In humans and many other animals, what organ system is involved in bulk transport of nutrients, oxygen, and signaling molecules?
A. respiratory system
B. circulatory system
C. immune system
D. digestive system
B
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Classically, nature and nurture have been considered as two very separate factors impacting phenotype. Considering
what we have learned of methylation, is this always the case? What will be an ideal response?
Endocarditis is often a consequence of bacteria attached to the heart valves. These microbes are not eliminated by circulating lymphocytes because
A. lymphocytes do not circulate through the heart valves to detect the presence of microbes. B. Gram-positive microbes don't have an exotoxin surface molecule to trigger an immune response. C. these microbes become covered in platelets and fibrin which is not recognized as foreign by the immune system. D. lymphocytes cannot engulf microbes attached to tissue.
A flower forms from
a. an ovary tissue that migrates from the root. b. stem cells that form tumor like growths. c. impregnated pollen grains. d. a modified branch called a receptacle. e. bark tissue.
All of the following are usually a part of the aging of reproductive systems EXCEPT ____
a. declining levels of estrogen b. menopause c. loss of sexual response d. decreased fertility e. declining testosterone levels