Notes

A. THE LIFE CYCLE OBJECTIVES

A. Choose the correct alternatives and rewrite the complete sentences
1. The filament of spirogyra undergoes ....................... resulting in numerous
filaments.
(a) budding (b) regeneration (c) fragmentation (d) spore formation
2. ....................... reproduces from the buds on the leaf margin.
(a) Lotus (b) Rose (c) Jasmine (d) Bryophyllum
3. ....................... is the receptive organ on which pollen germinates.
(a) Style (b) Stigma (c) Anther (d) Ovary
4. The elongated part of carpel bearing stigma at its tip is called ..................... .
(a) style (b) stigma (c) anther (d) ovary
5. In plants, male germ cells are produced by ....................... .
(a) filament (b) anther (c) pollen grains (d) stamen
6. ....................... serves as nutritive tissue for the growing embryo.
(a) Embryo sac (b) Endosperm (c) Ovary (d) Fruit
7. The ovule develops into a ....................... .
(a) fruit (b) seed (c) flower (d) ovary
8. The ovary develops into a ....................... .
(a) fruit (b) seed (c) flower (d) ovule
9. Testes secrete the hormone ....................... which brings about changes
in boys during puberty.
(a) progesterone (b) estrogen (c) thyroxine (d) testosterone
10. Immature sperms travel to the ....................... for development and storage.
(a) vas deferens (b) penis (c) testes (d) epididymis
11. ....................... is a passage through which the sperm travels towards the
urethra.
(a) Vas deferens (b) Penis (c) Epididymis (d) Seminal vesicle
12. The ovaries secrete the hormone ....................... which brings about changes
in girls during puberty.
(a) progesterone (b) estrogen (c) thyroxine (d) testosterone
13. Planaria reproduces by ....................... .
(a) fragmentation (b) budding (c) binary fission (d) regeneration


Answers.
1. Fragmentation
2. bryophyllum
3. stigma
4. style
5. pollen grains
6. endosperm
7. seed
8. fruit
9. testosterone
10. epididymis
11. vas deferens
12. estrogen
13. regeneration



B. Fill in the blanks :
*1. The two main methods of reproduction are .. .. .. .. .. .. .. .. .. .. .. . and ....................... .
*2. The functional unit in a plant’s sexual reproduction is ....................... .
*3. The male reproductive part of a flower is ....................... .
*4. When the transfer of pollen from an anther to the stigma occurs in the same flower, the process is called ....................... .
*5. ....................... give rise to variety and diversity.
*6. Hydra uses regenerative cel ls for reproduction in the process of...................... .
*7. Yeast reproduces by ....................... .
*8. During unfavourable conditions, the amoeba secretes a hard covering called
....................... .
*9. A basic process in reproduction is the creation of a ....................... copy.
*10. ....................... is necessary to maintain the number of individuals of a species.
11. In asexual reproduction the cells divide ....................... .
12. The ....................... of bread mould (Mucor) are thread like structures.
13. The mould forms spores inside a ....................... .
14. ....................... is the process by which an entire organism is reproduced
in a genetically identical manner, from a parent organism.
15. ....................... enables organisms to adapt and survive in the changing
environment.
16. Stamen is made up of ....................... and ....................... .
17. If pollen is transferred from one flower to the flower of another plant of the
same species, it is known as ....................... .
18. One male gamete fuses with the egg cell to form ....................... .
19. The second male gamete fuses with the secondary nucleus in the embryo sac to form ....................... .
20. ....................... is a muscular tube that extends from the vaginal opening
to the uterus.
21. ....................... provides the route for the menstrual blood to leave the
body during menstruation.
22. ....................... connect uterus to the ovary.
23. The embryo gets all the nutrients and oxygen from its mother’s blood in
the oviduct supplied through the ....................... .
24. The ....................... has prepared guidelines and considered reproductive
health as a fundamental human right.
25. ....................... was the first mammal to be cloned from an adult cell rather
than an embryo.
26. As soon as the egg cell (zygote) is fertilized, it begins to divide until it
becomes a ball of cells called ....................... .
A. Answers.
1. Asexual reproduction, sexual reproduction
2. Flower
3. Stamen
4. Self pollination
5. Variations
6. Budding
7. Budding
8. Multiple
9. DNA
10. Reproduction
11. Mitotically
12. Hyphae
13. Sporangium
14. Animal cloning
15. Variation
16. Anther, filament
17. Cross pollination
18. Zygote
19. Endosperm
20. Vagina
21. Vagina
22. Oviducts
23. Umbilical cord
24. WHO
25. Dolly sheep

26. Blastocyst