Answer:
C. is unstable, with a short half life
Explanation:
Paracrine hormones are the hormones that act on neighboring cells only. These hormones or chemicals are largely unstable and have a brief life as do not visit the distantly placed target cells. For instance, somatostatin is secreted by D cells of the pancreas. It acts in a paracrine manner and inhibits the discharge of hormones from the neighboring beta and alpha cell.
Likewise, one of the functions of unstable NO gas is to serve as a vasodilator. It is released by epithelium cells and serves to dilate arterioles and relax precapillary sphincters. Then it is degraded.
Answer: d. All the above
Fertilizers can be deterimental to the environment. Excess use of fertilizers will result in eutrophication in the water body. Water body being more enriched with nutrients will result in excessive growth of aquatic plants. This also result in algal bloom in which algae grows on the surface of water body because of this atmospheric oxygen not able to reach the aquatic plants, hence results in oxygen depletion.
Ionic, since electrons are transferred.<span />