Kerala Syllabus Class 10 Biology Model Question Paper Set 4

Reviewing solved Biology Question Paper Class 10 Kerala Syllabus Set 4 English Medium helps in understanding answer patterns.

Biology Class 10 Kerala Syllabus Model Question Paper Set 4

Time: 1 ½ Hours
Total Score: 40

Instructions:

1. The first 15 minutes is cool-off time.
2. This time can be used for reading the questions and planning the answers
3. Write answers only according to the instructions and questions
4. While writing the answers, consider the score and time.

Questions from 1 to 4 carry 1 score each. (4 × 1 = 4 scores)

Question 1.
Communicable diseases are diseases caused by mi-croorganisms and transmitted from one person to another.

Which of the following are included in the category of communicable diseases?
1. Dengue fever
2. Chikungunya
3. Typhoid
4. Malaria
5. Diabetes

A. 1,2, and 3 only
B. 1,2, 3, 4, and 5.
C. 1,2, 3, and 4 only
D. 2, 4 only
Answer:
C. 1,2, 3, and 4 only

Question 2.
Find the correctly matched pair from the given answers.

Hypothalamus	Relay station of messages
Thalamus	Centre of memory
Pons	Regulates the rate of ventilation.
Cerebrum	Helps in maintaining homeostasis

(a) A: i, B: ii, C: iii, D: iv
(b) A: iii, B: i, C: iv, D: ii
(c) A: iii, B: iv, C: ii, D: i
(d) A: iv, B: i, C: iii, D: ii
Answer:
(d) A: iv, B: i, C: iii, D: ii

Question 3.
Select and write the correct answer.
Statement 1: Somatic chromosomes are chromo-somes that control physical characteristics.
Statement 2: The SRY gene on the X chromosome is responsible for the development of testis in the embryo.
Statement 3: The Y chromosome is comparatively smaller than that of the X chromosome.
(A) Statements 1, 2 are correct
(B) Statements 1, 3 are correct
(C) Statements 1,2,3 are correct
(D) Statements 2, 3 are correct
Answer:
(B) Statements 1, 3 are correct

Question 4.
Examine the statement and reason and select the correct answer.
Statement: Blood group A has both A and B anti-gens on the surface of red blood cells.
Reason: Blood group A contains only A antigen and anti-B antibodies.
(A) Both the statement and the reason are correct. The reason is the correct explanation of the state¬ment.
(B) Both the statement and the reason are correct. The reason is the wrong explanation of the state¬ment.
(C) Statement is correct. Reason is wrong.
(D) Statement is wrong. Reason is correct.
Answer:
(D) Statement is wrong. Reason is correct.

Questions from 5 to 11 carry 2 scores each. (7 × 2 = 14 scores)

Question 5.
Observe the picture and answer the questions given below.

(a) Identify the genetic processes responsible for variations.
(b) Identify the part indicated as (i), What is its peculiarity?
Answer:
a) Crossing over
b)Chiasma . The chromatids break at this region and the broken segments are exchanged with each other.

Question 6.
A. Prepare a flowchart on how smell is effected.
Answer:
While breathing, the particles responsible for smell enter the nasal cavity. → The particles gets dis-solved in the mucus produced by mucus membrane → Olfactory neurons in the mucus membrane get stimulated by special olfactory particles. → Re-ceptors generate impulses, and they travel through the olfactory nerve to reach the part of the brain recognising smell → The sense of smell is effected.

OR
B. We are unable to recognize smell and taste of food when we have cold. Can you say the reason?
Answer:
Smell influences tasting. During cold, excess mucus will be produced in the nasal cavity. This will obstruct the normal stimulation of olfactory receptors and hence, we are unable to recognize smell and feel the food tasteless.

Question 7.
The symptoms of a disease is given below.
Sudden onset of fever, headache, muscle pain, red-ness of the eye, vomiting
(a) Identity the disease.
(b) How this disease is transmitted?
Answer:
(a) Rat fever (Leptospirosis)
(b) Through wounds or through the mucous mem-branes of the eyes and nose from the water con-taminated with rat urine.

Question 8.
Complete the table related to Biology and Artificial Intelligence.

Personalised medicine	_____(a)_____
_____(b)_____	Analyses large amounts of genetic data and suggests simplification strategies

Answer:
(a) Analyses each individual’s genetic makeup and health information and recommends the most suit-able treatment regimens for them,

(b) Bioinformatics

Question 9.
Observe the illustration and answer the questions given below.

a) Identify the illustration.
b) Complete the illustration.
Answer:
(a) Position of DNA
(b) A – Chromosome B- DNA

Question 10.
A. Appu was taken by fear, on seeing a snake on his way back to school and then ran back.
a) Which part of the autonomous nervous system controls the body activities of Appu in the above situation?
b) What are the changes that takes place in the intestine and eye during the above situation?
Answer:
A.
a) Sympathetic nervous system
b) Peristalsis slows down in the intestine and the pupil in the eye dilates
OR

B. All reflex actions take place under the control of the spinal cord. Evaluate the statement and justify with suitable examples.
Answer:
All reflex actions are not under the control of the spinal cord. Some reflex actions are under the control of the cerebrum. These reflexes are known as cerebral reflexes. E.g., We blink our eyes when light suddenly falls on our eyes.

