C. Solar energy's whole purpose it to reduce pollution in the air that fossil feuls do not. The answer cannot be A. B. or D. because 1. it is expensive 2. it can only be used during the daytime. It is a SOLAR panel. and 3. like is said earlier it is not free.
Answer:
What happens to energy as it flows through the food chain and food webs of an ecosystem The chemical energy storied as nutrients in the bodies and wastes of organisms flows through ecosystems from one trophic level to the next and through this flow energy also is lost as heat.Explanation:
Answer:
The antibodies produced by a vaccine only fight specific antigens.
Explanation:
Antibodies only bind to specific antigen during an immune reaction. The introduction of foreign substance in the body stimulate the B-cells to produce antibodies that fight against infections. Only specific antibodies are produced following antigen presenting cells that bind to antigens. They capture and display the antigens to the antibodies.
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.