Answer:
The population suffered a genetic bottleneck, which decreased genetic variation and thereby randomly increasing the frequency of harmful alleles
Explanation:
A population bottleneck, also known as genetic bottleneck, can be defined as a drastic reduction in the size of a population, which may be caused by anthropic activity and/or environmental phenomena (e.g., earthquakes, famines, fires, droughts, etc). A genetic bottleneck leads to a reduction in genetic variability within a population. Moreover, the genetic drifit caused by a genetic bottleneck can also increase the frequency of harmful alleles/mutations (it is due to the random sampling of individuals), thereby increasing the frequency of deleterious alleles/mutations in the population.
Answer:
relaxes
Explanation:
Acetylcholine is the substance responsible for the transmission of nerve impulses from pre-postganglionic neurons, in the ganglia of the autonomic nervous system. At the level of the parasympathetic nervous system, the transmission between the postganglionic neuron and the effector organ also mediates. In addition, it is the mediator of the nerve transmission of the terminal motor plate.
There are large differences in the effects that Acetylcholine triggers at different cholinergic transmission sites
Intra-arterial injection near Acetylcholine produces muscle contraction similar to that caused by motor nerve stimulation. Decreased resting potential in isolated intestinal muscle and increased frequency of spike production, accompanied by increased tension. In the cardiac conduction system, nodes S-A and A-V, it produces inhibition and hyperpolarization of the fiber membrane; and pronounced decrease in depolarization speed. Central regulation of extrapyramidal motor function. Exciting effect of the basal ganglia that counteracts the inhibitory action of Dopamine. Although cholinergic innervation of blood vessels is limited, cholinergic muscarinic receptors occur in sympathetic vasoconstrictor nerves. The vasodilator effect on isolated blood vessels requires the presence of an intact endothelium. The activation of muscarinic receptors causes the release of a vasodilator substance - <u>relaxing factor derived from the endothelium - that diffuses to the smooth muscle producing </u><u>relaxation</u><u>.</u>
Answer:
Option (C).
Explanation:
The dilation of feeder arterioles carry blood directly into the blood vessels. The pre capillary sphincter in the systemic capillary beds can open due to the different factors.
The local release of histamines do not cause the dilation of feeder arterioles and does not cause the opening of systemic capillary beds. Histamine chemical is involved in the immune response of the body.
Thus, the correct answer is option (C).