Question 11.
How these technologies helps in environmental con-servation.
a) Global Biodiversity Data Sensors
b) Bioremediation:
Answer:
a) A technology that collects information about biodiversity using satellite remote sensing, acoustic analysis and camera traps
b) Uses microorganisms and plants to remove pol-lutants from contaminated environments such as soil, water and air. This converts the pollutants into harmless compounds.

Questions from 12 to 17 carry 3 scores each. (6 × 3 = 18 scores)

Question 12.
What are the uses of DNA Fingerprinting
Answer:
To identify culprits, To identify genetic disorders and leam about hereditary diseases, To determine the biological relationship between parents and offsprin, To understand lineage by identifying fossils, To iden-tify victims of accidents or disasters, To track en-dangered species.

Question 13.
A. A plant produces hundreds of seeds. However, only a few among them attain complete maturity. What would be the circumstances that might lead a new plant species to evolve from this plant after millions of years?
Answer:
Overproduction : The plant produces more seeds than the environment can support. Most of them fail to grow due to limited resources.

Variations : Among the seeds that sprout, there are differences in traits like size, immunity, and seed production. Some variations are favourable, while others are not.

Struggle for Existence : Because of limited food, space, and other resources, the seedlings compete with each other for survival.

• Survival of the Fittest – Only those plants with favourable variations, like better adaptability, survive and grow to maturity. They are able to reproduce more effectively.
• Natural Selection – Favourable traits get passed on to the next generation. Over a long period of time, more variations accumulate, and new plants with different traits may emerge. Eventually, this leads to the evolution of a new species.

OR

B. Explain Lamarckism.
Answer:
Giraffes used to have short necks that ate food from the ground. Due to the scarcity of food, giraffes’ necks lengthened as a result of stretching their necks to reach leaves from higher branches. Acquired traits are passed down through generations, resulting in giraffes with longer necks.

Question 14.
A. Processes related to maintaining the equilibrium of the body are given below. Analyse and arrange them in the correct order.
a) Impulses are formed.
b) Muscular movements are coordinated.
c) Maintains the equilibrium of the body.
d) Sensory hair cells of the vestibular apparatus are stimulated.
e) Impulses reach the cerebellum.
f) Body movements create the movement of fluid inside the vestibule and semicircular canal.
Answer:
f) Body movements create the movement of fluid inside the vestibule and semicircular canal.
d) Sensory hair cells of the vestibular apparatus are stimulated.
a) Impulses are formed.
e) Impulses reach the cerebellum.
b) Muscular movements are coordinated.
c) Maintains the equilibrium of the body.

OR
B. Vision is enabled when the impulse from the retina reaches the cerebrum through the optic nerve.
a) Draw a flow chart showing the pathway of light from cornea to retina.
b) There is no vision at the point where the optic nerve starts. Why?
Answer:
a) LighE → Cornea → Aqueous humor → Pupil → Lens → Vitreous humor → Retina

b) Rod cells and cone cells arc absent in the pan from where the optic nerve stans (photo receptors are absent). So there is no vision.

Question 15.
Fill in the blanks in the illustration given below.

Answer:
A) tt
B) t
C) Tt
D) dwarf

Question 16.
Observe the illustration and answer the questions.

a) Which process is indicated in the illustration?
b) Which white blood cells participate in this process?
c) Write the various steps in this process in order.
Answer:
a) Phagocytosis.
b) Monocyte, neutrophil.
c) Phagocytosis – different stages:

1. The phagocyte cell is attracted to the site of infection by chemicals released by the pathogen or by signals from damage to the body.
2. The phagocyte cell uses its cell membrane to engulf the pathogen. This cavity inside the cell where the pathogen has entered is called the phagosome.
3. The phagosome fuses with a lysosome. The resulting cavity is called the phagolysosome. This step is crucial for destroying the pathogen.
4. Inside the phagolysosome, powerful digestive
   enzymes (for example, hydrolytic enzymes) in the lysosome digest the pathogen’s cell wall and proteins.
5. After the pathogen is completely destroyed and digested, the unwanted debris is expelled from the cell.

Question 17.
What are vaccines? .Write the mechanism of the ac-tion of vaccines
Answer:
Vaccines are the substances used to get artificial immunity. Vaccines act as antigens in our body. It stimulates our immune system and helps to produce antibodies against the pathogens. These antibodies remain in the body and provide long-term protection against diseases. By taking the doses accurately vaccines help to gain protection from a disease for many years or even for a lifetime.

The 18th question carries 4 scores (1 × 4 = 4 scores)

Question 18.
A. Complete the table given below.

Hormones	Function
Testosterone	_____(a)_____
Estrogen	_____(b)_____
_____(c)_____	Lactation
_____(d)_____	Reabsorption of water from kidney

Answer:
(a) The activity of male sex organs, Sperm production, cycle. Control of secondary sexual characteristics Controls secondary sexual characteristics
(b) The activity of female sex organs. Production of ovum. Menstrual
(c) Oxytocin (d) ADH/ Vasopressin

B. The following figure shows the relationship of hypothalamus with an endocrine gland.

a) Write down the name of endocrine gland marked as X
b) Write down the name of hormones produced in A and B.
c) Mention the functions of hormones produced in B.
Answer:
a) Pituitary gland
b) A – Tropic hormone
B – Oxytocin and vasopressin
c) Oxytocin helps to contraction of smooth muscles and vasopressin helps in the reabsorption of water in the kidneys.