The total volume of the gas-exchanging region in the lung is called alveolar volume.
The alveolus is an air sack-like organ in the end of the respiratory airway. The alveolus is the site where gas-exchanging happens, so only air inside alveolus that will undergo actual exchange. Air in bronchus or trachea wouldn't do exchange
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.
Deoxyribonucleic (DNA) pronouced (de-ok" si-ri"bo-nu-kle'ik). It is a Nucleic Acid. DNA is one of two major classes of molecules, the other is RNA. Typically, DNA is found in the nucleus (control center) of the cell, where it constitutes the genetic material, or genes.
<span>DNA is a long, double stranded polymer-a double chain of nucleotides.</span>
Well, they are made of cells, they obtain and use energy, they grow and develop, they reproduce, they respond AND adapt to their environment, c:
