Answer:
A. Natural
Explanation:
The moon orbits Earth just like Earth orbits the sun. The moon is Earth's only natural satellite.
Answer:
A. Botulinum toxin possesses a heavy chain and a light chain, each of which takes part in the toxicity. The binding of the protein and its invasion within a nerve cell is permitted by the heavy chain. After the entry is permitted, the light chain functions like a protease and chops proteins, which would usually permit neurotransmitters to discharge out from the cell. This is basically a commotion of exocytosis or the discharging of neurotransmitters.
The acetylcholine, that is, the obstructed neurotransmitter generally conducts a nerve impulse to a muscle, allowing the muscle to contract. By inhibiting the neurotransmitter, the botulinum toxin results in its distinctive flaccid paralysis.
B. The small doses of the sterile, purified botulinum toxin when used in a medical setting as an injectable form prevent the release of a chemical known as acetylcholine by the nerve cells, which signal contraction of the muscles. By selectively interfering with the underlying tendency of the muscles to contract, the prevailing frown lines are smoothed out, and in the majority of the cases are almost invisible for a week.
Human skin color is a polygenic trait, which means that multiple gene loci (with different alleles) are involved in its expression. It has been shown that there more than 350 genetic loci involved in determining skin color. Because of that, there is the enormous number of possible genotypes for the skin color and as a result, the phenotypes vary from the darkest brown to the lightest hues. Different populations have different allele frequencies of genes for human skin color, and the combination of these allele variations brings about complex and continuous variation in skin coloration. Natural skin color can change due to exposure to sunlight (becomes darker) and that is the way it adapts to intense sunlight irradiation (protection against the UV exposure).
plz mark as brainlist
Answer:
the diagram shows the body structures that are similar though in different species due to common ancestry, this evidence is comparative anatomy.
