below base on their mode of nitrogenous waste excretion.
Bony fishes, Birds, Terrestrial, Amphibians, Mammals

Ammonotelic	Ureotelic	Uricotelic

Answer:

Ammonotelic	Ureotelic	Uricotelic
Bony fishes	Birds	• Terrestrial amphibians • Mammals

Question 13.
Match Column ‘A’ with ‘B’

A	B
Proboscis	Pila
Malpighian tubules	Balanoglossus
Radula	Sycon
Choanocytes	Silkworm

Answer:

A	B
Proboscis	Balanoglossus
Malpighian tubules	Silkworm
Radula	Pila
Choanocytes	Sycon

Question 14.
Details regarding the disorders of human muscular and skeletal system is given below. Name the disorder.
(a) Inflammation of joints due to accumulation of uric acid crystals.
(b) Inflammation of joints.
(c) Rapid spasms in muscle due to low Ca⁺⁺ in body , fluids.
(d) Age related disorder characterised by decreased bone mass and increased chance of fractures.
Answer:
(a) Gout
(b) Arthritis
(c) Tetany
(d) Osteoporosis

Question 15.
Complete the flow that showing the parts of human brain.

Answer:
A – Hindbrain
B – Corpora quadrigemina
C – Thalamus
D – Cerebellum

Question 16.
Molecular structure of some organic compounds found in living tissues are given below. Identify and write its name.

Answer:
(a) Glucose
(b) Alanine
(c) Fatty acid / Palmitic acid
(d) Glycerol.

III. Answer any 3 questions from 17 to 20. Each carries 3 scoers. (3 × 3 = 9)

Question 17.
Diagrammatic presentation of a standard ECG is given below:

(a) Expand ECG.
(b) What does QRS complex wave denotes?
(c) Mention the clinical significance of ECG.
Answer:
(a) Electrocardiogram
(b) QRS – complex -Depolarization of Ventricle
(c) Any deviation in ECG indicates the abnormality of heart.

Question 18.
Based on the characteristics given below, identify and write the phylum with one example for each.
(i) Presence of cnidoblasts or enidocytes on the tentacles and the body.
(ii) Body consists of a distinct head, muscular foot and visceral hump.
(iii) Presence of jointed appendages.
(iv) Presence of flame cells.
Answer:
(i) Coelentrata
eg :- Hydra

(ii) Mollusca eg Pila

(iii) Arthropoda eg Honey bee

(iv) Platyhelminthes eg Ascaris

Question 19.
(a) Give reason for the following:
(i) Pituitary dwarfism
(ii) Diabetes mellitus
(iii) Acromegaly
(iv) Diabetes insipidus
(b) Name the hormones known as “Emergency Hor-mones’ and the gland secreting it.
Answer:
(a)

1. 1. Hyposecretion of Growth Hormone
   2. Prolonged hyperglycemia due to low level of insulin.
   3. Excess secretion of growth hormone in adults.
   4. Less secretion of ADH.

(b)

1. Adrenaline and noradrenaline.
2. Adrenal gland

Question 20.
(a) Structure of a neuron is given below. Label the , parts marked A, B, C and D

Answer:
(a)
A – Nucleus
B – Schwann cells C – Axon
D – Synaptic knob

(b)

1. Unipolar – cell body with one axon only.
2. Bipolar – with one axon and one dendrite.
3. Multipolar -with one axon and two or more dendrites.

Teachers recommend solving Kerala Syllabus Plus One Zoology Previous Year Question Papers and Answers Pdf March 2019 to improve time management during exams.

Kerala Plus One Zoology Previous Year Question Paper March 2019

Answer all questions from question numbers 1 to 3. Each carry 1 score. (3 × 1 = 3)

Question 1.
Binomial nomenclature was proposed by
Answer:
Carolus Linneaus

Question 2.
Tendons and Ligaments are example of…… tissue
a) Areolar
b) Adipose
c) Dense regular
d) Dense irregular
Answer:
Dense regular

Question 3.
______ is the most abundant protein in the animal world.
Answer:
Collagen

Answer any nine questions from 4 to 14. Each carries two score. (9 × 2 = 18)

Question 4.
“All vertebrates are chordates but all chordates are not vertebrates”. Do you agree with this statement? Substantiate.
Answer:
Yes
The notochord is replaced by a cartilaginous or bony vertebral column in the adult.

