Middle School Life Science : Explain how natural selection leads to an increase or decrease in the expression of certain traits
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Example Questions
Example Question #11 : Natural Selection
If a species of bird adapts to have a broader and shorter wingspan, this would be an example of __________.
a structural adaptation
an inverse adaptation
a functional adaptation
a behavioral adaptation
a structural adaptation
The answer is a "structural adaptation."
Adaptations are any change in the structure or behavior of a species which helps it to become better fitted to survive and reproduce in its environment. When a random mutation occurs, it can lead to an increase in the expression of specific traits. When traits are inheritable and beneficial, they become more common because those individuals thrive. Through the process of natural selection, more individuals with beneficial mutations will survive than those without it, and it will lead to an increase in the expression of those certain traits throughout the population. On a broader scale over a longer period of time, this is how natural selection leads to evolution.
Structural adaptations are physical features of an organism like the bill on a bird or the fur on a bear. Other adaptations are behavioral. Behavioral adaptations are the things organisms do to survive. For example, bird calls and migration are behavioral adaptations.
Example Question #12 : Natural Selection
If a random mutation is favorable (meaning it helps the species survive) then what will happen to a population in which the mutation occurs?
not enough information
the specific trait will be expressed less frequently
there will be no change in the frequency of expression for the specific trait
the specific trait will be expressed more frequently
the specific trait will be expressed more frequently
The answer is "the specific trait will be expressed more frequently."
When a random mutation occurs, it can lead to an increase in the expression of specific traits. When traits are inheritable and beneficial, they become more common because those individuals thrive. Through the process of natural selection, more individuals with beneficial mutations will survive than those without it, and it will lead to an increase in the expression of those certain traits throughout the population. On a broader scale over a longer period of time, this is how natural selection leads to evolution.
Structural adaptations are physical features of an organism like the bill on a bird or the fur on a bear. Other adaptations are behavioral. Behavioral adaptations are the things organisms do to survive. For example, bird calls and migration are behavioral adaptations.
Example Question #13 : Natural Selection
Which of the following is NOT an example of a structural adaptation?
birds with rounder beaks
birds migrating in winter
birds with camouflaged feathers
birds more down feathers
birds migrating in winter
The answer is "birds migrating in winter"
When a random mutation occurs, it can lead to an increase in the expression of specific traits. When traits are inheritable and beneficial, they become more common because those individuals thrive. Through the process of natural selection, more individuals with beneficial mutations will survive than those without it, and it will lead to an increase in the expression of those certain traits throughout the population. On a broader scale over a longer period of time, this is how natural selection leads to evolution.
Structural adaptations are physical features of an organism like the bill on a bird or the fur on a bear. Other adaptations are behavioral. Behavioral adaptations are the things organisms do to survive. For example, bird calls and migration are behavioral adaptations.
Example Question #14 : Natural Selection
What could you expect about the expression of a specific trait if it is found to be harmful?
the population will not see an increase in the expression of that trait
the individual will die sooner than its counterparts
it is not an adaptation
all of these
all of these
The answer is "all of these."
When a random mutation occurs, it can lead to an increase in the expression of specific traits. When traits are inheritable and beneficial, they become more common because those individuals thrive. Through the process of natural selection, more individuals with beneficial mutations will survive than those without it, and it will lead to an increase in the expression of those certain traits throughout the population. On a broader scale over a longer period of time, this is how natural selection leads to evolution.
Structural adaptations are physical features of an organism like the bill on a bird or the fur on a bear. Other adaptations are behavioral. Behavioral adaptations are the things organisms do to survive. For example, bird calls and migration are behavioral adaptations.
Example Question #5 : Explain How Natural Selection Leads To An Increase Or Decrease In The Expression Of Certain Traits
How does the process of natural selection influence the expression of specific traits?
expression of specific traits are NOT affected by natural selection
specific traits that are favorable are expressed MORE frequently in populations
specific traits that are favorable are expressed LESS frequently in populations
specific traits that are NOT favorable are expressed MORE frequently in populations
specific traits that are favorable are expressed MORE frequently in populations
The answer is "specific traits that are favorable are expressed more frequently in populations."
When a random mutation occurs, it can lead to an increase in the expression of specific traits. When traits are inheritable and beneficial, they become more common because those individuals thrive. Through the process of natural selection, more individuals with beneficial mutations will survive than those without it, and it will lead to an increase in the expression of those certain traits throughout the population. On a broader scale over a longer period of time, this is how natural selection leads to evolution.
Structural adaptations are physical features of an organism like the bill on a bird or the fur on a bear. Other adaptations are behavioral. Behavioral adaptations are the things organisms do to survive. For example, bird calls and migration are behavioral adaptations.
Example Question #15 : Natural Selection
After many thousands of years of tectonic activity, an island splits apart and separates into two smaller islands. In the process, two populations of the same lizard species become separated and eventually, they cannot interbreed. One population even developed a slightly darker coloration. What was the result of natural selection during this extended period of time?
extinction
speciation
decreased genetic diversity
a decrease in offspring viability
speciation
The answer is "speciation."
