TROPOSPHERE is the anwser
Answer:
it is the mechanism of evoluition
Explanation:
evolution is natural because it happens without human interferance from humans and the traits are not desired by humans, but by the plants themselves
D most intense and longest duration is the answer
Explanation:
Pollen grains are the male gametes in plants. It is present on the anthers. Pollen grains finds its way to the ovule by the process of pollination. The structure of pollen grains vary from one species of flower to another. The hibiscus and spider lily both have circular pollen grain.
However, the atomic structure of pollen grain of hibiscus represents the Buckminster fullerene but is not shown in spider lily. The pollen grains of hibiscus have spikes on its surface.