The absence of ________ in the primitive atmosphere was essential to the origin of life on Earth
A) N2
B) CO2
C) CH4
D) O2
D
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Trichomoniasis is the primary nonviral sexually transmitted disease worldwide. One complication of this infection is:
a. keratitis. b. endometritis. c. meningitis. d. appendicitis.
The process that forms the electrochemical gradient during photosynthesis is the
A. pumping of H+ into the thylakoid lumen. B. hydrolysis of ATP. C. movement of water by osmosis. D. production of water from oxygen in the thylakoid lumen. E. production of H+ in the stroma during NADPH production.
Which young develop briefly in their mother's body, nourished by egg yolk and by nutrients that diffuse from the mother's tissues?
a. nonbird reptiles b. birds c. monotremes d. marsupials e. placentals
Where in the brain is the corpus callosum?
a. between the cerebellum and the medulla oblongata b. below the cerebellum c. between the two hemispheres of the cerebrum d. between the pons and the midbrain e. between the thalamus and the hypothalamus