River blindness is caused by ________

a. infectious amoebas
b. Chlamydia trachomatis, an infectious bacterium
c. syphilis
d. roundworms transmitted by biting flies


d

Biology & Microbiology

You might also like to view...

Which digestive structure in humans is active in both the digestion of food and the absorption of

nutrients?

a. mouth b. liver c. pancreas d. small intestine e. stomach

Biology & Microbiology

Which of the following types of light microscopy improves the resolution of thick specimens by illuminating one plane of the specimen at a time?

A) fluorescence microscopy B) phase-contrast microscopy C) confocal microscopy D) differential interference contrast microscopy E) brightfield microscopy

Biology & Microbiology

Tandem repeat sequences found at the ends of chromosomes, such as TTAGGG as found in vertebrates, are known as ________

Fill in the blank(s) with correct word

Biology & Microbiology

Which of the following would be revealed by a comparison of a cancer cell and a normal cell?

a. Regulation of mitosis is strictly regulated in cancer cells; mitosis is unregulated in normal cells. b. Cancer cells undergo contact inhibition; normal cells do not. c. Cancer cells do not undergo contact inhibition; normal cells do. d. Cancer cells cannot metastasize; normal cells can.

Biology & Microbiology