Question 5.
Distinguish between:
a) Identify the organism
b) Name the calss in which it belongs
Answer:
a) Residual Volume (RV): Volume of air remaining in the lungs even after a forcible expiration. This averages 1100 mL to 1200 mL.
Tidal Volume (TV): Volume of air inspired or expired during a normal respiration. It isapprox. 500 mL

b) Vital Capacity (VC): The maximum volume of air a person can breathe in after a forced expiration.
Total Lung Capacity: Total volume of air accommodated in the lungs at the end of a forced inspiration.

Question 6.
Observe the figure of the organism given below

a) Identify the organism
b) Name the calas In which it belongs
c) Mention any two salient features fo the class
Answer:
a) Hippocampus
b) Osteichthyes
c) 1. They have four pairs of gills which are covered by an operculum on each side.
2. Air bladder is present which regulates buoyancy

Question 7.
a) Name the following:
i) The carbohydrate splitting enzyme preent in human saliva.
ii) The anti bacterial enzyme present in human saliva
Answer:
a) 1. Salivary amylase
2. Lysosyme

b) 1. Intestine
2. Stomach

b) In which region of the alimentary canal does the following reactions occur?

Question 8.
a) Person with ‘AB’ blood group is called ‘universal recepient’. Give a reason.
b) List out any two disorders of human criculatory system.
Answer:
a) Persons with ‘AB’ group can accept blood from persons with AB as well as the other groups of blood. Therefore, such persons are called ‘universal recipients’.

b) 1. High Blood Pressure (Hypertension): Hypertension is the term for blood pressure that is higher than normal (120/80).
2. Coronary Artery Disease (CAD): Coronary Artery Disease, often referred to as atherosclerosis, affects the vessels that supply blood to the heart muscle.

Question 9.
Complete the flowchart given below.

Answer:
a) Gnathostomata
b) Cyclostomata
C) Tetrapoda
d) Osteichthyes

Question 10.
a) Give one word for the following:
i) Presence of Glucose in Urine
ii) Presence of Ketone bodies in Urine
Answer:
a) 1.Glycosuria
2. Ketonuria
b) Diabetes mellitus

b) Which human disorder is having the above mentioned two symptoms?

Question 11.
Observe the figures given below.

a) Identify figure ‘A’ and ‘B’.
b) Name the subunits of ‘A’ and ‘B’
Answer:
a) 1. Actin
2. Myosin

b)

1. Each actin,(thin) filament is made of two ‘F’ (filamentous) actins helically wound to each other. Each ‘F’ actin is a polymer of monomeric ‘G’ (Globular) actins.
2. Myosin consists of monomeric proteins called Meromyosins.
3. Each meromyosin has two important parts, a globular head with a short arm and a tail, the former being called the heavy merotnyosin (HMM) and the latter, the light meromyosin (LMM).

Question 12.
Note the relationship in the first pair and then complete the second pail
a) Insulin : Hypglycemic hormone :
_______ : Hyperglycemic hormone

b) Over secretion of Growth hormone : Gigantism
Low secretion of Growth hormone : _______
Answer:
a) glucagon
b) dwarfism

Question 13.
Observe the diagram A and B given below.

a) What is ‘A’ and ‘B’?
b) Mention the other two levels of protein structure.
Answer:
a) A- Secondary structure of protein
B- tertiary structure of proteins

b) primary structure of proteins and quarternary structure of proteins

Question 14.
Classify the following animals on the basis of the mode of nitrogenous waste excretion in the table given below.
Mammals, Birds, Bony fishes, Reptiles,
Terrestrial amphibians, Aquatic amphibians

Ammanotehc	Ureotehc	Uricotelic

Answer:

Amonotelic	Ureotelic	Urecotehc
Bony fishes	mammals	repti
Aquatic amphibians	Terrestrial amphibians	Birds

Answer any three questions from 15 to 18. Each carries three scores. (3 × 3 = 9)

Question 15.
Find the odd one from each group. Justify your answer.
a) Starfish, Devilfish, Dogfish, Jellyfish
b) Flying fish, Angel fish, Saw fish, Fighting fish
c) Sea lily, Sea cucumber, Sea hare, Sea urchin
Answer:
a) Dog fish-belongs to chordates while others are nonchordates
b) Saw fish-belongs to chodricthyes while others are osteichthyes
c) Sea hare-belongs to phylum mollusca while others are phylum Echinodermata

