In animals exhibiting external fertilization:

1. the offspring are less prone to predation
2. the reproduction is independent of water
3. there is synchrony between sexes for the release of gametes
4. the number of female gametes are highly reduced

Subtopic:  Sexual Reproduction |
 83%
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The number of chromosomes in the shoot-tip cells of a maize plant is 20. The number of chromosomes in the microspore mother cells of the same plant shall be:

1. 20

2. 10

3. 40

4. 15

Subtopic:  Sexual Reproduction |
 68%
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Organisms relying completely on external fertilization are almost always likely to be found in:
1. Tropical forests
2. Moist environments
3. Aquatic habitats
4. Dry, arid conditions

Subtopic:  Sexual Reproduction |
 86%
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Match each item in Column I with one item in Column II and chose your answer from the codes given below.

Column I

(plant)

Column II

(vegetatively propagated by)

I. Pistia 1. Stem
II. Asparagus 2. Root
III. Kalanchoe 3. Leaves


Codes:

Options: I II III
1. 1 2 3
2. 2 1 3
3. 2 3 1
4. 1 3 2

Subtopic:  Asexual Reproduction |
 66%

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The process of sexual reproduction which involves meiosis and syngamy is:

1. Apomixis 2. Amphimixis
3. Agamospermy 4. Diplospory

Subtopic:  Sexual Reproduction |
 57%

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The number of chromosomes in a gamete of Ophioglossum is:

1. 1260 2. 380
3. 630 4. 78
Subtopic:  Sexual Reproduction |
 62%
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There is no natural death in single-celled organisms like Amoeba and bacteria because:

1. They cannot reproduce sexually

2. They reproduce by binary fission

3. Parental body is distributed among the offspring

4. They are microscopic

Subtopic:  Asexual Reproduction |
 72%
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Given below are a few statements related to external fertilization. Choose the correct statements.

i. The male and female gametes are formed and released simultaneously.
ii. Only a few gametes are released into the medium.
iii. Water is the medium in a majority of organisms exhibiting external fertilization.
iv. Offspring formed as a result of external fertilization have a better chance of survival than those formed inside an organism.
 
1. iii and iv 2. i and iii
3. ii and iv 4. i and iv
Subtopic:  Sexual Reproduction |
 85%
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Consider the given statements:

I. Gemmules are asexual reproductive structures in sponges.
II. In Bryophyllum, vegetative propagation takes place by leaf buds.
III. Marchantia is monoecious and Chara is dioecious.


The correct statements are:

1. Only I and II 2. Only I and III
3. Only II and III 4. I, II, and III
Subtopic:  Asexual Reproduction | Sexual Reproduction |
 72%
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Grafting is not successful in monocots but is successful in dicots because they have:
1. Vascular bundles arranged in a ring
2. Cambium for secondary growth
3. Vessels with elements arranged end to end
4. Cork cambium

Subtopic:  Sexual Reproduction |
 61%

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