precambrian era,
a. an oxidizing atmosphere developed on earth.
b. the formation of the ozone shield occurred.
c. the amount of uv light reaching the earth was reduced and chemical evolution
slowed.
d. all of the choices are correct.
6) which of the following groups are considered chordates but are lacking the vertebral
column trait?
a. osteichthyes & urochordata
b. urochordata & cephalochordates
c. cephalochordates & chondrichthyes
d. sea squirts & chondrichthyes
7) which of the following plant hormones prevents plant tissues from senescing, or
aging?
a. abscisic acid
b. auxin
c. cytokinin
d. ethylene
e. gibberellin
8) if the calvin cycle uses three molecules of co2 to produce six molecules of g3p
(glyceraldehydes-3-phosphate), but only one g3p molecule is used to form a
carbohydrate molecule, what happens to the other carbons that were taken in?
a. any unused co2 is released into the environment.
b. the other five g3p molecules are used to regenerate more rubp.
c. any unused g3p molecule is converted and stored as starch.
d. the remaining five g3p molecules are used to reduce co2.
9) which domains did kingdom monera get divided into?