The pacemaker is which of the following nodes?
a. sinoatrial
b. semilunar
c. atrioventricular
d. inferior vena cava
e. superior vena cava
Answer: a
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The male reproductive whorl of a flower typically consists of one or more ____
a. petals b. carpels c. stamens d. receptacles e. sepals
An insect lays eggs inside another organism and the young consume the tissues of the living host. This is an example
of a(n)____.
a. parasite b. fundamental niche c. parasitoid d. mutualist e. carnivore
Plant cells release hydrogen ions and oxygen from
H2O molecules in a. photosystem I. b. photosystem II. c. cyclic photophosphorylation. d. light independent reaction. e. carbon fixation.
Which characteristic is associated with hardwood species?
A. Thick cuticles B. Susceptibility to periodic fires C. Needle-shaped leaves D. Recessed stomata E. Adaptations for conserving water