Imagine that you are outside on a cold day and have removed your gloves to answer your phone. Which statement is true regarding
the blood vessels (directly below the surface of your skin) in your ungloved hands?a. As a result of vasodilation, these blood vessels have expanded or increased in diameter, thereby increasing amount of heat your hands are losing to the environment.b. As a result of vasodilation, these blood vessels have shrunk or contracted in diameter, thereby reducing the amount of heat your hands are losing to the environment.c. As a result of vasoconstriction, these blood vessels have shrunk or contracted in diameter, thereby reducing the amount of heat your hands are losing to the environment.d. As a result of vasoconstriction, these blood vessels have expanded or increased in diameter, thereby increasing the amount of heat your hands are losing to the environment.e. There will be no change in these blood vessels; their diameter will remain the same as when you had your gloves on.
Mammals are warm-blooded animals that are they need to maintain the internal temperature irrespective of the external temperature at a constant rate or 37° C.
In cold conditions the person exposing the body parts to cold conditions response either by producing heat or conserving the heat in the body.
If a person removes the gloves, then a physiological change leads to the change in the diameter of the blood vessels. The diameter of the blood vessels reduces which reduces the loss of heat from the body as constriction of the blood vessels decreases the surface area to be exposed to cold conditions.
Nucleic acids are the most important macromolecules for the continuity of life. They carry the genetic blueprint of a cell and carry instructions for the functioning of the cell. The two main types of nucleic acids are deoxyribonucleic acid (DNA) and ribonucleic acid (RNA).