Question 16.
Prepare a flow chart showing the parts to human brain, by using the details given below.
Cerebrum, Medulla, Mid brain, Thalamus, Pons,
Corpora quadrigemina, Hypothalamus, Forebrain,
Cerebellu, Hypothalamus, Hind brain, Brain.
Answer:

Question 17.
Diagrammatic representation of a standard ECG is given below.

a) Exapnd ECG
b) What dows the ‘P’, T waves denote?
c) Mention the clinical significance of ECG.
Answer:
a) ECG – electrocardiogram

b) P wave – atrial depolarization
T wave- ventricular repolarisation

c) It helps in the diagnosis of heart diseases

Question 18.
Match column ‘A’ with those in columns ‘B’ and ‘C’.

A	B	C
Type of simple Epithelum	Location	Function
Squamous Epithelum	(a)    ________	Diffusion
(b)   ________	Ducts of glands and tubular parts of nephrons in kidneys	(c)    ________
Columnar Epithelium	(d)  ________	Secretion and Absorption
(d)   ________	Inner suface of bronchioles and fallopian tubes	(e)   ________

Answer:
a) found in the wall of blood vessels
b) cuboidal epithelium
c) secretion /absorption
d) lining of stomach or intestine
e) ciliated epithehum
f) movement/transport

Teachers recommend solving Kerala Syllabus Plus One Zoology Previous Year Question Papers and Answers Pdf March 2020 to improve time management during exams.

Kerala Plus One Zoology Previous Year Question Paper March 2020

Answer any 3 questions from 1 to 5. Each carries 1 score. (3 × 1 = 3)

Question 1.
Select the enzyme that facilitate the following reaction:

a) Succinic dehydrogenase
b) RuBiScO
b) Carbonic anhydrase
d) Lipase
Answer:
b) Carbonic anhydrase

Question 2.
Which among the following is a primary metabolite?
Answer:
Amino acids

Question 3.
Name the portion of the myofibril between two successive Z-Hne.
a) H-zone
b) Sarcomere
c) l-band
d) M-line
Answer:
b) Sarcomere

Question 4.
Identify the word pair applicable to phylum ctenophora.
a) Nephridia, Parapodia
b) Comb plates, Bioluminescence
c) Polyp, Metagenesis
c) Radula, Visceral hump
Answer:
b) Comb plates, Bioluminescence

Question 5.
Unit of classification is ______.
a) Taxon
b) Species
c) Genus
d) Cell
Answer:
a) Taxon

II. Answer any 9 questions from 6 to 16. Each carries 2 scores. (9 × 2 = 18)

Question 6.
Cells of human body perform different types of . movement.
Write any two types of movement and the parts that exhibit the movement.
Answer:
Amoeboid movement – It is shown by macrophages and leucocytes in blood
Muscular movement – It is shown by limbs, jaws and tongue

Question 7.
Find out the suitable term from the box for the disorders stated.
a) Accumulation of Urea in blood.
b) Insoluble mass of crystallised salts in the kidney.
c) Surgical method for the correction of Renal failures.
d) inflammation of golmeruli of kidney.
Answer:
a) Uremia
b) RenaI Calculi
c) Kidney Transplantation
d) Glomerulonephntis

Question 8.
Characteristics of certain animals are given. Arrange them under the ‘Class’ to which these animals belong.
i) Skin is moist without scales.
ii) Body is covered by dry and corn ified skin.
iii) Shed the scales as skin cast.
iv) Can live in aquatic as well as terrestrial habitats.
Answer:

Class Amphibia	Class Reptilia
Skin is moist without scales	Body is covered by dry and cornified skin
Can Hve in aquatic as well as terrestrial habitats	Shed the scales as skin cast

Question 9.
When substrate concentration increases, the velocity of enzymatic reaction increases at first. After attaining a mzximum velocity, it cannot be exceeded by further addition of substrates. Why?
Answer:
Enzyme molecules are fewer than substrate molecules. After saturation of substrate molecules; there are no free enzyme molecules to bind with additional substrate molecules.

Question 10.
“The products of digestion like glucose and amino acids are absorbed to the blood by active transport, where as electrolytes like chloride ions are generally absorbed by simple’diffusion.”
How will you differentative active transport from simple diffusion?
Answer:

1. In active transport, passage of substance into the blood takesplace against the concentration gradient by using energy.
2. In simple diffusion, substances are moved from higher concentration to lower concentration without using energy.

