Answer:
A- Acetylcholine is released by axon terminals of the motor neuron.
Explanation:
The general mechanism of muscle contraction can be explained as follows:
a) The action potential which is generated, travels along the motor nerve to its ends on muscle fiber (or motor end plate) at the neuro-muscular junction.
b) The nerve endings then secrete small amounts of neurotransmitter called acetylcholine.
c) The actylecholine binds to the receptors on the membrane of muscle fiber and opens the voltage gated sodium channels.
d) Opening of these channels leads to flow of large quantities of sodium ions into the muscle fiber which ultimately results in initiation of action potential in muscle fiber.
e) This action potential depolarizes the fiber including the T-tubules, triggering the release of calcium ions from sarcoplasmic reticulum.
f) The calcium ions thus released initiated the process of muscle contraction.
Answer:
A
Explanation:
Stretching of the atrium and ventricle muscles
Answer:
Aa is the strongest gene because most people have that gene aa is rarer being that it has 2 non-dominate gene materials.
Explanation:
AA is common but rarer than Aa because it has 2 dominate gene materials
Answer:DNA, RNA, Ribosomes and Protein Synthesis
This provided the first substantial evidence for the endosymbiosis hypothesis. It was also determined that mitochondria and chloroplasts divide independently of the cell they live in.
Explanation:
<em>What role did endosymbiosis play in the evolution of eukaryotes? Endosymbiosis led to the evolution of eukaryotic cells with mitochondria and chloroplasts. This kind of natural selection led to the evolution of eukaryotic cells and the plants and animals we see today.</em>
Answer:
<u><em>A diploid cell becomes haploid during Meiosis I and is completed after Telephase I. These homologous chromosomes (from mom & dad, all duplicated) pair up during prophase I forming tetrads. The pairs of homologs line up on the metaphase plate during metaphase I.</em></u>
Explanation: