Question

1. The forelimbs of early mammals were similar in all features except FUNCTION. Can you tell me why the answer is function and why not the other choices?

a.     embryonic origin

b.     position on the body

c.     number

d.     function

e.     composition

2. Why are swamps, tar pits, seafloor and caves habitats favoring fossil preservation. Why is desert not?

3. Population is not used in describing species. How is Interbreeding, sexual reproduction, natural selection and color are used in describing species?

Answer 1

1. All the mammals has sexual reproduction in which the sperm fuses with the ovum to form embryo. Option a is incorrect.

From the name itselt, it is clear that the forelimbs are positioned in the front side of the body. Option b is incorrect.

Number of forelimbs do not change in mammals. All the mammals have 2 forelimbs. Option c is incorrect.

Some marine mammals have forlimbs that are transformed into paddles. In animals such as horse, the forelimbs are for running and walkling. For mammals such as human, the forlimbs are for grasping. So the function varies. Option d is correct.

All the forlimbs have same bone composition. The difference in size and proportion of the bones corresponds to the difference in the forelimbsamong the mammals. Option e is incorrect.