Summary Year 10 Curriculum Biology End Topic Revision

Biology End Topic Revision
Mutations
Mutation:
- permanent change in DNA
- can occur by chance OR by damage to a strand in DNA
- creates variation in a species
- can be
o Neutral – no effect
o Beneficial – positive effect
o Deleterious – negative effect

Mutagen:
- the thing (agent) that causes the change in the DNA.
o e.g. radiation, chemicals, x-rays


What can cause them and what happens to the
individual?
errors in DNA replication or from the damaging effects of mutagens, such
as chemicals and radiation, which react with DNA and change the
structures of individual nucleotides.



The Theory of Evolution & Evolution by
Natural Selection
What is Evolution?
Organisms stem from a common ancestor and are hence related.


Variation
Importance of Biodiversity and variation amongst
individuals
If a trait is advantageous and helps the individual survive and reproduce,
the genetic variation is more likely to be passed to the next generation.

Factors that affect phenotype
environment
Environmental factors such as diet, temperature, oxygen levels, humidity,
light cycles, and the presence of mutagens can all impact which of an