1) Which of the following statements is wrong?
a)Pollen grains remain viable for several months because their outer covering is made
of sporopollenin
b)No enzyme can degrade sporopollenin
c)Pollen grains are well represented in fossil strata due to sporopollenin
d)Pollen wall has cavities containing proteins
2)“In Western countries a large number of …… Product in the form of tablets and
……. are available in market. Pollen consumption claimed to increase the …… of
athelete”. The words to fill blanks in sequential order are
a)Pistil, syrup, power b)Stamen, food, sexual urge
c)Carpel, yoghurt, libido d)Pollen, syrup, performance
3) Self incompatibility is
a)For encouraging self-fertilisation pollination
b)Genetic method for preventing self-pollination
c)Both (a) and (d)
d)Found in unisexual flower
4) Which hormone level reaches peak during luteal phase of menstrual cycle?
a) Luteinizing harmone c) Progesterone
b) Follicle stimulating harmone d) Oestrogen
5) Follicular phase is also called
a) Secretory phase b) Luteal phase c) Proliferative phase d) Menstrual phase
6) What is the purpose of polar bodies during oogenesis?
a) Polar bodies serves both as a dumping ground for extra sets of chromosomes and ensure
that the ovum will have most of the cytoplasm
b) They rid the body of defective sets of chromosomes, leaving the ‘good’ set within the
ovum
c) They are merely the by-product of meiosis and serve no function
d) They prevent the development of most sets of multiple birth
7)Embryo at 8 to 16 cell stage is called
a) Blastula b) Morula c) Trophoblast d) All of these
DELHI PUBLIC SCHOOL, RUBY PARK, KOLKATA
Holiday Homework
Class 12
I) Very Short Answer type Questions (MCQs) [1m each]
8) Which of the following floral parts forms the pericarp after fertilisation?
(a) Nucellus (b) Outer integument
(c) Ovary wall (d) Inner integument
9) The outermost layer of a blastocyst is called
(a) ectoderm (b) mesoderm (c) endoderm (d) trophoblast
10) In a fertilised embryo sac, the haploid, diploid and triploid structures are:
(a) Synergid, zygote and primary endosperm nucleus.
(b) Synergid, antipodal and polar nuclei.
(c) Antipodal, synergid and primary endosperm nucleus.
(d) Synergid, polar nuclei and zygote.
II) Short Answer type Questions I [2m each]
1. How does pollination occur in sea grasses?
2. Why are some seeds of Citrus referred to as polyembryonic? Explain how they are
formed.
3. List the different parts of the human oviduct through which the ovum travels till it meets
the sperm for fertilization.
4. Where are the fimbriae present in the human reproductive system? Give their function.
5. Name the blank spaces a, b, c and d from the table given below:
6. Where is sporopollenin present in plants? State its significance with reference to its
chemical nature
III) Short Answer type Questions II [3m each]
1. Name and explain three contrivances of cross pollination.
2. Discuss the different methods of endosperm formation in angiosperms
3. Spermatogenesis in human males is a hormone-regulated process. Justify.
4. Name the pituitary hormones influencing the Leydig cells and the Sertoli cells present in
the human testes. Explain the functions of these cells.
IV) Long Answer type Questions [2m each]
1. Explain the development of the secondary oocyte(ovum) in a human female from the
embryonic stage upto ovulation. Name the hormones involved in this process.
2. How does embryo development occur in dicots? Describe its parts.
V) Read the following passage and answer the questions that follows:
1) As the ovules transform into seeds, the ovary develops into a fruit after fertilisation in
angiosperms; these two processes occur simultaneously. The fruits may be fleshy fruits or dry
fruits. The fruits may be true fruits or false fruits while some others may be parthenocarpic
fruits. Seedless fruits can be induced to develop by the application of auxins and gibberellins.
(a) Give an example of (i) a fleshy fruit and (ii) a dry fruit.
(b) What does the ovary wall develop into, in a fruit? Name its different regions/parts that
can be distinguished in a fleshy fruit.
(c) What is common among strawberry, apple and cashew, with respect to their fruits?
(d) What technical term is given to the development of ovary into a fruit without
fertilisation? Give an example.
2) The reproductive cycle in the females of primate mammals (apes, monkeys and humans),
is called menstrual cycle. Menstrual cycles occur during the reproductive phase, i.e., between
menarche and menopause in human females. The cycle starts with menstruation and extends
(for about 28 days) till the onset of the next menstruation; it includes four phases.
(a) Name in proper sequence, the four phases in menstrual cycle.
(b) How long does the menstrual phase last in a menstrual cycle?
(c) When do the hormones estrogen and progesterone reach their peak levels,
respectively, in the menstrual cycle? Give reasons.
(d) Define ovulation.
