Bio 9 - Genetic Diversity

Question 1

What is a mutation?

Answer 1

Any change to the quantity to the base sequence of the DNA of an organism

Question 2

What is a gene mutation?

Answer 2

Any change to one or more nucleotide bases, or change in the sequence of the bases, in DNA

Question 3

What is substitution of bases?

Answer 3

The type of gene mutation in which a nucleotide in a DNA molecule is replaced by another nucleotide that has a different base

Question 4

What is deletion of bases?

Answer 4

When a nucleotide is lost from the normal DNA sequence.

Question 5

Why might a polypeptide not work if there is a deletion of bases?

Answer 5

The amino acid sequence of the polypeptide is entirely different so its likely not to function. Sequence of bases is read in triplets and one delayed nucleotide cases all triplet to shift to the left so they are all ready differently

Question 6

What is a chromosome mutation?

Answer 6

Changes in the structure or number of whole chromosomes

Question 7

What are the two forms of chromosome mutation?

Answer 7

• Changes in whole sets of chromosomes

- Changes in the number of individual chromosomes

Question 8

What is a diploid number?

Answer 8

Cells in which the nucleus contains two sets of chromosomes

Question 9

What is a haploid number?

Answer 9

Cells that contains only a single copy of each chromosome eg. gametes

Question 10

What is crossing over?

Answer 10

Chromatids twist around each other and bits of chromatids swap over

Question 11

When does crossing over happen?

Answer 11

During meiosis I

Question 12

What are the two events that happen in meiosis that lead to genetic variation?

Answer 12

• Crossing over

- Independant segregation

Question 13

What is independent segregation?

Answer 13

When homologous pairs are separated in meiosis I, its random which chromosome pairs up with daughter cells.
The 4 daughter cells produced have different combinations of maternal and paternal.

Question 14

Mitosis or Meiosis: Produces cells with the same number of chromosomes as the parent cell

Answer 14

Mitosis

Question 15

Mitosis or Meiosis: Produces cells with half the number of chromosomes as the parent cell

Answer 15

Meiosis

Question 16

Mitosis or Meiosis: Daughter cells are genetically identical to each other and to the parent cell

Answer 16

Mitosis

Question 17

Mitosis or Meiosis: Daughter cells are genetically different from one another and the parent cell

Answer 17

Meiosis

Question 18

Mitosis or Meiosis: Produces two daughter cells

Answer 18

Mitosis

Question 19

Mitosis or Meiosis: Produces four daughter cells

Answer 19

Meiosis

Question 20

What is genetic diversity?

Answer 20

The number of different alleles of genes in a species or population

Question 21

What is genetic diversity increased by?

Answer 21

• Mutations in the DNA
• Different alleles being introduced into a population when individual from another population migrate into them and reproduce

Question 22

What do genetic bottlenecks do to genetic diversity?

Answer 22

Reduce it

Question 23

What is a genetic bottleneck?

Answer 23

An event that causes a big reduction in a population

Question 24

What is the founder effect?

Answer 24

It describes what happens when a few organisms from a population start a new colony. There are only a small number of different alleles in the initial gene pool.