inheritance topic 7

Question 1

Abiotic factors

Answer 1

non-living factors of ecosystem

Question 2

Biotic factors

Answer 2

living factors of ecosystem

Question 3

allele

Answer 3

version of a gene

Question 4

allele frequency

Answer 4

number of times an alleles in a population’s gene pool

Question 5

allopatric speciation

Answer 5

speciation that occurs when two populations become geographically isolated

Question 6

Autosomal linkage

Answer 6

two or more genes are on the same autosomal chromosome.

they are unlikely to be separated by crossing over during meiosis so are often inherited together

Autosome - a chromosome that is not a sex chromosome ( X or Y chromosome)

Question 7

Belt transect

Answer 7

• determine the abundance + distributions of organisms in an ecosystem

Question 8

biodiversity

Answer 8

variety of genes, species and habitats within a particular area

Question 9

carrying capacity

Answer 9

the average size of a population that can be supported by an ecosystem over extended period of time.

this varies depending on biotic and abiotic factors

Question 10

chi squared test

Answer 10

determines whether a pattern of inheritance is statistically significant

Question 11

codominant

Answer 11

when both alleles in a heterozygous organism contribute equally to the gene pool

Question 12

climax community

Answer 12

stable community that exists at the final stage of ecological succession

Question 13

conservation

Answer 13

humans maintaining ecosystems and biodiversity to preserve earth’s resources
- involves MANAGEMENT OF SUCCESSION

Question 14

degrees of freedom ( chi squared test )

Answer 14

the number of categories minus one

Question 15

dihybrid inheritance

Answer 15

inheritance of two different genes, that determine two phenotypes, or two different chromosomes

Question 16

directional selection

Answer 16

favours the extreme phenotype

Question 17

disruptive selection

Answer 17

favours individuals with extreme phenotypes, selects against those with phenotypes close to mean

Question 18

epistasis

Answer 18

arises when the alleles of one genes masks the expression of another in the phenotype

Question 19

dominant epistasis

Answer 19

dominant allele at one gene locus masks the expression of alleles at second gene locus
ratio 12:3:1, 13:3

Question 20

recessive epistasis

Answer 20

recessive allele at one locus completely masks expression of another allele at a second locus
ratio 9:3:4

Question 21

evolution

Answer 21

gradual change in allele frequency with population over time
occurs because of natural selection

Question 22

gene

Answer 22

A length of DNA on a chromosome that codes for the production of one or more
polypeptide chains and functional RNA

Question 23

gene pool

Answer 23

all alleles in individuals that make up a population

Question 24

genetic drift

Answer 24

variation in allele frequencies in small populations due to chance

Question 25

genetic variation

Answer 25

Differences in genotypes between members of a population which may
occur due to mutations, meiosis, or random fertilisation.
( independent segregation, crossing over )

Question 26

sex linkage

Answer 26

the expression of an allele is dependent on the gender of the individual as gene is located on the sex chromosomes

Question 27

monohybrid inheritance

Answer 27

phenotype controlled by a single gene

Question 28

speciation

Answer 28

The formation of new species due to the evolution of two reproductively
separated populations. Two forms: allopatric and sympatric speciation.

Question 29

stabilising selection

Answer 29

favours phenotype closest to mean (average)

Question 30

sympatric speciation

Answer 30

A form of speciation that occurs when two populations within the
same area become reproductively isolated

Question 31

variation

Answer 31

The differences between individuals due to genes, the environment or a
combination of both.