Answer:
I, II, III
Explanation:
A threshold stimulus is a stimulus that is capable to produce a response in excitable tissues such as neurons and muscle fibers. At threshold potential, the outward movement of K+ and inward movement of Na+ become equal to each other. When the potential exceeds the threshold potential, more and more Na+ enter the cell to depolarize it and to allow the opening of Na+ channels. Therefore, to fire an action potential, the threshold must be exceeded.
Conduction of action potential is all or none phenomenon which means that either it occurs or it does not occur. As an impulse is passed by each successive part of an exon, it enters the refractory period during which there is no conduction of nerve impulse. It ensures the one-way conduction of impulse from the cell body to the axon terminal only.
The land and the aquatic are the two types of global food webs
Answer: Gastroenterology
Explanation: Gastroenterology is a branch of medicine concerned with digestive diseases. The practice of gastroenterology concentrates on the diagnosis and treatment of diseases involving the esophagus, stomach, small intestine, and large intestine (colon), liver, and pancreas. Examples of conditions treated: Abdominal pain.
by the law of natural selection, daddy charles darwin stated that overpopulation could result in famine and wars, and death would accelerates across nations, so overpopulation is a cause for this because of too many organisms but not enough food, which declined growth rate.
Answer:
Sea water
Explanation:
Because sea water has many impurities