Max.
Marks: 70
Time: 3 Hours
Chapters Covered:
Section – A
(Each question carries 1 mark)
1. Filiform apparatus is a characteristic feature of:
A. Egg cell
B. Synergids
C. Antipodals
D. Embryo
2. Coconut water from a tender coconut represents:
A. Endosperm
B. Nucellus
C. Embryo sac
D. Endocarp
3. Pollination in water hyacinth and water lily is brought about by:
A. Insects or wind
B. Water
C. Birds
D. Bats
4. Seed formation without fertilisation in flowering plants involves:
A. Apomixis
B. Parthenocarpy
C. Syngamy
D. Somatic hybridisation
5. A typical unfertilised angiosperm embryo sac at maturity is:
A. 8-nucleate and 7-celled
B. 7-nucleate and 7-celled
C. 6-nucleate and 6-celled
D. 8-nucleate and 8-celled
6. Number of spermatids produced from 25 primary spermatocytes is:
A. 25
B. 50
C. 75
D. 100
7. The milk produced in the initial few days of lactation is called:
A. Colostrum
B. Lactin
C. Prolactin
D. Albumin
8. What is the function of polar nuclei in angiosperm embryo sac?
A. Fuse with sperm to form endosperm
B. Develop into embryo
C. Fertilise the ovum
D. None of these
9. Haemophilia is rare in females because:
A. It is dominant
B. It is recessive and carried on X chromosome
C. It is Y-linked
D. Females lack X chromosome
10. What is the codon for methionine in mRNA?
A. AUG
B. UAA
C. GUA
D. ACA
11. Which part of DNA gets transcribed into mRNA?
A. Both strands
B. Template strand
C. Coding strand
D. DNA polymerase
12. Which of the following is an example of adaptive radiation?
A. Marsupials in Australia
B. Wings of birds
C. Eyes of octopus and mammals
D. None of these
Assertion–Reason (Q13–16)
A. Both Assertion (A) and Reason (R) are true, and Reason (R) is the correct explanation of
Assertion (A).
B. Both Assertion (A) and Reason (R) are true, but Reason (R) is not the correct explanation of
Assertion (A).
C. Assertion (A) is true, but Reason (R) is false.
D. Assertion (A) is false, but Reason (R) is true.
13.
A: A typical unfertilised angiosperm embryo sac at maturity is 8-nucleate and 7-celled.
R: The egg apparatus has two polar nuclei.
14.
A: Colostrum contains antibodies.
R: It is important for developing immunity in the newborn.
15.
A: Thalassemia is caused due to quantitative defect in globin chain synthesis.
R: It is an autosomal recessive disorder.
16.
A: DNA polymerase can add nucleotides only in 5’→3’ direction.
R: It initiates synthesis of both strands simultaneously from the origin.
Section – B
(Short Answer – 2 Marks Each)
17. Differentiate between menarche and menopause.
18. What are the component cells of the egg apparatus in an embryo sac?
19. Why is sex education necessary in schools? Suggest two ways to improve reproductive
health.
20. Differentiate between monohybrid and dihybrid cross with suitable examples.
21. Define dominance. Differentiate between incomplete dominance and codominance.
Section – C
(Short Answer – 3 Marks Each)
22.
Explain the menstrual cycle events on the following days:
i) Ovarian event from 13–15 days
ii) Ovarian hormone levels from 16–23 days
iii) Uterine events from 24–29 days
23. Write the measures one should take to maintain reproductive health.
24. Explain the inheritance of blood groups in humans using a cross.
OR
The following figure shows a foetus within the uterus. On the basis of the given figure, answer
the questions that follow:
(a) In the above figure, choose and name the correct part (A, B, C or D) that act as a temporary
endocrine gland and substantiate your answer. Why is it also called the functional junction?
(b) Mention the role of B in the development of the embryo.
(c) Name the fluid surrounding the developing embryo. How is it misused for sex-determination?
25. Explain the structure of nucleosome with a labelled diagram.
26. Describe the contributions of Hugo de Vries to the theory of evolution.
27. Differentiate between mRNA, tRNA and rRNA based on structure and function.
OR
Karyotype of a child shows trisomy of chromosome number 21. Identify the disorder and state
the symptoms which are likely to be exhibited in this case.
28. These pictures show the gynoecium of
(A) Papaver and
(B) Michelia.
Write the difference in the structure of their ovaries.
Section – D
(Case-Based – 4 Marks Each)
29.
Given below are certain situations. Analyse the situation and suggest the name of suitable
contraceptive device along with mode of action.
Situation Requirement of contraceptive for Name of Mode of action
contraceptive device
1 blocking the entry of sperms
through cervix
2 spacing between children
3 effective emergency contraceptive
4 terminal method to prevent any
more pregnancy in female
5 sterilization in male
30. Study the Pedigree chart given below and answer the questions that follow:
(a) On the basis of the inheritance pattern exhibited in this pedigree chart, what conclusion can
you draw about the pattern of inheritance?
(b) If the female is homozygous for the affected trait in this pedigree chart, then what
percentage of her sons will be affected ?
(c) Give the genotype of offsprings 1,2,3 and 4 in III generation.
OR (c) In this type of inheritance pattern, out of male and female children which one has less
probability of receiving the trait from the parents. Give a reason.
Section – E
(Long Answer – 5 Marks Each)
31.
State Mendel’s law of independent assortment. Explain it with the help of a dihybrid cross.
32.
Describe Hershey and Chase experiment. What did it prove?
33.
How does industrial melanism support Darwin’s theory of Natural Selection? Explain with an
example.
OR
a) Identify the polarity of x to x’ in the diagram below and mention how many more amino acids
are expected to be added to this polypeptide chain.
B).Mention the codon and anticodon for alanine.
(c) Why are some untranslated sequences of bases seen in mRNA coding for a polypeptide?
Where exactly are they present on mRNA?
