Vocabulary
What is Natural Selection?
A process in which individuals that have certain inherited traits tend to survive and reproduce better than other individuals because of those traits.
What is the first step of Natural Selection?
Overproduction.
Does a population or individual evolve?
Populations evolve.
What is variation?
Any difference between individuals of the same species.
What is Adaptation?
Inherited characteristics that increases an organisms chance of survival.
What are Species?
A group of similar organisms that can breed and produce fertile offspring.
What is the second step of Natural Selection?
Variation.
What are the three types of Natural Selection?
Direction, Stabilizing, and Disruptive Selection.
What are the 2 main sources that causes Variation?
1. Mixing of DNA through cell division + fertilization.
2.Through new mutations (changes in DNA).
What causes Adaptation?
A gene mutates or changes by accident.
What is Competition?
The struggle between organisms to survive in a habitat with limited resources.
What is the third step of Natural Selection?
Adaptation.
What is Directional Selection?
Occurs when Natural Selection favors one of the extreme variations of a trait.
What type of differences in DNA of organisms come from 2 main sources?
Inherited differences.
When is an organism no longer well adapted?
When there are changes in the environment.
What are Mutations?
Changes in the genetic material that leads to different traits.
What is the last step of Natural Selection?
Descent with modification.
What is Stabilizing Selection?
Form of Natural Selection in which individuals near the center, of a distribution curve have higher fitness than individuals at either end of the curve.
Why is genetic variation important?
Enables some organisms to survive better than others in the environment in which they live.
Over many generations, what would the number of well-adapted organisms in a population be expected to do?
Increase until it becomes a general attribute of the species.
What is Descent with Modification?
Principle that each living species has descended, with changes, from other species over time.
What is Natural Selection? (Using you own words)
The environment selects traits that help an individual survive and reproduce -> Causes populations to change over time.
What is a Disruptive Selection?
Type of Natural Selection that favors individuals at both extremes of the phenotypic range.
How do mutations lead to genetic variation?
Mutation creates slightly different versions of the same genes, called alleles.
What is a physiological adaptation?
An internal change that animals and plants go through to ensure their survival in their environment.