1) When experimentally applying alpha-bungarotoxin to a muscle,
you find that it does not contract when the motor neuron leading to
it is electrically stimulated. Knowing that this toxin blocks
acetylcholine receptors, what can you conclude about the failure to
contract?

A) None of the statements concerning alpha -bungarotoxin are
correct.

B) A contraction fails to occur because this toxin directly
prevents calcium ion release from intracellular stores.

C) A contraction fails to occur because an action potential is
not initiated in the muscle cell.

D) A contraction fails to occur because neurotransmitter fails
to be released by the motor neuron.

E) A contraction fails to occur because this toxin prevents
cross-bridge formation and thereby directly prevents
contraction.

2) Air rushes into the lungs of humans during inhalation because
?

A) pulmonary muscles contract and pull on the outer surface of
the lungs.

B) pressure in the alveoli increases.

C) smooth muscle lining the trachea, bronchi and bronchioles
contracts and causes their volume to increase.

D) the diaphragm contracts and pushes upward on the chest
cavity.

E) the volume of the thoracic cavity increases.

3) While shopping at your local drugstore, you stop at the blood
pressure machine. It measures your blood pressure as 115/75
(good—that’s healthy!). This number means that

A) arterial pressure is 115 mm Hg when the atria contract and 75
mm Hg in between atrial contractions.

B) arterial pressure is 75 mm Hg when the ventricles contract
and 115 mm Hg in between ventricular contractions.

C) your sinoatrial node generates a 115 mV signal and your
atrioventricular node generates a 75mV signal.

D) your sinoatrial node generates a 75 mV signal and your
atrioventricular node amplifies this to a 75 mV signal.

E) arterial pressure is 115 mm Hg when the ventricles contract
and 75 mm Hg in between ventricular contractions.

4) The response to touch by such plants as the sensitive plant
is due to

A) auxin displacement in the touched area.

B) effect of gibberellins on the area affected.

C) changes in water content of cells.

D) sensitive responder cells.

5) What would a scientist see when looking through a microscope
at a piece of shoulder muscle?

A) striations with branched fibers

B) striations with unbranched fibers

C) no striations and branched fibers

D) no striations and unbranched fibers

E) The scientist would see none of the above features in
shoulder muscle