The structure shown by the red arrow is cell membrane.
In biology, cell membrane refers to the thin layer, which develops the external boundary of a living cell. It has three primary functions, which are as follows:
1. It comprises channels and receptors, which permits particular molecules like nutrients, ions, metabolic components, and wastes to pass between the cell and the outside environment.
2. It prevents toxic components from entering the cell.
3. They distinguish essential but incompatible metabolic procedures conducted within the cell.
C. transporting nutrients to cells
It's important so that they know exactly where the disease started. Knowing who patient zero is helps them to identify who that person interacted with. From there, they can determine where the disease spread to. This will aid them in stopping the disease before it spreads any further.
Acid rain<span> is caused by a </span>chemical<span> reaction that begins when compounds like sulfur dioxide and nitrogen oxides are released into the air. These substances can rise very high into the atmosphere, where they mix and react with water, oxygen, and other </span>chemicals<span> to form more </span>acidic<span> pollutants, known as </span>acid rain<span>.</span>
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.
