Answer:
a prezygotic barrier
Explanation:
Both wild tigers and lions are said to be reproductively isolated.
Reproductive isolation is defined as the existence of barrier between organisms of different species such that they cannot reproduce.
The mechanisms of reproductive isolation varies. While some act to prevent the formation of zygotes (in case of mating) between organisms of different species, some ensures that the resulting zygotes are invalid.
Reproductive isolation mechanisms that act to prevent fertilization and formation of zygotes are referred to as prezygotic mechanisms while those that ensure that invalid zygotes result (in case of successful fertilization) are referred to post zygotic mechanisms.
<em>The natural differences in the ranges of wild tigers and lions ensure that both animals do not mate with each other, let alone results in zygote. This is a form of pre-zygotic reproductive isolation mechanism.</em>
The sun appears to cross the plane of Earth's equator
when it reaches either one of the "equinox" points in the sky.
There you go! I hope it helped you :)
Answer:
The correct answer is - through facilitated diffusion and active transport.
Explanation:
Glucose is a six-carbon sugar molecule that is directly utilized by cells to provide energy. A glucose molecule is large enough to go through a cell membrane with simple diffusion.
Cells help glucose molecules to cross the cell membrane through facilitated diffusion and active transport. Active transport is of two types primary and secondary active transport to help the glucose molecule to cross the membrane.
Thus, the correct answer is - through facilitated diffusion and active transport.
