BIO 100 EXAM 3 PRACTICE QUESTIONS
AND COMPLETE SOLUTIONS
◉ A city was intensively sprayed with DDT to control houseflies.
The number of houseflies was immediately greatly reduced. Each
year thereafter, the city was sprayed again, but the flies gradually
increased in numbers until 10 years later, when they were almost
as abundant as they were when the control program began. Which
of the following most likely explains this?
A) HouseFlies from other areas moved in and replaced the ones
killed by DDT
B) DDT is only effective in dry years. Eventually another very dry
year will occur and DDT will again wipe out the house flies in the
city
C) DDT caused new mutations to occur in the surviving house flies
resulting in resistance to DDT
D) few house flies that were affected by DDT but survived
developed antibodies to DDT , which they passed on to their
descendants
E) The DDT killed most house flies. The few that were already
naturally resistant survived and passed this resistance on
Answer: E
◉ In which of the following ways does xylem contribute to the
reproductive success of Plants?
,A) water transport, support against downward pull of gravity
B) anchorage, starch storage
C)Water transport, sugar transport
D) Flowering, starch storage
E) Water transport, anchorage
Answer: A
◉ Anthropoids molt
A) once a year to keep their outsides shiny
B) when they move from water out onto land
C) when males are about to fight other males
D) to shed exoskeletons of particular sizes so as to grow new,
bigger ones, as they grow bigger
E) to get rid of parasitic fungi
Answer: D
◉ If the figure above depicts relationships within a particular
animal lineage, the branching points of the tree most commonly
represent
A) convergent evolution
B) allopathic speciation events
C) The passage of 1000 years
D) convolution
E) stabilizing selection
, *See photo spring 2017
Answer: B
◉ Animals that possess homologous structures
A) have been subjected to similar environmental conditions
B) evolved from a common ancestor
C) by chance had a similar mutation in the past
D) Are not related
E) are headed for extinction
Answer: B
◉ Cephalization results in an animal's being able to sample the
environment in front of it and make choices about directions in
which to travel. Of the following which is the first group of
animals to "move with intent"?
A) mollusks
B) flatworms
C) vertebrates
D) nematodes
E) cnidarians
Answer: B
◉ Which of the following is true?
AND COMPLETE SOLUTIONS
◉ A city was intensively sprayed with DDT to control houseflies.
The number of houseflies was immediately greatly reduced. Each
year thereafter, the city was sprayed again, but the flies gradually
increased in numbers until 10 years later, when they were almost
as abundant as they were when the control program began. Which
of the following most likely explains this?
A) HouseFlies from other areas moved in and replaced the ones
killed by DDT
B) DDT is only effective in dry years. Eventually another very dry
year will occur and DDT will again wipe out the house flies in the
city
C) DDT caused new mutations to occur in the surviving house flies
resulting in resistance to DDT
D) few house flies that were affected by DDT but survived
developed antibodies to DDT , which they passed on to their
descendants
E) The DDT killed most house flies. The few that were already
naturally resistant survived and passed this resistance on
Answer: E
◉ In which of the following ways does xylem contribute to the
reproductive success of Plants?
,A) water transport, support against downward pull of gravity
B) anchorage, starch storage
C)Water transport, sugar transport
D) Flowering, starch storage
E) Water transport, anchorage
Answer: A
◉ Anthropoids molt
A) once a year to keep their outsides shiny
B) when they move from water out onto land
C) when males are about to fight other males
D) to shed exoskeletons of particular sizes so as to grow new,
bigger ones, as they grow bigger
E) to get rid of parasitic fungi
Answer: D
◉ If the figure above depicts relationships within a particular
animal lineage, the branching points of the tree most commonly
represent
A) convergent evolution
B) allopathic speciation events
C) The passage of 1000 years
D) convolution
E) stabilizing selection
, *See photo spring 2017
Answer: B
◉ Animals that possess homologous structures
A) have been subjected to similar environmental conditions
B) evolved from a common ancestor
C) by chance had a similar mutation in the past
D) Are not related
E) are headed for extinction
Answer: B
◉ Cephalization results in an animal's being able to sample the
environment in front of it and make choices about directions in
which to travel. Of the following which is the first group of
animals to "move with intent"?
A) mollusks
B) flatworms
C) vertebrates
D) nematodes
E) cnidarians
Answer: B
◉ Which of the following is true?
