What keeps the alveoli open so that gas exchange can take place?
Select one:
a. rings of cartilage
b. surfactant
c. smooth muscle
d. mucus
e. air
b. surfactant
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Behavioral traits are useful in distinguishing among species because
a. behaviors are always genetically determined. b. courtship behaviors and timing of mating may create prezygotic isolation. c. behaviors are easy to assess in dead and fossilized specimens. d. behaviors are independent of morphological characteristics. e. behaviors are always learned
Which one of the following structures degenerates if a fertilized egg does not embed in the uterus?
A) ovary B) oviduct C) zona pellucida D) corpus luteum E) secondary oocyte
Which type of organism would exhibit optimum growth at room temperature?
A) Psychrophiles B) Psychrotrophs C) Mesophiles D) Thermophiles
What type of DNA map is most detailed?
A. Sequence B. Physical C. Linkage D. Chromosomal E. Geographical