AnswersAISD-Biology B CR 25-26Natural Selection

Natural Selection Answers

10 verified answers1 views
1
Free Preview

Which are characteristics of natural selection? Select three options. It affects populations.It affects only individuals.It occurs when there is genetic variation.It occurs when organisms are genetically identical.It selects organisms with certain traits to survive.It selects organisms at random to survive.

A
It affects populations.
B
It affects only individuals.
C
It occurs when there is genetic variation.
D
It occurs when organisms are genetically identical.
E
It selects organisms with certain traits to survive.
F
It selects organisms at random to survive.
2
Free Preview

If there are only a few remaining members of an insect species living in one area, which would most likely cause this species to become extinct?

A
the introduction of new predators to the insects’ environment
B
a genetic mutation in an individual that causes it to be very small
C
a disease that causes a mother insect to die shortly after laying eggs
D
the introduction of a new food source to the insects’ environment
3

In a mouse population, some mice have thicker fur than others, but there are more mice with thinner fur. The climate in which these mice live has slowly gotten colder.

A
The adaptation of thinner fur will be selected over thicker fur, and the population will remain unchanged.
B
The adaptation of thicker fur will be selected over thinner fur, and the population will remain unchanged.
C
The adaptation of thinner fur will be selected over thicker fur, and the population will evolve.
D
The adaptation of thicker fur will be selected over thinner fur, and the population will evolve.
4

most likely

B
Bright mice were not able to blend into their environment as easily as dark mice, so they did not continue to survive and reproduce.
B
Bright mice produced fewer offspring than dark mice, so the bright mice became outnumbered within days.
R
Random changes in the genetics of bright mice produced more dark mice, so the bright mice quickly died off.
R
Random changes in the genetics of dark mice produced fewer bright mice, so the dark mice took over the population.
5

Organisms must have variation within a population in order for natural selection to occur.Which situation is an example of this variation?

A
A frog living in a pond is eaten by a predator, while others in the same population survive.
B
A snake living in a desert produces more offspring than other snakes in the same population.
C
Some rabbits living in a forest have short, spotted ears, while others have long white ears.
D
Some birds living in a grassland eat less than other birds who eat the same food.
6

Many scientists believe that dinosaurs became extinct due to

A
floods caused by strong storms.
B
a harmful genetic mutation.
C
the introduction of a predator.
D
an asteroid impact.
7

What occurs if the environment changes and a species is no longer able to survive?

A
The species becomes extinct.
B
The species evolves.
C
The species adapts.
D
The species is naturally selected.
8

Which causes genetic variations and can result in different alleles?

p
predation rate
r
random mutations
c
competition
e
environmental changes
9

Which statement best describes how reproduction leads to natural selection in a population?

A
Organisms do not produce many offspring, so all of them can survive and pass on their traits.
B
Organisms overproduce offspring; consequently, all of them are likely to survive and pass on traits.
C
Organisms overproduce offspring, so only some survive and pass on their traits.
D
Organisms do not overproduce offspring; therefore, those that are produced will develop the best traits.
10

A genetic mutation causes a squirrel to be born with much darker fur than its parents.

A
Because the trait was caused by a mutation, it will not be passed on to any offspring, resulting in the disappearance of the trait.
B
Because the trait was caused by a mutation, it will be passed on to offspring over many generations, resulting in a population of darker squirrels.
C
If the trait is unfavorable, it will be passed on to offspring over many generations, resulting in a population of darker squirrels.
D
If the trait is favorable, it will be passed on to offspring over many generations, resulting in a population of darker squirrels.

Did you find these answers helpful?

More from this Course

Quiz
10 verified answers

Natural Selection

Quiz
5 verified answers

Quiz

Quiz
1 verified answers

Natural Selection