Exam (elaborations)
Biology 117 Exam 1 (practice questions with 100- correct answers)
- Course
- Institution
Biology 117 Exam 1 (practice questions with 100- correct answers)
[Show more]
Content preview
Biology 117: Exam 1(practice questions with
100% correct answers)
What is an adaptation?
A trait that improves the fitness of its bearer, compared with
individuals without the trait
How can biological fitness be estimated?
Count the number of healthy, fertile offspring produced by different
individuals in a population.
What is true about natural selection?
-Variation exists in populations (all individuals are NOT the same).
-There is differential reproductive success within populations, i.e.
some individuals have more offspring than others.
-The fittest individuals leave the most offspring.
What is not true about natural selection?
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 the main driving force behind natural selection?
The environment
True or false?: New traits in a population arise (come into existence)
in response to need (i.e. NEED can evoke new alleles in a
population).
False
New alleles originate from _______.
mutations
Allele frequencies change as a result of __________.
,-Mutation
-Genetic drift
-Gene flow (immigration/emigration)
-Natural selection
True or false?: Changes in a population occur through small changes
in individual members of a population over a very long period of
time.
True
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 _____.
A. mosquitoes that survive spraying develop an immunity to the
insecticide
B. the original spraying has caused a permanent mutation, giving
the insects genetic resistance to the spray
C. many mosquitoes today are descendants of mosquitoes with
insecticide-resistant characteristics
D. mosquitoes are deliberately adapting themselves to this man-
made change in the environment
E. none of the above
C. many mosquitoes today are descendants of mosquitoes with
insecticide-resistant characteristics
We have an expert-written solution to this problem!
Which of the following statements concerning evolution is correct?
A. When individuals change in response to challenges from the
environment, their altered traits are passed on to offspring.
B. Species are created independently of each other and do not
change over time.
C. Populations--not individuals--change when natural selection
occurs.
D. The traits of populations become more perfect over time.
C. Populations--not individuals--change when natural selection
occurs.
What factor most accurately measures an organisms fitness?
,How many fertile offspring it produces
What is true about the frequency with which traits get passed to the
next generation?
Traits that make individuals more reproductively successful will be
passed on to the next generation with the highest frequency.
True or false?: Natural selection creates perfect organisms.
False
__________ evolve.
A. Populations
B. Individuals
A. Populations
A population of frogs resides in Cheat Lake. The majority of this
population has an average leg length of 4 inches. A new species of
flying insect appears in the area and the frog population increases
due to the availability of the new food source. The insects are fast
flyers and the frogs that are able to catch these insects need
greater leg power to jump higher and faster than previous
generations. Over time, the average leg length of frogs in Cheat
Lake becomes 6 inches. This is an example of what type of
selection?
A. Stabilizing selection
B. Directional selection
C. Oscillating selection
D. Disruptive selection
E. Temporal isolation
B. Directional selection
What graph represents directional selection?
A
What graph represents stabilizing selection?
B
, What graph represents disruptive selection?
C
Below are figures that show a range of mouse fur colors in a
population and the relative number of individuals with fur colors
across the range. The figure on the right shows the distribution
after selection, after the population has evolved and phenotypes
have changed due to selection pressures. The figure on the left
shows the distribution during (or at the onset of) selection.
Which mice have the highest fitness during selection?
Mice with dark fur color
An earthquake hits a small island. All but a small group of
genetically similar lizards are eliminated, and the survivors
reproduce and spread out over the island. This is an instance of
_____.
A. mutation
B. population bottleneck
C. founder effect
D. nonrandom mating
B. population bottleneck
A population of squirrels is preyed upon by small hawks. The
smaller squirrels can escape into burrows. The larger squirrels can
fight off the hawks. After several generations, the squirrels in the
area tend to be very small or very large. What process is
The benefits of buying summaries with Stuvia:
Guaranteed quality through customer reviews
Stuvia customers have reviewed more than 700,000 summaries. This how you know that you are buying the best documents.
Quick and easy check-out
You can quickly pay through credit card or Stuvia-credit for the summaries. There is no membership needed.
Focus on what matters
Your fellow students write the study notes themselves, which is why the documents are always reliable and up-to-date. This ensures you quickly get to the core!
Frequently asked questions
What do I get when I buy this document?
You get a PDF, available immediately after your purchase. The purchased document is accessible anytime, anywhere and indefinitely through your profile.
Satisfaction guarantee: how does it work?
Our satisfaction guarantee ensures that you always find a study document that suits you well. You fill out a form, and our customer service team takes care of the rest.
Who am I buying these notes from?
Stuvia is a marketplace, so you are not buying this document from us, but from seller FREEMANSHARP. Stuvia facilitates payment to the seller.
Will I be stuck with a subscription?
No, you only buy these notes for $15.49. You're not tied to anything after your purchase.
Can Stuvia be trusted?
4.6 stars on Google & Trustpilot (+1000 reviews)
75057 documents were sold in the last 30 days
Founded in 2010, the go-to place to buy study notes for 14 years now
