Gene pools and mutations

What is a gene pool?

• Sum total of genes (genotypes), with all their variations, possessed by particular species at particular time (in population).

What 4 factors cause changes in gene pools?

1. Natural selection

2. Mutations

3. Founder effect

4. Random genetic drift

What are 8 factors contributing to allele frequency and evolution?

1. Mutation

2. Variation

3. Natural selection

4. Barriers to gene flow (isolation)

5. Random genetic drift

6. Migration & founder effect

7. Speciation

8. Genetic diseases

What is a mutation?

• Permanent structural alteration in organism's DNA.

What are 4 types of mutations?

1. Gene or point mutations

2. Chromosomal mutations

3. Somatic mutations

4. Germinal or germline mutations

What are gene or point mutations?

• Changes in base sequence of single gene.

What are chromosomal mutations?

• All or part of chromosome is affected

What are somatic mutations?

• Occur in normal body cells (after organism has developed) and are not passed onto offspring.

What are germinal or germline mutations?

• Occur in gametes or were present when individual was fertilised and are passed onto offspring.

What are 5 types of gene or point mutations?

1. Missense substitution mutation

2. Silent substitution mutation

3. Nonsense substitution mutation

4. Insertion

5. Deletion

What is a missense substitution mutation?

• If substitution changes amino acid.

What is a silent substitution mutation?

• If substitution does not change amino acid.

What is a nonsense substitution mutation?

•  If substitution changes amino acid to "STOP".

What is a insertion frameshift mutation?

• Nitrogen base added to sequence.

What is a deletion frameshift mutation?

• Nitrogen base removed from sequence.

What are 5 types of chromosomal mutations?

1. Deletion

2. Duplication

3. Inversion

4. Insertion

5. Translocation

What is a deletion chromosomal mutation?

• Section of genetic material is lost.

What is a duplication chromosomal mutation?

• Portion of chromosome is copied and replicated.

What is a inversion chromosomal mutation?

• Segment of chromosome is reversed and may disrupt pairing of homologous chromosomes during meiosis.

What is a insertion chromosomal mutation?

• Section of one chromosome is broken off and added to another chromosome.

What is a translocation chromosomal mutation?

• Piece of 2 chromosomes breaks off and transferred to other chromosome.

What are 3 examples of human mutations?

1. Locomotion

2. Erect stance

3. Jaw shape

What are 3 causes of mutations?

1. DNA replication

2. Cell division

3. Mutagens

What is DNA replication?

• When new strands of DNA is made.