1. In which type of parthenogenesis are only males produced?
d) Both a and b
Answer: a. Arrhenotoky
2. Animals giving birth to young ones:
d) Both a and b
Answer: c. Viviparous
3. The mode of reproduction in bacteria is by
a) Formation of gametes
b) Endospore formation
d) Zoospore formation
4. In which mode of reproduction variations are seen
d) Both a and b
Answer: c. Sexual
5. Assertion and reasoning questions:
In each of the following questions there are two statements. One is assertion (A) and other is reasoning (R). Mark the correct answer as
A. If both A and R are true and R is correct explanation for A
B If both A and R are true but R is not the correct explanation for A
C. If A is true but R is false
D. If both A and R are false.
I. Assertion: In bee society, all the members are diploid except drones.
Reason: Drones are produced by parthenogenesis.
A B C D Answer: A
II. Assertion: Offsprings produced by asexual reproduction are genetically identical to the parent.
Reason: Asexual reproduction involves only mitosis and no meiosis.
A B C D Answer: A
III. Assertion: Viviparous animals give better protection to their offsprings.
Reason: They lay their eggs in the safe places of the environment.
A B C D Answer: C
6. Name an organism where cell division is itself a mode of reproduction.
Amoeba reproduces by fission, that is by cell division
itself a mode of reproduction.
7. Name the phenomenon where the female gamete directly develops into a new organism with an avian example.
The phenomenon is Parthenogenesis. Turkey is the bird
in which the female gamete directly develops into a new organism.
8. What is parthenogenesis? Give two examples from animals
• The egg develops into a complete individual without fertilization is known as parthenogenesis.
• Example : Rotifers,
Honeybees and Turkey
9. Which type of reproduction is effective -Asexual or sexual and why?
• Sexual reproduction is more effective than asexual reproduction.
• In asexual reproduction there is no variation.
• In sexual reproduction due to fusion of two gametes, variation is found.
10. The unicellular organisms which reproduce by binary fission are considered immortal. Justify.
• Amoeba is an unicellular organism, which is considered as immortal.
• The parental amoeba mitotically divides into two daughter amoebae.
11. Why is the offspring formed by asexual reproduction referred as a clone?
• The offsprings formed by asexual reproduction is genetically identical to the parent.
• They can also be referred as a clone.
• Clone is the exact copy of an organism which it is developed.
12. Why are the offsprings of oviparous animal at a greater risk as compared to offsprings of viviparous organisms?
• The offsprings of the viviparous organism develops within the female.
• The offsprings of the oviparous organisms develops in the external environment.
• There are certain external environment factors that affects the development of the offsprings.
• Hence offsprings of the oviparous animals are at greater risk.
13. Give reasons for the following:
(a) Some organisms like honey bees are called parthenogenetic animals
(b) A male honey bee has 16 chromosomes where as its female has 32 chromosomes.
a) Organisms like honey bees can reproduce without fertilization.
b) • Male honey bees are formed without fertilization (ie) Egg alone.
• Female honey bees are formed fertilization (ie) Fusion of male and female gamete.
• That is why male has 16 chromosomes in the egg
• The female are diploid having 32 chromosomes, 16 from male and 16 from female.
14. Differentiate between the following:
(a) Binary fission in amoeba and multiple fission in Plasmodium
Binary fission in amoeba
• It is a simple binary fission type.
• Contractile vacuole disappears.
• Nucleoli disintegrate
Multiple fission in plasmodium
• In plasmodium multiple fission occurs in the schizont and in the oocyte stage.
• Multiple fission in schizont stage is called schizogony and it is called merozoites.
• Multiple fission in oocyte is called sporogony and the individual is called sporozoites.
(b) Budding in yeast and budding in Hydra
Budding in yeast
• It is an asymmetrical division.
• It produces a bud like projection.
• The bud grows and enlarges.
• The nucleus also splits and enters the bud.
Budding in hydra
• It is an exogenous budding.
• Ectodermal cells projects out.
• Along with endoderm they form a bud.
• The gastrovascular cavity of the parent continues in the bud
• The bud separates and develops into hydra.
(c) Regeneration in lizard and Planaria
Regeneration in lizard
• It is epimorphosis type of regeneration.
• It is replacement of the lost part.
• It is restorative regeneration.
Regeneration in planaria
• It is morphallaxis type of regeneration.
• New planaria can develop from a small fragment of it.
• The developed plaparia will be an active individual.
15. How is juvenile phase different from reproductive phase?
• It is the period of growth between the birth of the individual upto reproductive maturity.
• The juvenile stage of certain organisms
Insects - Larva
Cow - Calf
Ape - Infant
Cat - Kitten
Reproductive Phase :
• The period in which the organisms are able to reproduce.
• Each organism's breeding time differs.
• If they reproduce at the particular period of the year it is called seasonal breeders.
• If they are able to reproduce throughout their sexual maturity it is known as continuous breeders. (Eg.) Poultry and Rabbit.
16. What is the difference between syngamy and fertilization?
• It is the fusion of male and female pronuclei after fertilization.
• It confirms the diploid state of the zygote.
• It is the fusion of male and female gamete.
• It refers to the process of confirming fertility.