Chapter 8

Question 1

allele

Answer 1

different forms of genes (such as round or wrinkled in seeds). each chromosome has one of these. we have 2 copies of every chromosomes so we have 2 of these for each gene. one from mom and one from dad

Question 1

dominant

Answer 1

trait that appears in F1, Rr - big R

Question 1

Mendel’s 1st law. two copies of a gene separate when an individual makes gametes. during meiosis, each gamete receives only one copy of each gene.

Answer 1

law of segregation

Question 1

crossing parental varieties with one trait that is different crossing two homozygous parents on one trait to get a heterozygous F1. this is a 2x2 Punnett square

Answer 1

monohybrids

Question 1

do this to find out if the what the genotype of an organism is. cross unkown F1 with a known homozygous recessive (rr) because it doesn’t mask the phenotype

Answer 1

test cross

Question 2

recombinant

Answer 2

offspring that look part paternal and part maternal, this means there was a crossing over event

Question 3

males (XY) are this, only one copy of the X chromosome

Answer 3

hemizygous

Question 5

Expressivity

Answer 5

a parameter that describes the effects of the environment on the genotype. the degree to which genotype is expressed in an individual

Question 6

we only get mitochondrial or chloroplast DNA (organelles) from the mom

Answer 6

maternal or cytoplasmic inheritance

Question 7

locus, loci (pl.)

Answer 7

where a gene is located in a chromosome

Question 7

epistasis

Answer 7

the phenotypic expression of one gene is influenced by another gene

Question 8

two copies of the homozygous allele (either dominant or recessive), it can only pass on 1 trait

Answer 8

true-breeding individual

Question 9

2 copies of the same allele. RR, rr

Answer 9

homozygous

Question 10

offspring that look part paternal and part maternal, this means there was a crossing over event

Answer 10

recombinant

Question 11

second filial generation (F2)

Answer 11

offspring of first filial generation

Question 12

Mendel’s 2nd law. copies of different genes on different chromosomes assort independently during gamete formation

Answer 12

law of independent assortment

Question 14

how close are two genes on a chromosome? this can alter their patterns of inheritance. if they are further apart crossing over is more common, if they are closer together they are more tightly linked

Answer 14

linkage analysis

Question 15

X-linked recessive inheritance

Answer 15

phenotypes that appear much more often in males because women are XX and one X can “mask” the other X, while XY is hemizygous

Question 16

you get one copy of DNA carried on a chromosome from each parent. each chromosome remains distinct and intact (doesn’t blend). you get 2 genes for each trait, one from each parent. Mendel’s theory

Answer 16

particulate theory of inheritance

Question 16

hemizygous

Answer 16

males (XY) are this, only one copy of the X chromosome

Question 17

a parameter that describes the effects of the environment on the genotype. the proportion of individuals with a certain genotype that show the phenotype (100% in Huntington’s disease, if you have a copy you will get the disease)

Answer 17

penetrance

Question 18

monohybrids

Answer 18

crossing parental varieties with one trait that is different crossing two homozygous parents on one trait to get a heterozygous F1. this is a 2x2 Punnett square

Question 20

heterozygous

Answer 20

2 different alles, Rr

Question 20

different forms of genes (such as round or wrinkled in seeds). each chromosome has one of these. we have 2 copies of every chromosomes so we have 2 of these for each gene. one from mom and one from dad

Answer 20

allele

Question 21

this disorder is in a gene on the X chromosome (which is larger than Y and has a lot of genes). this causes X-linked recessive phenotypes

Answer 21

sex-linked inheritance

Question 23

2 different alles, Rr

Answer 23

heterozygous

Question 23

where a gene is located in a chromosome

Answer 23

locus, loci (pl.)

Question 25

penetrance

Answer 25

a parameter that describes the effects of the environment on the genotype. the proportion of individuals with a certain genotype that show the phenotype (100% in Huntington's disease, if you have a copy you will get the disease)

Question 25

allele present in the majority of the population, not mutant

Answer 25

wild-type allele

Question 26

offspring of peranetal generation

Answer 26

first filial generation (F1)

Question 28

codominance

Answer 28

two alleles of a gene produce phenotypes that are both present in a heterozygote at the same time. e.g. blood type AB has both A and B oligosaccharide sugars

Question 30

one trait disappears in F1 and reappears in F2. Rr - little r

Answer 30

recessive

Question 31

character / trait

Answer 31

observable physical feature

Question 32

phenotype

Answer 32

appearance of organism (round or wrinkled seeds)

Question 32

hybrid vigor

Answer 32

when you cross two different true-breeding homozygotes and offspring is stronger, larger, better. e.g. happens with corn

Question 34

autosomal recessive disorder / recessive inheritance

Answer 34

person has to have two bad copies (homozygous recessive) of the gene to have this. people usually have two unaffected parents. mating between relatives increases chances of producing a child with homozygous recessive disorder compared to mating with the general public because genes run through families. e.g. Sickle cell disease

Question 35

rare, stable, inherited changes in genetic material (DNA) that get passed down. can cause a change in the phenotype

Answer 35

mutation

Question 36

genetic makeup of organism (RR, Rr, rr)

Answer 36

genotype

Question 37

how close are two genes on a chromosome? this can alter their patterns of inheritance. if they are further apart crossing over is more common, if they are closer together they are more tightly linked

