Evolution - Natural Selection and Mutation Flashcards
Natural selection explains how ____ occurs
Natural selection explains how EVOLUTION occurs
Who came up wit the idea of natural selection?
Charles Darwin
Individuals within a species show ____ because of the differences in their ____ .
Individuals with characteristics that make them ____ ____ to the environment have a ____ ____ of ____ and so are more likely to ____ ____ .
Therefore the ____ that are responsible for the ____ ____ are more likely to be ____ ____ to the ____ ____ .
Individuals within a species show VARIATION because of the differences in their GENES .
Individuals with characteristics that make them BETTER ADAPTED to the environment have a BETTER CHANCE of SURVIVAL and so are more likely to BREED SUCCESSFULLY .
Therefore the GENES that are responsible for the USEFUL CHARACTERISTICS are more likely to be PASSED ON to the NEXT GENERATION .
Individuals within a species show ____ because of the differences in their ____ .
Individuals within a species show VARIATION because of the differences in their GENES .
Individuals with characteristics that make them ____ ____ to the environment have a ____ ____ of ____ and so are more likely to ____ ____ .
Individuals with characteristics that make them BETTER ADAPTED to the environment have a BETTER CHANCE of SURVIVAL and so are more likely to BREED SUCCESSFULLY .
Therefore the ____ that are responsible for the ____ ____ are more likely to be ____ ____ to the ____ ____ .
Therefore the GENES that are responsible for the USEFUL CHARACTERISTICS are more likely to be PASSED ON to the NEXT GENERATION .
What are the 2 things that can cause genetic differences (variation)?
- Sexual reproduction
2. Mutations
What is a mutation?
A change in an organism’s DNA
Are most mutations useful?
NO - most of the time they have no effect
and sometimes they can be disadvantageous
What makes a mutation beneficial?
If it produces a useful characteristic
Why might the characteristic caused by mutation be beneficial?
Gives the organism a better chance of SURVIVING and REPRODUCING
What happens if the organism has a better chance of surviving and reproducing (because of the beneficial mutation)?
The beneficial mutation is more likely to be passed on to FUTURE GENERATIONS by NATURAL SELECTION
What will happen over time to a beneficial mutation?
It will ACCUMULATE in a population
e.g. how some strains of bacteria have become resistant to antibiotics due to mutation
