When an individual is dehydrated, his or her intravenous fluids should be isotonic, because either a hypertonic or hypotonic IV would both cause damage to the individual’s red blood cells. Isotonic solutions are used: to increase the EXTRACELLULAR fluid volume because of blood loss, surgery, dehydration, fluid loss that has been loss extracellularly.
Where something is located
Answer:
Answer is C.
Explanation:
A. The vessel length is pretty much constant. The body can't length or shorten blood vessels.
B. Blood viscosity is also fairly constant because the composition of blood cannot change quickly enough to change resistance as needed.
C. This is the main way resistance is controlled. The smooth muscle surrounding blood vessels can rapidly respond to hormonal or metabolic stimuli and contract/relax to adjust diameter.
D. Again, temperature is fairly constant in the body and would not be a good way to alter resistance.
