Answer:
A scientist who studies water and its properties is a hydrologist.
Explanation:
A hydrologist is a scientist linked to the study of water, both surface and underground, detecting cleanliness or contamination and proposing alternatives for its cleaning and conservation.
A hydrologist's research on the properties of water, its location, distribution and circulation contributes to the maintenance of the environment.
The other options are not correct because:
<em> A) </em><u><em>Entomologist
</em></u><em>: a scientist who studies insects.</em>
<em> B) </em><u><em>Chemist
</em></u><em>: a professional who studies the elements and chemical compounds and their properties.</em>
<em> D) </em><u><em>Oceanographer</em></u><em>
: study both oceans and seas, and their relationship with the environment, the atmosphere and the land.</em>
<em> E) </em><u><em>Toxicologist</em></u><em>: study the effects of toxic or harmful substances on living beings and the environment.</em>
The ocean waters at the equator are warm because they receive more of the sun rays than the waters at the at the poles. Therefore, the water in these regions is less dense than those at the poles. The oceans currents, moving towards the poles from the equator, move on the surface waters while those from the poles move on the ocean floor.
As the warm currents move to the poles and cool, they become more saline because they become more concentrated with salts –saturation point lowers with temperatures. At the poles, most of the salts in ejected from the waters as brine as the water sinks to the ocean floor due to density.
This movement of water currents in such circular motion forms the Thermohaline Circulation. Heat on the planet is distributed in this way.
Answer: When norepinephrine binds to alpha receptors of the iris of the eye, it causes contraction of the ciliary muscles of the eye which brings about pupil dilation.
Stimulation of alpha receptors of the smooth muscle vasculature results in vasoconstriction of blood vessels.
Explanation: Alpha receptors are adrenergic receptors that respond to norepinephrine. They are subdivided into two (2) types:
Alpha 1, found in smooth muscle heart, liver, pregnant uterus, male sexual organs and blood vessels, with effects including vasoconstriction, intestinal relaxation, uterine contraction and papillary dilation.
Alpha 2, found in platelets, vascular smooth muscle, nerve termini and pancreatic islets, with effects including platelet aggregation, vasoconstriction and inhibition of norepinephrine release and of insulin secretion.