In small aquatic animals, such as hydra and planarians, the most common structure used for gas exchange is the

A. cardiovascular system.
B. body surface.
C. gills.
D. lungs.


Answer: B

Biology & Microbiology

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The member of the normal microbiota sometimes considered responsible for tinea versicolor is

A. staphylococci. B. diptheroids. C. Candida spp. D. Malassezia spp.

Biology & Microbiology

Which statement about carbohydrates is true?

a. Carbohydrates provide structural support to organisms. b. Carbohydrates are nonpolar and insoluble in water. c. All carbohydrates are considered micromolecules. d. All carbohydrates are arranged in a linear sequence.

Biology & Microbiology

Normally, a gamete gets only one of a pair of alleles. This is true because of 

A. crossing-over. B. independent assortment. C. fertilization. D. segregation.

Biology & Microbiology

Enterococcus faecalis has been associated with ________.

A. endocarditis B. sinus infection C. abscesses D. diarrhea

Biology & Microbiology