Vascular plants and air-breathing animals first appeared during which time period?
a. Silurian period
b. Permian period
c. Cambrian period
d. Ordovician period
e. Cretaceous period
ANSWER: a
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Behavior that is entirely controlled by genes and has no learning component is
(a) learned. (b) habituated. (c) instinctive. (d) classically conditioned.
The earliest photosynthetic organisms did not
generate
a. energy. b. oxygen. c. DNA. d. proteins. e. nucleotides.
In the carbon cycle, one of the ways in which carbon is returned to the atmosphere is by respiration
____________________ Indicate whether the statement is true or false.
According to the biological species concept, which of the following statements is not correct?
(A) To be considered a species, a population must be reproductively isolated from other species (B) For a new species to arise, it must be geographically isolated from its parent species for long periods of time (C) Organisms that are phenotypically identical yet have distinct mating behavior are considered distinct species since they do not naturally interbreed (D) Organisms that can interbreed and produce sterile offspring are considered distinct species