Answer:
Molecules which move against the concentration gradient across the cell membrane employ the mechanism of active transportation.
Explanation:
Normally, permitted molecules moves across the cell membrane of the cell by the process of diffusion and osmosis. This is used when molecules move from hypertonic region to hypotonic region (if ions) and hypotonic to hypertonic (if water). This is a passive transportation which do not require the expense of energy from the cell.
In contrast, when molecules move in or out of the cell against their concentration gradient, that is ions moving from hypotonic region to hypertonic region, they implore the expense of energy in form of adenosine triphosphate (ATP), and the involvement of the membrane carrier proteins. This is called active transport.
Well the endoplasmic reticulum has both smooth and rough bodies. Smooth is the synthesis of fats and detoxifies harmful bodies. Mostly in the liver. And the rough mainly synthesize proteins which are basic components of life. Proteins are sent all over the body and are used for many functions. The golgi is used to package those proteins and send those proteins through the body. Mitochondria creates energy and is the power house of the cell. And the plasma membrane is like the gate keeper. Decides what can enter it exit the cell and prevents harmful things from coming in. Allows proteins to leave.
Answer:
This is an example of "Disruptive selection".
Explanation:
<em>Disruptive selection</em> occurs when <em>selective pressure</em> <em>favor homozygous</em>. In equilibrium, <em>the two alleles might be present or one of them might be lost</em>. If an environment has two extremes, then in these environments, both alleles are presented in homozygous.
The disruptive selection causes an <em>increase</em> in the two types of <em>extreme phenotypes over the intermediate forms</em>. Limits between one extreme and the other are frequently very sharped. Individuals belonging to one phenotype can not live in the same area as individuals belonging to the other phenotype, due to the traits differences between them, competition, or predation.
Populations show two favored extreme phenotypes and a few individuals in the middle. Individuals who survive best are the ones who have traits on the <u>extremes forms</u>. Individuals in <u>the middle</u> are not successful at survival or reproduction.
<em>Color</em> is very important when it comes to <em>camouflage</em>. Dark green caterpillars that live in dark foliage and light green caterpillars that live in light foliage can <em>hide from predators</em> more effectively and will live the longest. Intermediate colored green caterpillars that don't camouflage or blend into either will be eaten more quickly.