Which of the following statements concerning membrane transport across the plasma membrane is true?
A. Lipid-soluble substances pass through the membrane by dissolving in the lipid bilayer.
B. Generally, cations pass through the membrane more easily than anions.
C. Water cannot move through the membrane.
D. All molecules are moved across by active transport.
E. Polar molecules are transported more easily than nonpolar molecules.
Answer: A
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Answer the following statements true (T) or false (F)
1. The lifting of a 10-lb weight requires the activation of fewer motor units than the lifting of a 5-lb weight. 2. Twitch contractions play an important role in normal muscle activity. 3. Lifting your textbook off the desk is an example of an isotonic muscle contraction. 4. Trying to lift a car (and failing) is an example of an isotonic muscle contraction. 5. In an isometric contraction, no movement occurs but the muscle tension increases.
A granulocyte, phagocyte and the most common white blood cell found in whole blood.
A) Neutrophil B) Monocyte C) Eosinophil D) Lymphocyte
Which is a typical response of the body to hemorrhage?
A. decreasing the heart rate below normal B. decreasing total peripheral resistance to below normal levels C. raising mean arterial pressure to above normal D. increasing cardiac output to above normal levels E. increasing bulk-flow reabsorption of fluid into capillaries
Nonessential amino acids:
a. are not used by the body b. can be made by the body from other substances c. are used only for catabolism d. are found only in plant proteins