When a random mutation occurs, it can lead to an increase in the expression of specific traits. When traits are inheritable and beneficial, they become more common because those individuals thrive. Through the process of natural selection, more individuals with beneficial mutations will survive than those without it, and it will lead to an increase in the expression of those certain traits throughout the population. On a broader scale over a longer period of time, this is how natural selection leads to speciation and eventually evolution.
Structural adaptations are physical features of an organism like the bill on a bird or the fur on a bear. Other adaptations are behavioral. Behavioral adaptations are the things organisms do to survive. For example, bird calls and migration are behavioral adaptations.
Example Question #6 : Explain How Natural Selection Leads To An Increase Or Decrease In The Expression Of Certain Traits
Which example from the fossil record best represents that natural selection has been occurring over millions of years?
Fossils in the oldest layers of rock are more complex than in younger layers of rock.
It is possible to find older fossils the deeper you dig in layers of rock.
It is possible to find fossils of animals that no longer exist because they are ancestors of current species.
Fossils of current species have been found in layers of rock that are hundreds of millions of years old.
It is possible to find fossils of animals that no longer exist because they are ancestors of current species.
The answer is "It is possible to find fossils of animals that no longer exist because they are ancestors of current species."
When a random mutation occurs, it can lead to an increase in the expression of specific traits. When traits are inheritable and beneficial, they become more common because those individuals thrive. Through the process of natural selection, more individuals with beneficial mutations will survive than those without it, and it will lead to an increase in the expression of those certain traits throughout the population. On a broader scale over a longer period of time, this is how natural selection leads to speciation and eventually evolution.
Structural adaptations are physical features of an organism like the bill on a bird or the fur on a bear. Other adaptations are behavioral. Behavioral adaptations are the things organisms do to survive. For example, bird calls and migration are behavioral adaptations.
Example Question #7 : Explain How Natural Selection Leads To An Increase Or Decrease In The Expression Of Certain Traits
A random mutation occurs in a tree frog population. The tree frog has a new set of alleles that cause it to develop more lightly colored camouflage than its counterparts. Which of the following will determine whether this lightly colored camouflage will be expressed more frequently in the population?
natural selection
none of these
whether the lightly colored camouflage is beneficial to survival
all of these
whether the trait is heritable
all of these
The answer is, "all of these."
When a random mutation occurs, it can lead to an increase in the expression of specific traits. When traits are inheritable and beneficial, they become more common because those individuals thrive. Through the process of natural selection, more individuals with beneficial mutations will survive than those without it, and it will lead to an increase in the expression of those certain traits throughout the population. On a broader scale over a longer period of time, this is how natural selection leads to speciation and eventually evolution.
Structural adaptations are physical features of an organism like the bill on a bird or the fur on a bear. Other adaptations are behavioral. Behavioral adaptations are the things organisms do to survive. For example, bird calls and migration are behavioral adaptations.
Example Question #16 : Natural Selection
Which of the following explains why natural selection acts on an organism's phenotype and not its genotype?
Phenotypes can be inherited by offspring.
Phenotypes influence the way organisms survive in their environment.
Genotypes don't change as offspring are born.
Genotypes change in response to environments.
Phenotypes influence the way organisms survive in their environment.
The answer is "Phenotypes influence the way organisms survive in their environments."
When a random mutation occurs, it can lead to an increase in the expression of specific traits. When traits are inheritable and beneficial, they become more common because those individuals thrive. Through the process of natural selection, more individuals with beneficial mutations will survive than those without it, and it will lead to an increase in the expression of those certain traits throughout the population. On a broader scale over a longer period of time, this is how natural selection leads to speciation and eventually evolution.
Structural adaptations are physical features of an organism like the bill on a bird or the fur on a bear. Other adaptations are behavioral. Behavioral adaptations are the things organisms do to survive. For example, bird calls and migration are behavioral adaptations.
Example Question #9 : Explain How Natural Selection Leads To An Increase Or Decrease In The Expression Of Certain Traits
Which of the following best illustrates natural selection?
An organism with favorable genetic variation will survive and breed.
Competition between two species will continue until one of them "loses" resources.
The breeding opportunities in a population always go to the largest and strongest individuals.
Individual organisms develop resistance to genetic variation over time.
An organism with favorable genetic variation will survive and breed.
The answer is "An organism with favorable genetic variation will survive and breed." Even though "The breeding opportunities in a population always go to the largest and strongest individuals." sounds like it could be true - the strongest and largest physical traits are not always the most advantageous for survival. Consider that some species require camouflage or being small for hiding from predators.
When a random mutation occurs, it can lead to an increase in the expression of specific traits. When traits are inheritable and beneficial, they become more common because those individuals thrive. Through the process of natural selection, more individuals with beneficial mutations will survive than those without it, and it will lead to an increase in the expression of those certain traits throughout the population. On a broader scale over a longer period of time, this is how natural selection leads to speciation and eventually evolution.
Structural adaptations are physical features of an organism like the bill on a bird or the fur on a bear. Other adaptations are behavioral. Behavioral adaptations are the things organisms do to survive. For example, bird calls and migration are behavioral adaptations.
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