genetics

Question 1

phenotype

Answer 1

the gens that are expressed physically

Question 2

evolution

Answer 2

the change in allele frequency of a population overtime

Question 3

gene pool

Answer 3

the total number of alleles with a population

Question 4

multiple alleles

Answer 4

Multiple alleles occur with genes that have more than two different alleles, through an individual will only have two of the alleles in its genotype.

Question 5

bottleneck effect

Answer 5

when populations decrease in numbers due to catastrophic event or human action

Question 6

lethal alleles

Answer 6

A lethal allele occurs when a mutation results in an allele that produces a non-functional version of an essential protein. This results in the organism dying.

Question 7

genotype

Answer 7

genetic make-up of an individual

Question 8

haploid

Answer 8

one set of chromosomes

Question 9

genetic drift

Answer 9

loss or change in the frequency of an allele in a small population due to chance alone

Question 10

dominant

Answer 10

An allele that if present is always expressed phenotypically

Question 11

founder effect

Answer 11

when a small group of a population colonize an isolated area, changing allele frequency.

Question 12

trait

Answer 12

genetic feature

Question 13

co-dominance

Answer 13

Co-dominance inheritance occurs when both alleles are equally dominant and both alleles are present in the heterozygous genotype they are both expressed in the phenotype

Question 14

incomplete dominance

Answer 14

Incomplete dominance in heritance occurs when neither allele ‘dominates’ the other and both alleles are present in the heterozygous genotype, they produce a blended phenotype.

Question 15

independent assortment

Answer 15

each pair of homologous chromosomes are sorted independently of the other pairs during meiosis which greatly increases genetic variation

Question 16

homozygous

Answer 16

having the same alleles

Question 17

test cross

Answer 17

mating involving an unknown genotype with the homozygous recessive

Question 18

diploid

Answer 18

two sets of chromosomes

Question 19

heterozygous

Answer 19

having different forms of an allele

Question 20

chiasmata

Answer 20

the points on chromatids where the homologous chromosomes cross

Question 21

chromosome segregation

Answer 21

the separation of alleles during meiosis so that each gamete carries only one allele

Question 22

zygote

Answer 22

a diploid cell formed by the fusion of two haploid cells

Question 23

meiosis

Answer 23

cell division that produces sex cells- haploid from diploid

Question 24

natural selection

Answer 24

the selection of individuals based on their fitness to survive and then breed

Question 25

alleles

Answer 25

an alternative form of a gene

Question 26

centromere

Answer 26

responsible for the separation of chromosomes

Question 27

recombinant

Answer 27

the gametes produced as a result of crossing over

Question 28

chromatids

Answer 28

the two strands of a replicated chromosome

Question 29

crossing over

Answer 29

the exchange of genetic codes between homologous chromosomes during meiosis

Question 30

gametes

Answer 30

sex cells (sperm and eggs)

Question 31

somatic cell

Answer 31

all body cells minus sex cells

Question 32

inheritance

Answer 32

when genetic information is passed down from one generation to the next

Question 33

recessive

Answer 33

if present the gene is only expressed phenotypically when homozygous

Question 34

homologous pair

Answer 34

pairs of chromosomes having the same genes

Question 35

chromosomes

Answer 35

thread like structure within a cell nucleus made of DNA that contains genes

Question 36

mutation

Answer 36

alternation of the sequence of bases on the DNA. This produces new genetic information and maybe new phenotypes

Question 37

DNA

Answer 37

makes up chromosomes and codes for proteins. Double helix like structure

Question 38

gene

Answer 38

a sequence of DNA that codes for a specific protein or RNA molecule

Question 39

mutagen

Answer 39

an agent that causes change in DNA, such as chemicals or radiation

Question 40

genetic variation

Answer 40

the differences in the DNA sequence between individuals of the same species

Question 41

fertilization

Answer 41

the fusion of gametes to create life