Answer: Acetylcholine.
Explanation: Acetylcholine is a neurotransmitter that mediates many sinaptic functions in nervous system. When a motor neuron releases acetylcholine at the neuromuscular junction, it binds to nicotinic receptors in muscular fibers and activates a signal cascade that will free intracellular calcium ions, causing the contraction of the muscular fibers.
The percentage of progenies with red eyes and spine will be 56.25%.
<h3><u>Explanation:</u></h3>
This cross will be just similar to Mendel’s Dihybrid cross where he crossed the pea plants considering two characters at once.
Here two characters that are taken into account are eye colour and presence of spine. The eye colour has two traits - red and brown. Red colour is dominant. The presence of spine has also two possibilities - presence of spine or absence of spine.
The allele denoting red eye colour is R and allele denoting brown eye colour is r. Similarly, the allele denoting presence of spine is S and absence of spine is s.
Genotype of the heterozygous parents = RrSs.
Gametes produced by the parents= RS, Rs, rS and rs.
So crossing them, we get the phenotypic ratio of red eyed spined : red eyed spineless : brown eyed spined : brown eyed spineless = 9:3:3:1.
So, the percentage of red eyed spined = 56.25%.
Old existing cells.......
Answer:
cell Parts Analogy. The cell membrane controls what goes in and out of the cell. The cell membrane is like a screen door, because a screen door holds things out but lets air in.