Chemical evolution started on Earth
a. after the appearance of prokaryotic cells.
b. long before any cells emerged.
c. after the appearance of eukaryotic cells.
d. after the appearance of eukaryotic cells but
before the appearance of multicellular
organisms.
e. after the appearance of multicellular
organisms.
B
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Which of the following is TRUE about the
spores of seed plants?
a. megaspores develop into female gametophytes b. meiosis produces four megaspores c. microspores enlarge to become megaspores d. megaspores are diploid cells e. microspores undergo meiosis to form four pollen grains
An adenovirus
a. is a naked virus. b. does not have a lipid envelope. c. has a spiked protein coat. d. infects animals. e. all of these.
For the following medical conditions, describe the likely cellular organelle or structure that has been
affected in such a way as to cause the condition (note: There may be more than one organelle or structure involved): A. The sperm of a man cannot swim, thus rendering him infertile. B. A child experiences kidney failure due to Fabry's disease where the cells lining the inside of the kidney tubule accumulate abnormally large amounts of glycolipids that are usually degraded by enzymes. C. A person dies within minutes after ingesting cyanide because ATP is no longer being synthesizedWhat will be an ideal response?
Which cells stimulate B cells to divide and produce antibodies?
a. mast cells b. macrophages c. NK cells d. TC cells e. TH cells