Crossing over produces modern combinations of alleles. Not unused alleles but unused combinations which can result in modern phenotypes or expanded assortment of phenotypes. This way the there's expanded genotype/phenotype variety but the genuine qualities are still the same ones.
The term is called THEORY.
In scientific investigation, a theory is a well substantiated explanation of how a particular phenomenon works based on the set of facts which had been repeatedly confirmed through observations and experiments. A scientific theory gives reliable account of a phenomenon.
The two principal types of connective tissue in a
muscle are collagen and myofibrils. The entire muscle is wrapped in collagen to
form a fascicle. Looking at one muscle fiber, you will see that almost the
entire cross section of the muscle fiber is composed of long, cylindrical
strands of proteins called myofibrils<span>. </span>
Answer:
The binding of ACh to the muscarinic receptor indirectly affects the permeability of K⁺channels. This can produce hyper polarization in some organs if channels are opened, and depolarization in others if channels are closed.
Explanation:
For example, in the heart it is the beta-gamma compound that fixes to the K+ channels of heart muscle and sources them to exposed. This leads to K+ dispersion out of the cell and the cell converts into hyper polarized consequential in a reduction in heart rate. In contrast, in smooth muscle of the stomach the alpha sub unit fixes to K+ channels producing them to close. This decreases the external diffusion of K+ and the cell converts depolarized ensuing in smooth muscle contraction.
Surface to volume i think