posted by mysterychicken .
19. Which is NOT a general characteristic of plants?
a. use oxygen to make usable energy
b. primary producers
c. have specialized cells
d. cell walls composed of cellulose
I think it might be either A or B...
20. Which of the following are characteristics of all animals?
a. multicellular, haploid cells that divide by mitosis, organisms with organ systems
b. multistage zygote development, vertebrates, reproduce sexually
c. 99 percent invertebrates, heterotrophs, multicellular
d. both A and C
D? Or just C?
23. A typical virus consists of a
a. protein coat and a cytoplasm core
b. carbohydrate coat and nucleic acid core
c. protein coat and a nucleic acid core
d. polysaccharide coat and protein core
24. During initial HIV infection, the HIV virus attaches to CD4 receptors on a macrophage and then
a. attaches to a CCR5 receptor before it's able to enter the cell
b. enters the cell through the CD4 receptors
c. attaches to a lymphocyte that attempts to fight the virus on the macrophage.
d. HIV tricks the reverse transcriptase of the infected cell into making copies of the viral RNA molecule.