Unit 1: Evolution - Adaptation, Variation and Mutation Flashcards
What are variations?
Structural, functional, or physiological differences between individuals
What do not all variations become?
NOT all variations become adaptations
What determines whether a variable has a positive/negative/no effect on an individuals ability to survive and reproduce?
Individuals possessing a helpful variation are more likely to survive and have a higher chance of passing this variation on to their offspring
What will happen to the variation?
It will become more frequent.
What happens when a variation becomes more frequent?
Becomes a CHARACTERISTIC or TRAIT of the population
Why do a litter of puppies or kittens do not usually all look the same?
They have inherited different parts of the DNA (called ALLELES) from their parents.
Where is this genetic information that the puppies and kittens inherit expressed?
Some of this genetic information is expressed in each kitten’s phenotype (physical appearance and behavior)
But much of it has no visible effect and remains part of each kitten’s genetic make-up and continues to be passed on to next generations
What is genetic variation?
In a population, results from the variety of genetic information in all individuals of the population
What are mutations?
Changes in the genetic material (DNA) of an organism
What are mutations the only source of?
New genetic variation when inherited
What do mutations do?
Continuously happening in DNA of all living organisms… happening to us right now!
How can mutations occur?
Spontaneously when DNA is copied
What can mutations be caused by?
Ultraviolet radiation (or other environmental agents)
What happens after a mutation?
-Cell could die
-Malfunction
-Multiply more than it should and form a tumor!
What can mutations drastically change? What can they be?
Mutations that drastically change the shape or structure of DNA can be harmful to an organism
