I believe the correct answer would be <span>variation. The definition of variation in biology means,</span><span> any difference
between cells, individual organisms, or groups of organisms of any
species caused either by genetic differences or by the effect of environmental factors on the expression of the genetic potentials. So i think that organisms can also be classified as variation. Hope this helped. ♥ ☺
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Darwin's idea of the survival of the fittest means that certain organisms are more likely to survive with they traits in particular environments. This is because some organisms are more fit to live in a given environment whether it be due to temperature, weather, or predators.
One example is that dark moths are more fit for survival than light moths in many areas because they are able to camouflage against dark tree bark.
Hope this helps.
B)Mendelian genes are at specific loci on the chromosome and,in turn, segregate during meiosis.
Epinephrine is also known as adrenaline. It is produced by both the adrenal glands and the certain neurons. It is used to treat some conditions like cardiac arrest, anaphylaxis and more. Its actions vary by tissue type and tissue expression of then receptors. It is binding to a variety of adrenergic receptors.It also help to increase peripheral resistance.