In an elderly person, blood supply to the dermis is reduced and sweat glands are less active. This combination of factors would most affect

(a) The ability to thermoregulate

(b) The ability to heal injured skin

(c) The ease with which the skin is injured

(d) The physical characteristics of the skin

(e) The ability to grow hair

Two patients arrive at the emergency department. One has cut his finger with a knife; the other has stepped on a nail. Which wound has a greater chance of becoming infected? Why?

Exposure to optimum amounts of sunlight is necessary for proper bone maintenance and growth in children.

(a) What does sunlight do to promote bone maintenance and growth?

Exposure to optimum amounts of sunlight is necessary for proper bone maintenance and growth in children.

(b) If a child lives in an area where exposure to sunlight is rare because of pollution or overcast skies, what can be done to minimize impaired maintenance and growth of bone?

One of the factors to which lie detectors respond is an increase in electrical skin conductance due to the presence of moisture. Explain the physiological basis for the use of this indicator.

Many people change the natural appearance of their hair, either by coloring it or by altering the degree of curl in it. Which layers of the hair do you suppose are affected by the chemicals added during these procedures? Why are the effects of the procedures not permanent?