Xylem is a type of vascular tissue that is responsible for moving water through a plant from its roots to its leaves. Columns of xylem tissue begin in the root hairs and rise all the way up through the leaves of a plant
If later is was 100 million years ago, later b would be 200 million years ago (because it is 100millions years prior to a). And therefore layer c must b 300 million years ago.
<span>taken or considered over a short time period; short-term.</span>
Answer: The correct answer is option a.
Explanation:
Prezygotic isolation is a mechanism by which mating and fertilization is prevented. Thus, it prevents the formation of a zygote.
It can be achieved by various reasons such as temporal differences (difference in mating seasons), habitat isolation, behavioural differences (different mating rituals such as different dance patterns, voice calls, et cetera), mechanical isolation, et cetera.
Thus, different breeding calls prevent the species to interbreed with each which ultimately prevent the formation of zygote formation.
Hence, it is a type of prezygotic isolation.
Answer:
The answer is, D. Aphotic.