Answer:
Neurotransmitters
Explanation:
Neurotransmitters are the chemicals present in the body used for the propagation of action potential. These neurotransmitters are also known as the body chemical messengers.
Neurotransmitters are stored in the neural cells. These chemicals are generally released when the cell is stimulated by the specific signal. The effect of neurotransmitter may be excitatory or inhibitory.
Thus, the answer is option (4).
Answer:
F: The oxygen atom has a greater attraction for the electrons in the surrounding covalent bonds than the
hydrogen atoms.
Explanation:
Between hydrogen and oxygen atoms exist a covalent bond. Oxygen is more electronegative than hydrogen atom hence its ability to get attracted to itself more electrons than hydrogen.
<span>The correct answer is A, B and D. Biogeochemical cycles are central to the ecology of earth system. They make the essentail elements accessible and available for the organisms, and maintain their levels, so that the ecology is ot disrupted. The elements move through abiotic and biotic factors, in these cycles, and a state of equilibrium is maintained n the ecosystem. The carbon dioxide levels are responsible fr the temperature of the earth. If Carbon cycles would not have existed, then there would have been a disruption in maintaining the global temperature. Biogeochemical cycles basically continuously recycles the essential materials, for sustaining the life-forms.</span>
