BIO 251 EXAM 3 STUDY GUIDE
QUESTIONS AND CORRECT
ANSWERS LATEST GUIDE 2026
GRADED A+ .
, 1. A muscle fiber can be innervated by multiple motor neurons.
a) True
b) False✓✓ Correct answer f
2. The contraction time of a skeletal muscle is the time between initiation of stimulation and
peak contraction of the muscle.
a) True
b) False✓✓ Correct answer f
3. During contraction of all types of muscle cells, Ca++ initiates contraction by entering the
cytoplasm of the muscle cell by the process of facilitated diffusion.
a) True
b) False✓✓ Correct answer t
4. The plateau phase of the contractile cell action potential is caused by Na+ entering the cell.
a) True
b) False✓✓ Correct answer f
5. The radii of arterioles can be adjusted independently to variably distribute cardiac output
among organs.
a) True
b) False✓✓ Correct answer t
6. Platelets contain actin and myosin.
a) True
b) False✓✓ Correct answer t
7. Ischemic heart disease is
a) Rapid but regular depolarizations and contractions
b) Rapid irregular uncoordinated depolarizations contractions
c) Action potentials not conducted between atria and ventricles
d) Over excitation of non-SA node autorhythmic regions of heart
e) Reduced blood supply to heart✓✓ Correct answer e
QUESTIONS AND CORRECT
ANSWERS LATEST GUIDE 2026
GRADED A+ .
, 1. A muscle fiber can be innervated by multiple motor neurons.
a) True
b) False✓✓ Correct answer f
2. The contraction time of a skeletal muscle is the time between initiation of stimulation and
peak contraction of the muscle.
a) True
b) False✓✓ Correct answer f
3. During contraction of all types of muscle cells, Ca++ initiates contraction by entering the
cytoplasm of the muscle cell by the process of facilitated diffusion.
a) True
b) False✓✓ Correct answer t
4. The plateau phase of the contractile cell action potential is caused by Na+ entering the cell.
a) True
b) False✓✓ Correct answer f
5. The radii of arterioles can be adjusted independently to variably distribute cardiac output
among organs.
a) True
b) False✓✓ Correct answer t
6. Platelets contain actin and myosin.
a) True
b) False✓✓ Correct answer t
7. Ischemic heart disease is
a) Rapid but regular depolarizations and contractions
b) Rapid irregular uncoordinated depolarizations contractions
c) Action potentials not conducted between atria and ventricles
d) Over excitation of non-SA node autorhythmic regions of heart
e) Reduced blood supply to heart✓✓ Correct answer e
