Which of the following is one of the body's first lines of defense against infection?

A) antibodies
B) obstacles such as skin and mucous membranes
C) increased production of certain hormones
D) decreased heart rate


B

Biology & Microbiology

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Why is energy required for nutrient transport? Give an example of a system that transports nutrients and describe what source of energy is used to move the nutrients into the cell

What will be an ideal response?

Biology & Microbiology

Activity of the cerebral hemispheres is coordinated by signals that flow both ways across the ________

a. cerebellum b. midbrain c. optic nerve d. corpus callosum

Biology & Microbiology

You begin an experiment involving metabolic processes in human liver cells, but you discover your liver tissue samples have been contaminated with a strain of obligate anaerobic bacteria. Theoretically, how could you kill the bacteria while minimizing damage to the liver cells?

a. soak the tissue samples in pure ethanol b. put the sample through an autoclave c. expose the samples to gaseous oxygen d. dehydrate the tissue samples overnight

Biology & Microbiology

Which of the following statements relate to natural selection?

A) Populations experience differential reproductive success. B) Breeding is done intentionally with the intent to increase the frequency of desired traits. C) Variation within a population is heritable. D) Populations experience competition for resources. E) The variations in a population make no difference in terms of reproductive success.

Biology & Microbiology