Question 11.
Distinguish between the following terms :
a) IRV, ERV
b) Tidal volume, Residual volume
Answer:
a) Expiratory Reserve Volume (ERV): Additional volume of air, a person can expire by a forcible expiration.
Inspiratory Reserve Volume (IRV): Additional volume of air, a person can inspire by a forcible inspiration.

b) Residual Volume (RV): Volume of air remaining in the lungs even after a forcible expiration
Tidal Volume (TV): Volume of air inspired or expired during a normal respiration

Question 12.
Enzymes present in Saliva, gastric juice and intestinal juice are given in the box.
a) Identify the enzyme present in gastric juice and intestinal juice one each.
b) Write their digestive function :
Pepsin, Lysozyme, Trypsinogen, Rennin, Lipases Salivary amylase
Answer:
a) Gastric juice : Pepsin, Rennin Intestinal juice: Lipase

b) Pepsin – Proteolytic enzyme
Rennin – Proteolytic enzyme of infants Lipase – Lipolytic enzyme

Question 13.
Complete the flow chart showing the regulation of kidney functioning by Juxta Glomerukar Apparatus and Adrenal Cortex.

Answer:
A) Renin
B) Angiotensin-l
C) Aldosterone
D) Increase in blood pressure and GFR

Question 14.
‘Adrenal medulla is the centrally located tissue in the adrenal gland, where as adrenal cortex is located outside.’
How do adrenal and medulla differ in their function?
Answer:

Adrenal Cortex	Adrenal Medulla
They secrete Glucocorticoids, Mineralo? corticoids & Sex corticoids	They secrete Epinephrine and nor epinephrine (Catecholamine)
Gluco corticoids involved in carbohydrate metabolism	It is produced during emergency situations. Hence called emergency hormone

Question 15.
‘Cockroach is said to be Uricotelic.
a) What do you understand about the nature of excretion of Cockroach from this statement?
b) Name two excretory organs of Cockroach.
Answer:
a) Cockroach excrete uric acid
b) Malpighian tubule and Nephrocytes

Question 16.
Rewrite the given sentences if there is any mistake in the underlined part.
• Cartilage cells are called osteocvcles.
• Bones are rich in Calcium salts.
• Intercalated discs are seen in skeletal muscle.
• Skeletal muscles are striated.
Answer:
Cartilage cells are called Chondrocytes
Intercalated discs are seen in Cardiac muscle

III. Answer any 3 questions from 17 to 20. Each carries 3 scores.

Question 17.
Observe the diagram

a) What does it denote?
b) What do P, QRS, T represent?
c) What is its clinical significance?
Answer:
a) ECG
b) P-Wave: Electrical Excitation (Depolarisation) of atria
QRS-Wave-Depolarisation of ventricle T-Wave- Return of the ventricle from excited to normal state (Replarisation)

c) ECG: It gives electrical activity of heart during a cardiac cycle, ECGs obtained from different individuals have the same shape any deviation from this shape indicates abnormality or disease

Question 18.
Complete the given table appropariately?

Gland	Hormones	Function
i) (A) ___	Androgens	Development of male accessory sex organs
ii) Thymus	(B) ___	(C) ___
iii) (D) ___	Glucogen	Maintains normal blood glucose levels
iv) Pineal	(E) ___	(F) ___

Answer:
A – Testis
B – Thymosin
C – Provide CMI and Humoral immunity or differentiation of Tlymphocyes
D – Pancreas
E – Melatonin
F – Regulate 24 hour rhythm of our body

Question 19.
Observe the figures.

a) Identify the organisms A, B & C.
b) Name the phylum to which each of them belong,
Answer:
A – Balanoglossus – Phylum Hemichordata
B – Nereis-Phylum Annelida
C – Liver Fluke-Phylum Platy helminthes (Flat worms)

Question 20.
Observe the diagram.

a) Name the parts A & B.
b) Write the characteristics features of ‘C’.
c) Arrange the given parts of eye in the sequence that light travels from the external environment into the eye. (Vitreous, chamber, lens, retina, Aqueous chamber)
Answer:
a) A-lens B-Optic nerve

b) Fovea- yellowish pigmented spot on retina .Here the. cones are densely packed. It is the point where the visual acuity (resolution) is the greatest

c) Cornea → aqueous chamber → lens → vitreous chamber → Retina