In animals exhibiting external fertilization:

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

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

Match each item in Column I with one item in Column II and chose your answer from the codes given below.

Codes:

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

The number of chromosomes in a gamete of Ophioglossum is:

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

Given below are a few statements related to external fertilization. Choose the correct statements.

Consider the given statements:

The correct statements are:

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