Botany · Class 12 Science

Kerala Dhse Class 12 Botany — Real Previous-Year Papers

with complete answers

Real previous-year board papers, year by year — the official exam pattern, the full question paper, and every question solved the concept-first way. Distinct from the chapter-wise textbook bank.

2013–2026
Years of papers: 14
Total Papers: 14
Real Board Papers: 0
Sample papers: 270
Real-paper Q & A: 0
Sample-paper Q & A

Real board-paper questions available, by year

20 Q2026complete

20 Q2025complete

19 Q2024complete

20 Q2023complete

20 Q2022complete

31 Q2021complete

20 Q2020complete

18 Q2019complete

18 Q2018complete

17 Q2017complete

17 Q2016complete

17 Q2015complete

16 Q2014complete

17 Q2013complete

Kerala DHSE Plus Two Board 2026 · Set ANNUAL

Real board examination

About this paper

The real Class-12 board examination held in 2026. Every question below is solved the concept-first way. Sample papers are labelled honestly — never shown as a past exam.

Total marks: 30
Questions: 20
Duration: 120 min
Sections: 3

The marks / questions / duration above are the official exam pattern. We currently have 20 of this paper’s questions (100% of the full paper), with 20 fully solved. Questions we couldn’t yet extract or verify are held — never shown as complete.

Sections & marks

Section	Type	Questions	Marks each	Total
ASection A	choice	5	1	5
BSection B	choice	11	2	22
CSection C	choice	4	3	12
Total		20		30

The question paper

The questions we hold for this paper, laid out by section. Solutions are on the Answers tab.

Board Examination

Botany

Kerala DHSE Plus Two Board 2026 · Set ANNUAL

Series/Set: ANNUALRoll No. ________

Time Allowed: 2 hoursMaximum Marks: 30

General Instructions

This question paper contains 20 questions divided into 3 sections — A, B, C.
Section A comprises 5 questions of 1 mark each (choice).
Section B comprises 11 questions of 2 marks each (choice).
Section C comprises 4 questions of 3 marks each (choice).

Above is the official exam pattern. The questions printed below are those we currently hold for this paper.

Section A

choice · 1 mark each · 5 of 5 shown

Q1.

A genetic mechanism which prevents inbreeding depression in majority of angiospermic plants is ________.

(a) Parthenogenesis
(b) Parthenocarpy
(c) Mutation
(d) Self-Incompatibility

[1]

Q2.

Given below are the steps carried out to construct a recombinant DNA.

(i) Isolation of genetic material
(ii) Insertion of recombinant DNA in the host cell /organism
(iii) Obtaining the foreign gene product
(iv) Amplification of gene of interest
(v) Downstream processing. Which one of the following gives the correct sequences of these steps?
(a)
(i)
(iii)
(iv)
(ii)
(v)
(b)
(i)
(iv)
(ii)
(iii)
(v)
(c)
(ii)
(i)
(iii)
(iv)
(v)
(d)
(ii)
(iv)
(v)
(iii) (i)

[1]

Q3.

Name the Indian crop variety for which in 1997, an American company got patent right through the US Patent and Trademark Office.

[1]

Q4.

The status of human population reflected in the human age pyramid given below is

(a) Declining population
(b) Stable population
(c) Expanding population
(d) Extinct population.

[1]

Q5.

If 10,000 Joules of energy is available at the producer level, how much energy would typically be available to the tertiary consumer?

[1]

Page 1 of 4

Section B

choice · 2 marks each · 11 of 11 shown

Q1.

Some flowers selected for artificial hybridisation do not require emasculation but bagging is essential for them. Give reason.

[2]

Q2.

Name the organic materials from which the exine and intine of an angiosperm pollen grain are made up of. Explain which property of exine that protects pollen grain.

[2]

Q3.

DNA cannot pass through cell membrane of bacteria, why? How is a bacterial cell made competent to take up foreign DNA?

[2]

Q4.

Match the following: Column I | Column II I. DNA Ligase | A. Remove nucleotide from ends of DNA II. Exonucleases | B. Extends Primer on a DNA template III. Taq Polymerase | C. Cut DNA at Specific Position IV. Restriction Endonuclease | D. Joins the DNA fragments

[2]

Q5.

Insulin in the human body is secreted by pancreas as prohormone/proinsulin. The schematic polypeptide structure of proinsulin is given below. The proinsulin needs to undergo processing before it becomes functional in the body. Observe figure and answer the questions that follows. (a) State the changes the Proinsulin undergoes at the time of processing to become functional. (b) How are the two Polypeptide of a functional insulin chemical held together?

[2]

Q6.

Why does the insecticidal protein produced by Bacillus thuringiensis not kill the bacterium, but kills the cotton bollworms? Explain.

[2]

Q7.

State the various defence mechanisms that the following organisms have to evolve to protect themselves from predators: (a) Frogs (b) Monarch butterfly

[2]

Page 2 of 4

Q8.

Study the graph which is given below and answer the questions that follows: (I) Which one of the two curves is considered as more realistic one for most of the animal population? And why? (II) The curve 'b' is described by the following equation: dN/dt = rN (K-N)/K What does 'K' stands for this equation?

[2]

Q9.

Identify the following interactions: (a) Barnacles on whale (b) Mycorrhiza (c) Abingdon tortoise and goats (d) Ticks and dogs

[2]

Q10.

Ecological pyramids give important information about the ecological systems, but do have some limitations. List two limitations of ecological pyramids.

[2]

Q11.

Detritus are the raw materials for decomposition. There are several steps involved in this decomposition process. Name and explain the processes in which earth worm and bacteria carry on detritus.

[2]

Section C

choice · 3 marks each · 4 of 4 shown

Q1.

(a) Identify the figure given below. (b) and also identify the parts B, C, D, E. (c) State the function of 'E'.

[3]

Q2.

(a) Simple stirred-tank bioreactor are used to produce large quantities of recombinant proteins, stirring the contents and mixing it with oxygen. Write any four other features of stirred-tank bioreactor. (b) After downstream processing, the product of biosynthetic stage cannot be marketed directly, why? Give one reason.

[3]

Page 3 of 4

Q3.

(a) What are transgenic animals? (b) Name the transgenic animals those having the largest number amongst all the existing transgenic animals. (c) Mention any three purposes for which these animals are produced.

[3]

Q4.

(a) What is primary productivity of an ecosystem and how is it expressed? (b) State the equation that represents it. (c) Rate of formation of new organic matter by consumer is called ____.

[3]

Page 4 of 4