<span>In cell biology, mitosis is a part of the cell cycle when replicated chromosomes are separated into two new nuclei.</span>
Answer:
a. two plant species flowering at different times.
Explanation:
<em>The only option that is not a post-zygotic reproductive isolation mechanism would be option a, when two plant species flower at different times.</em>
Post-zygotic reproductive isolation mechanisms are those mechanisms that act to ensure that the product of fertilization remains invalid. This is as opposed to pre-zygotic isolation mechanisms that act to prevent fertilization and hence, formation of zygotes.
In option b, c, d and e; the zygote has been formed already and all the forces are just acting to ensure that it remains invalid. whereas in option a, there is no fertilization yet.
<u>Two plant species flowering at different times will ensure that there is no cross pollination between the two species. Without pollination, there cannot be a zygote formation.</u>
Hence, the correct option is a.
The body's first line of defense is the mucous membranes
Nitrogen is a crucially important component for all life. It is an important part of many cells and processes such as amino acids, proteins and even our DNA. It is also needed to make chlorophyll in plants, which is used in photosynthesis to make their food as part of these life processes, nitrogen is transformed from one chemical form to another. The transformations that nitrogen undergoes as it moves between the atmosphere, the land and living things make up the nitrogen cycle.
so i would choose b or c hope this helps
