Question

a) What are fossils and how is age of fossils determined?

b) During artificial selection, which features of wild cabbage were selected to give rise to i) Cabbage ii) Cauliflower

Answer 1

Fossils are the dead impressions of pre-existing organisms. We can determine the age of Fossils by observing which fossil is above and which is more deep. The fossil which is near to the ground is more recent than the one which is deep .
b. During artificial selection
I) cabbage= less distance between the leaves characteristics was selected.
ii) cauliflower= the sterile flower characteristics was selected.

Answer 2

1. body or its parts that are not decomposed/ preserved traces of organisms.

2. upon digging the earth, the fossils that are found closer to the surface are more recent than the fossils in deeper layers.

3. by selecting the ratios of different isotopes of the same element in the fossil material.

b. 1: by selecting very short distance b/w leaves.

2: by selecting sterile flowers.