BIO 117 Exam 1 questions and
answers rated A+
What is an adaptation? - correct answer ✔✔ a trait that improves the fitness of its bearer,
compared with individuals without the trait
How can biological fitness be estimated? - correct answer ✔✔ Count the number of healthy,
fertile offspring produced by different individuals in a population.
All of the following are true for natural selection EXCEPT:
- Variation exists in populations (all individuals are NOT the same).
-Characteristics acquired by individuals over the course of their lifetime, e.g. big muscles from
weight lifting are passed on to their offspring.
-There is differential reproductive success within populations, i.e. some individuals have more
offspring than others.
-The fittest individuals leave the most offspring. - correct answer ✔✔ Characteristics acquired
by individuals over the course of their lifetime, e.g. big muscles from weight lifting are passed
on to their offspring.
What is a main driving force behind natural selection? - correct answer ✔✔ The environment
Vestigial traits are _____. - correct answer ✔✔ remnants of structures that were useful to an
organism's ancestors
TRUE/FALSE: New traits in a population arise (come into existence) in response to need (i.e.
NEED can evoke new alleles in a population). - correct answer ✔✔ False
, New alleles originate from _______. - correct answer ✔✔ mutations
According to ________, traits acquired during an individual's lifetime will be inherited by
offspring. - correct answer ✔✔ Lamarck
Allele frequencies change as a result of __________.
-Mutation
-Genetic drift
-Gene flow (immigration/emigration)
-Natural selection
-All of the above - correct answer ✔✔ All of the above
TRUE/FALSE: Changes in a population occur through small changes in individual members of a
population over a very long period of time. - correct answer ✔✔ True
Animals that possess homologous structures probably _____. - correct answer ✔✔ evolved
from the same ancestor
When they were first sold, aerosol insecticides were highly effective in killing flies and
mosquitoes. Now, several decades later, a much smaller proportion of these insects die when
sprayed. The reason fewer insects die when they are sprayed is that _____. - correct answer
✔✔ many mosquitoes today are descendants of mosquitoes with insecticide-resistant
characteristics
Which of the following statements concerning evolution is correct?
-When individuals change in response to challenges from the environment, their altered traits
are passed on to offspring.
-Species are created independently of each other and do not change over time.
-Populations--not individuals--change when natural selection occurs.
answers rated A+
What is an adaptation? - correct answer ✔✔ a trait that improves the fitness of its bearer,
compared with individuals without the trait
How can biological fitness be estimated? - correct answer ✔✔ Count the number of healthy,
fertile offspring produced by different individuals in a population.
All of the following are true for natural selection EXCEPT:
- Variation exists in populations (all individuals are NOT the same).
-Characteristics acquired by individuals over the course of their lifetime, e.g. big muscles from
weight lifting are passed on to their offspring.
-There is differential reproductive success within populations, i.e. some individuals have more
offspring than others.
-The fittest individuals leave the most offspring. - correct answer ✔✔ Characteristics acquired
by individuals over the course of their lifetime, e.g. big muscles from weight lifting are passed
on to their offspring.
What is a main driving force behind natural selection? - correct answer ✔✔ The environment
Vestigial traits are _____. - correct answer ✔✔ remnants of structures that were useful to an
organism's ancestors
TRUE/FALSE: New traits in a population arise (come into existence) in response to need (i.e.
NEED can evoke new alleles in a population). - correct answer ✔✔ False
, New alleles originate from _______. - correct answer ✔✔ mutations
According to ________, traits acquired during an individual's lifetime will be inherited by
offspring. - correct answer ✔✔ Lamarck
Allele frequencies change as a result of __________.
-Mutation
-Genetic drift
-Gene flow (immigration/emigration)
-Natural selection
-All of the above - correct answer ✔✔ All of the above
TRUE/FALSE: Changes in a population occur through small changes in individual members of a
population over a very long period of time. - correct answer ✔✔ True
Animals that possess homologous structures probably _____. - correct answer ✔✔ evolved
from the same ancestor
When they were first sold, aerosol insecticides were highly effective in killing flies and
mosquitoes. Now, several decades later, a much smaller proportion of these insects die when
sprayed. The reason fewer insects die when they are sprayed is that _____. - correct answer
✔✔ many mosquitoes today are descendants of mosquitoes with insecticide-resistant
characteristics
Which of the following statements concerning evolution is correct?
-When individuals change in response to challenges from the environment, their altered traits
are passed on to offspring.
-Species are created independently of each other and do not change over time.
-Populations--not individuals--change when natural selection occurs.
