Juvenile Phase

Q.

Define Juvenile phase

Q. Choose the incorrect statement.

1. The end of juvenile/vegetative phase marks the beginning of the reproductive phase.
2. In monkeys and apes, the cyclical changes that occur during reproductive phase are called oestrus cycle.
3. Adventitious buds arise from the notches present at margins of leaves of Bryophyllum.
4. Many mammals are reproductively active throughout their reproductive phase and hence are called continuous breeders.

Q. Juvenile phase in plants is also known as

1. vegetative phase
2. reproductive phase
3. post-reproductive phase
4. senescence phase

Q.

Which stage marks the beginning of the reproductive phase?

Q. Complete the missing links:

The period of development before hatching or birth is called _____.

Q. Juvenile phase in plants is also known as

1. vegetative phase
2. reproductive phase
3. post-reproductive phase
4. senescence phase

Q.

The period of growth and maturity in organisms before they can reproduce sexually is known as

1. Juvenile phase

2. Senescence phase

3. Reproductive phase
4. None of the above

Q. Seed habit is an important step in evolution. It is due to

1. Heterogamy
2. Homospory
3. Homogamy
4. Heterospory

Q.

The period of growth and maturity in organisms before they can reproduce sexually is known as

1. Juvenile phase

2. Senescence phase

3. Reproductive phase
4. None of the above

Q. Selaginella and Salvinia are considered the first plants to exhibit a significant step toward evolution of seed habit because

1. Megaspores possess endosperm and embryo surrounded by seed coat.
2. Female sex organs are absent.
3. They are homosporous.
4. Embryo develops in female gametophyte which is retained on parent sporophyte.

Q. Selaginella and Salvinia are considered to represent a significant step toward evolution of seed habit because

1. Female gametophyte is free and gets dispersed like seeds.
2. Female gametophyte lacks archegonia.
3. Megaspores possess endosperm and embryo surrounded by seed coat.
4. Embryo develops in female gametophyte which is retained on parent sporophyte.

Q. Match the follpwing phases of an organism's life cycle to their correct description.

1. Vegetative growth
2. Sexual maturity
3. Deterioration

Q. Assertion :Red algae are most advanced. Reason: They have diplobiontic life cycle.

1. Both Assertion and Reason are correct and Reason is the correct explanation for Assertion
2. Both Assertion and Reason are correct but Reason is not the correct explanation for Assertion
3. Assertion is correct but Reason is incorrect
4. Assertion is incorrect but Reason is correct

Q. When transition from juvenile to adult is gradual then this type of development is called _____________.

1. Homoblastic development
2. Heteroblastic development
3. Homoheteroblastic development
4. Hetero and homoblastic development

Q. Match the follpwing phases of an organism's life cycle to their correct description.

1. Vegetative growth
2. Sexual maturity
3. Deterioration