Which by-product of photosynthesis was important in altering the atmosphere of the earth so that aerobic organisms could evolve?
A) methane
B) oxygen
C) carbon dioxide
D) nitrogen
E) fructose
B) oxygen
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Which of the following statements about malaria is false?
A. Fertilization occurs within a mosquito. B. Merozoites are found inside red blood cells. C. Gametocytes develop from merozoites. D. Sporozoites are only found within a mosquito. E. Gametocytes are passed to a feeding mosquito.
Most of the somatic cells in the body are structurally and functionally specialized and do not divide
a. True b. False
Sensory neurons release glutamate and neuropeptides such as ____ to enhance the effect of glutamate
a. GABA b. substance P c. serotonin d. norepinephrine e. epinephrine
When a plant responds to external stimuli, such as light, gravity, or touch by directional growth, these responses are
referred to as: a. turgor movements. b. sleep movements. c. nastic movements. d. circadian rhythms. e. tropisms.