Kerala Plus Two Botany Board Model Paper 2022 with Answers

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

Kerala Plus Two Botany Board Model Paper Model 2022 with Answers

Part – I

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

Question 1.
Observe the relationship of the first pair and fill in the blank.
Restriction enzyme: Cutting of DNA
_______ : Joining of DNA fragments.
Answer:
DNA Ligase

Question 2.
Choose the correct answer and fill up the blank. The single cotyledon of monocotyledons are called
(plumule, radicle, scutellum, coleorrhiza)
Answer:
Scutellum

Question 3.
Name the association between fungi and roots of higher plants.
Answer:
Mycorrhiza

Question 4.
Which among the following equation is related with net primary productivity?
(a) GPP + R = NPP
(b) NPP-R = GPP
(c) GPP + NPP = R
(d) GPP-R = NPP
Answer:
GPP – R = NPP

B. Answer all questions from 5 to 6. Each carries 1 score. (2 × 1 = 2)

Question 5.
Fill in the blank.
Animals that have their DNA altered and express a foreign gene are known as ____.
Answer:
Transgenic animals

Question 6.
Choose the correct answer.
The protective, outer thick wall of the fruits in angiosperms. (Perisperm, Endosperm, pericarp, Integument)
Answer:
Pericarp

Part – II

Answer any two questions from 7 to 9. Each carries 2 scores. (2 × 2 = 4)

Question 7.
Observe the given diagram showing the process of maturation of insulin.

(a) Explain the structure of Proinsulin.
(b) What are the change that occur in Proinsulin when it becomes mature insulin?
Answer:
(a) Proinsulin composed of polypeptide chains A and B are connected with an extra stretch-called the C peptide.
(b) C peptide is removed during maturation.

Question 8.
Match the following:

Asexual Reproductive Structures	Organisms
(a) Zoospores	Hydra
(b) Buds	Penicillium
(c) Conidia	Sponges
(d) Gemmules	Chlamydomonas

Answer:

Asexual Reproductive Structures	Organisms
(a) Zoospores	Chlamydomonas
(b) Buds	Hydra
(c) Conidia	Penicillium
(d) Gemmules	Sponges

Question 9.
MOET is an advanced animal breeding technique for herd improvement. Expand MOET. Which hormone is used for superovulation?
Answer:
Multiple Ovulation Embryo Transfer Technology. FSH (Follicle stimulating hormone)

B. Answer any two questions from 10 to 13. Each carries 2 scores. (2 × 2 = 4)

Question 10.
Distinguish euryhaline and stenohaline organisms.
Answer:
Euryhaline organisms :- They can tolerate wide range of salinity.
Stenohaline organisms :- They can tolerate narrow range of salinity.

Question 11.
In many plants more than one embryo is seen in one seed. Name the phenomenon with an example,
Answer:
Polyembryony : Example Seeds of orange or citrus

Question 12.
Write any two points that are important for successful poultry farm management.
Answer:

• Selection of good breeds
• Provide proper food & water

Question 13.
Given below are the different stages of hydrarch succession. Forest, marshmeadow, phytoplankton, Reed swamp, submerged free floating stage, scrub, submerged plant stage. Write down the pioneer species and climax community. Arrange the stages in correct sequential order.
Answer:
Pioneer species – Phytoplankton.
Climax community – Forest.
Phytoplankton → Submerged plant stage → Submerged freefloating plant stage → Reed → swamp → Marsh- Meadow → Scrub → Forest stage.

Part – III

Answer any three questions from 14to 17. Each carries 2 scores. (3 × 3 = 9)

Question 14.
The equation of population density is given below.N_t+1 = N_t + [(BB + I) – (D + E)]
(a) What does D and E stand for?
(b) Write two factors which increase the population density.
Answer:
(a) D – Mortality
E – Emigration

(b) Natality & Immigration

Question 15.
Increase in the level of green house gases lead to overheating of earths atmosphere.
(a) Name the phenomenon.
(b) State any two consequences of this phenomenon.
Answer:
(a) Global warming
(b) Affects weather & climate ( El Nino effect), Melting of polar ice caps & Himalayan snow caps that leads to rise in sea level.

Question 16.
Observe the given ecological pyramid in an aquatic ecosystem.

Identify the type of pyramid and reason out why the pyramid is inverted.
Answer:
Pyramid of biomass Here biomass of primary producers (phytoplanktons) is much less than primary consumers (zooplanktons)

Question 17.
Bt-cotton is an example of genetically engineered plant. Name the gene responsible for Bt-toxin production. Explain how Bt-toxin kill the insect.
Answer:
Cry gene
When an insect ingest the inactive insecticidal protein crystals, it is converted into an active toxin due to the alkaline pH of the gut which solubilise the crystals. The activated toxin binds to the surface of midgut epithelial cells and create pores that cause cell swelling and lysis and eventually leads to death of the insect.

B. Answer the following question. Carries 3 scores. (1 × 3 = 3)

Question 18.
Vehicular emission is the major cause of air pollution.
(a) Write four steps taken by Delhi Government for reducing vehicular pollution.
(b) What is CNG?
Answer:
(a)

1. Use of low-sulphur petrol & diesel,
2. Use of catalytic converter
3. Use of CNG & Use of unleaded petrol etc.

(b) Compressed Natural Gas

Part – IV

Answer any one question from 19 to 20. Carries 5 scores. (1 × 5 = 5)

Question 19.
The given diagram depicts the separation of DNA fragments.

(a) Identify the technique.
(b) How can you visualize the separated DNA fragments in this technique?
(c) What is elution?
Answer:
(a) Gel electrophoresis
(b) Separated DNA fragments can be visualised after staining with Ethidium bromide followed by exposure to UV light.
(c) Separated bands of DNA are cut out from the agarose gel and extracted from gel piece.

Question 20.
Given below is the diagram of a mature embryosac in angiosperm.

Label the parts a,b, c and d.
What is double fertilization? Mention the ploidy of zygote and PEN.
Answer:
a – Synergids
b – Secondary nucleus or Polar nuclei
c – Antipodals
d – Filiform apparatus

Two types of fusion like syngamy and triple fusion are together known as Double fertilization Zygote – Diploid (2n), PEN – Triploid (3n)