Answer:
rabbits and humans share a common ancestor
Answer:
B) There is an increase in the number of giraffes with long necks in areas of Africa where low-growing trees have died
Explanation:
The directional selection is one of the ways of the natural selection in which the natural selection selects or favours the most extreme trait of the species and the extreme trait show higher fitness than the normal or average trait.
In the given question, the case of Giraffe necks shows directional selection as the normal length of the neck is not favoured by the environment but the extreme trait that is long neck is favoured by the environment and the selection shifted to that level.
Thus, Option-B is the correct answer.
Answer:
A
Explanation:
<em>The correct option would be </em><em>A.</em>
<u>The presence of ammonia in the atmosphere of primitive earth provided the nitrogen found in the amine groups of amino acid and the nitrogenous bases in DNA. This has been proven through the simulation experiment of the primitive earth's atmosphere by Stanley Miller and Harold Urey.</u>
The water in the primitive atmosphere was formed from the condensation of water vapour from volcanoes that were characterics of the earth's environment while oxygen in itself is not needed for photosynthesis but a by-product of it.
Cells that are mainly (alive) and that have more then 1 cell
PROKARYOTES ARE SINGLE CELLED ORGANISMS