The partial pressure of carbon dioxide is greatest in
A) venous blood.
B) alveolar air.
C) expired air.
D) inspired air.
E) arterial blood.
Question 2
Which of the following produces a lipid-rich secretion that prevents the upper and lower eyelids from sticking together at their edges?
A) palpebra
B) lacrimal caruncle
C) chalazion
D) tarsal gland
E) conjunctiva