The Gene Pool

Question 1

Allele

Answer 1

An alternative form of a gene

Question 2

Population

Answer 2

All the members of a species in a location at a time

Question 3

Gene pool

Answer 3

The complete set of alleles within a particular population

Question 4

Gene pool

Answer 4

The complete set of alleles within a particular population

Question 5

Allele frequency

Answer 5

The proportion of a certain allele in a gene pool

Question 6

Genetic diversity

Answer 6

The variation in genetic makeup or alleles within a population

Question 7

Mutation

Answer 7

Any change to the DNA of an organism that is unpredictable and random

Question 8

Do most mutations have an effect on the organism?

Answer 8

No, but some mutations result in a phenotypic change

Question 9

Two types of mutations

Answer 9

Spontaneous or induced

Question 10

Spontaneous mutation

Answer 10

A mutation that happens for no particular reason (e.g DNA copying error)

Question 11

Induced mutation

Answer 11

A mutation caused by radiation or chemical mutagen

Question 12

Mutagen

Answer 12

An agent that can cause mutations in DNA

Question 13

Where can mutations be inherited and located?

Answer 13

In the germline or somatic cells

Question 14

Germline cells

Answer 14

Mutations here are heritable. These cells are involved in production of gametes (reproductive cells)

Question 15

Somatic cells

Answer 15

not heritable - these cells don’t divide (muscle cells)

Question 16

Point mutation definition and types

Answer 16

Point mutation is when one nucleotide is altered. Types include silent, missense, nonsense, frameshift

Question 17

Silent mutation

Answer 17

A nucleotide is substituted for another, changing the codon, but still coding for the same amino acid. (doesn’t change the protein structure)

Question 18

Missense mutation

Answer 18

A nucleotide is substituted for another, changing the codon AND coding for a different amino acid. (affects protein structure)

Question 19

Nonsense mutation

Answer 19

A nucleotide is substituted for another, changing the codon for a STOP codon - stopping transcription. (affects protein structure and shortens polypeptide so it can’t function as intended)

Question 20

Frameshift mutation

Answer 20

Addition or deletion of a nucleotide, altering the reading frame of all the following nucleotides. (causes major disruption to structure+function of proteins)

Question 21

Block mutations definition and its types

Answer 21

Block mutations affect a large chunk of DNA or an entire gene, they alter the structure of a chromosome and usually occur during meiosis. Include deletion, duplication, inversion, translocation.

Question 22

Deletion mutation

Answer 22

A section of DNA is removed from the chromosome, shortening the DNA

Question 23

Duplication mutation

Answer 23

When a section of DNA is replicated, lengthening it

Question 24

Inversion mutation

Answer 24

When a section of DNA has its sequence reversed

Question 25

Translocation mutation

Answer 25

When two sections of DNA on different chromosomes switch places

Question 26

Two types of chromosomal abnormalities

Answer 26

Polyploidy and aneuploidy

Question 27

Polyploidy

Answer 27

Additional SETS of chromosomes - common in plants

Question 28

Effects of polyploidy in plants

Answer 28

Increased size, reduction in fertility, change in growth pattern

Question 29

Aneuploidy

Answer 29

Varies from the usual number of chromosomes in the genome by addition or loss of a chromosome. Monosomy is one less chromosome, trisomy is one additional

Question 30

Environmental selection pressure

Answer 30

A factor in the environment that impacts the ability of an organism to survive and reproduce

Question 31

Natural selection

Answer 31

A mechanism through which organisms that are better adapted to their environment have an increased chance of surviving and passing on their alleles

Question 32

Darwin’s observations

Answer 32

1. There is phenotypic variation 2. Offspring tend to inherit the traits of their parents 3. The species produce more offspring than required to replace themselves 4. There is a struggle to survive

Question 33

Selecting agent

Answer 33

The element of the environment that applies a selection pressure

Question 34

Sexual selection

Answer 34

A form of natural selection in which the selection pressure is the ability to obtain a mate

Question 35

Genetic drift and it’s types

Answer 35

A random event that dramatically alters a populations gene pool - only has a significant impact on a small population. E.g founder effect or bottleneck effect

Question 36

Founder effect

Answer 36

Formation of a new population by a non representative sample of individuals from parent population

Question 37

Bottleneck effect

Answer 37

The reduction in genetic diversity when a large proportion of a population is removed due to a chance event

Question 38

Inbreeding

Answer 38

Sexual reproduction between 2 related individuals

Question 39

Lower adaptive potential

Answer 39

Populations become vulnerable to new selection pressures that could challenge and wipe out the entire population due to absence of advantageous alleles

Question 40

Interbreeding

Answer 40

When two individuals living in different populations mate and have offspring

Question 41

Difference between inbreeding and interbreeding

Answer 41

Inbreeding lowers genetic diversity, increasing the chance of genetic disorders as it involves closely related species mating. Interbreeding introduces new alleles to a population’s gene pool as it involves mating between individuals of different species/populations

Question 42

Gene flow

Answer 42

The flow of alleles between populations as a result of migration or interbreeding between two populations

Question 43

Immigration

Answer 43

The entering of alleles into a population

Question 44

Emigration

Answer 44

The leaving of alleles out of a population

Question 45

What increases genetic diversity?

Answer 45

Interbreeding, immigration, mutations

Question 46

What decreases genetic diversity?

Answer 46

Natural selection, sexual selection, founder effect, bottleneck effect, emigration