Answer 37

linkage analysis

Question 38

two alleles of a gene produce phenotypes that are both present in a heterozygote at the same time. e.g. blood type AB has both A and B oligosaccharide sugars

Answer 38

codominance

Question 39

dihybrid cross

Answer 39

4x4 square, looking at 2 different traits. results in 9 different genotypes and phenotypes are in a 9:3:3:1 ratio

Question 41

law of independent assortment

Answer 41

Mendel's 2nd law. copies of different genes on different chromosomes assort independently during gamete formation

Question 41

observable physical feature

Answer 41

character / trait

Question 42

genotype

Answer 42

genetic makeup of organism (RR, Rr, rr)

Question 43

person has to have two bad copies (homozygous recessive) of the gene to have this. people usually have two unaffected parents. mating between relatives increases chances of producing a child with homozygous recessive disorder compared to mating with the general public because genes run through families. e.g. Sickle cell disease

Answer 43

autosomal recessive disorder / recessive inheritance

Question 44

mutation

Answer 44

rare, stable, inherited changes in genetic material (DNA) that get passed down. can cause a change in the phenotype

Question 46

recessive

Answer 46

one trait disappears in F1 and reappears in F2. Rr - little r

Question 47

homozygous

Answer 47

2 copies of the same allele. RR, rr

Question 47

when you cross two different true-breeding homozygotes and offspring is stronger, larger, better. e.g. happens with corn

Answer 47

hybrid vigor

Question 48

pedigree

Answer 48

family tree. geneticists use these to determine if a rare disease allele is dominant or recessive. this c an determine how a disorder runs through a family and what kind of disorder it is.

Question 48

autosomal dominant disorder / dominant inheritance

Answer 48

the disease allele is dominant, everyone with the disease phenotype has an affected parent. e.g. Huntington's disease

Question 50

parental generation

Answer 50

original organisms that you cross to form F1

Question 51

sex-linked inheritance

Answer 51

this disorder is in a gene on the X chromosome (which is larger than Y and has a lot of genes). this causes X-linked recessive phenotypes

Question 53

offspring of first filial generation

Answer 53

second filial generation (F2)

Question 53

the disease allele is dominant, everyone with the disease phenotype has an affected parent. e.g. Huntington's disease

Answer 53

autosomal dominant disorder / dominant inheritance

Question 54

a parameter that describes the effects of the environment on the genotype. the degree to which genotype is expressed in an individual

Answer 54

Expressivity

Question 55

4x4 square, looking at 2 different traits. results in 9 different genotypes and phenotypes are in a 9:3:3:1 ratio

Answer 55

dihybrid cross

Question 56

maternal or cytoplasmic inheritance

Answer 56

we only get mitochondrial or chloroplast DNA (organelles) from the mom

Question 58

an heterozygote with an intermediate (blended) phenotype, the offspring has a blended phenotype of its parents

Answer 58

incomplete dominane

Question 59

law of segregation

Answer 59

Mendel's 1st law. two copies of a gene separate when an individual makes gametes. during meiosis, each gamete receives only one copy of each gene.

Question 60

quantitative traits

Answer 60

traits conferred by multiple genes. called polygenic inheritance. they can be measured, it is gradual. e.g. eye color, skin color

Question 61

test cross

Answer 61

do this to find out if the what the genotype of an organism is. cross unkown F1 with a known homozygous recessive (rr) because it doesn't mask the phenotype

Question 62

incomplete dominane

Answer 62

an heterozygote with an intermediate (blended) phenotype, the offspring has a blended phenotype of its parents

Question 63

trait that appears in F1, Rr - big R

Answer 63

dominant

Question 64

wild-type allele

Answer 64

allele present in the majority of the population, not mutant

Question 65

family tree. geneticists use these to determine if a rare disease allele is dominant or recessive. this c an determine how a disorder runs through a family and what kind of disorder it is.

Answer 65

pedigree

Question 67

true-breeding individual

Answer 67

two copies of the homozygous allele (either dominant or recessive), it can only pass on 1 trait

Question 67

phenotypes that appear much more often in males because women are XX and one X can "mask" the other X, while XY is hemizygous

Answer 67

X-linked recessive inheritance

Question 69

the phenotypic expression of one gene is influenced by another gene

Answer 69

epistasis

Question 70

original organisms that you cross to form F1

Answer 70

parental generation

Question 71

linkage analysis

Answer 71

how close are two genes on a chromosome? this can alter their patterns of inheritance. if they are further apart crossing over is more common, if they are closer together they are more tightly linked

Question 72

first filial generation (F1)

Answer 72

offspring of peranetal generation

Question 73

offspring that look part paternal and part maternal, this means there was a crossing over event

Answer 73

recombinant

Question 74

multiple alleles

Answer 74

increase the number of possible phenotypes and may show a hierarchy of dominance (rabbit example). any one individual only has two

Question 75

appearance of organism (round or wrinkled seeds)

Answer 75

phenotype

Question 76

traits conferred by multiple genes. called polygenic inheritance. they can be measured, it is gradual. e.g. eye color, skin color

Answer 76

quantitative traits

Question 77

increase the number of possible phenotypes and may show a hierarchy of dominance (rabbit example). any one individual only has two

Answer 77

multiple alleles

Question 78

particulate theory of inheritance

Answer 78

you get one copy of DNA carried on a chromosome from each parent. each chromosome remains distinct and intact (doesn't blend). you get 2 genes for each trait, one from each parent. Mendel's theory