Genetics and Variation - Genetic diversity and adaptation: Key Terms

Question 1

Mutation

Answer 1

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

Question 2

Gene mutation

Answer 2

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

Question 3

Chromosome mutation

Answer 3

Changes in the structure or number of whole chromosomes

Question 4

Non-disjunction

Answer 4

When individual homologous pairs fail to separate during meiosis

Question 5

Meiosis

Answer 5

The division of a cell that produces four daughter cells, each with half the number of chromosomes as the parent cell

Question 6

Independent segregation

Answer 6

The random lining up of the pairs of chromosomes, the combination of chromosomes in a random order, a matter of chance

Question 7

Crossing over

Answer 7

When the chromatids cross over one another many times

Question 8

Recombination

Answer 8

When broken-off portions of chromatid recombine with another chromatid

Question 9

Species

Answer 9

A group of similar organisms that can breed together to produce fertile offspring

Question 10

Genetic diversity

Answer 10

The total number of different alleles in a population

Question 11

Allele frequecny

Answer 11

The relative frequency of an allele at a particular locus in a population

Question 12

Gene pool

Answer 12

The total number of alleles in a particular population at a specific time

Question 13

Directional selection

Answer 13

Selection may favour individuals that vary from the mean of the population

Question 14

Stabilising selection

Answer 14

Selection may favour average individuals, preserving characteristics of the population

Question 15

Anatomical

Answer 15

Characteristics relating to bodily structure

Question 16

Physiological

Answer 16

Characteristics relating with the functions and activities of living organisms

Question 17

Behavioural

Answer 17

Characteristics relating to organisms behaviour