Bristle worms are found primarily in marine environments and characteristically have parapodia. Which class do they belong to?
a. Cestoda
b. Oligochaeta
c. Hirudinea
d. Polychaeta
Ans: d. Polychaeta
You might also like to view...
Nonenveloped viruses most often gain access to eukaryotic host cells by
A. fusion with the host cell plasma membrane followed by entrance of the nucleocapsid into the cytoplasm. B. nucleic acid injection through the plasma membrane. C. endocytosis. D. pinocytosis.
Humans contract Chagas disease when the reduviid bug defecates while taking a blood meal and the parasites in the feces are rubbed or scratched into the bite wound or onto mucosal surfaces. Which stage in the blood infects the host cells?
a. Amastigote b. Epimastigote c. Trypomastigote d. Promastigote
Amoxicillin is very effective for treating infections with Gram-positive bacteria but rarely causes side effects in humans. This is an example of
A) selective toxicity. B) narrow spectrum of action. C) a broad-spectrum antimicrobial. D) antibiotic resistance. E) altruism.
Which of the following is a distinct advantage of active immunity over passive immunity?
A. Active immunity provides IgG whereas passive immunity provides IgM. B. Active immunity enables the development of immunologic memory, whereas no memory develops with passive immunity. C. Active immunity develops very quickly whereas passive immunity may take months to develop. D. Active immunity is always natural whereas passive immunity is frequently artificial.