Chapter 5

Question 1

A genotype that causes death

Answer 1

lethal

Question 2

causes death before the individual can reproduce

Answer 2

lethal genotype

Question 3

t/f lethal genotypes prevents passage of genes to the next gen

Answer 3

t

Question 4

t/f early-acting lethal alleles causes spontaneous abortion

Answer 4

t

Question 5

t/f a double dose of dominant allele (lethal) cancels the mutation

Answer 5

f

Question 6

t/f an indiv has two alleles for any autosomal gene

Answer 6

t

Question 7

t/f genes cannot have multiple alleles bcz its sequence can deviate in many ways

Answer 7

f

Question 8

t/f multiple alleles are considered carrier testing for cystic fibrosis

Answer 8

t

Question 9

one allele is expressed, while the other is not

Answer 9

complete dominance

Question 10

heterozygous phenotype is between those of the two homozygotes

Answer 10

incomplete dominance

Question 11

different alleles that are both expressed in a heterozygote

Answer 11

codominance

Question 12

alkaptonuria - inability to breakdown ___

Answer 12

tyrosine

Question 13

phenylketonuria - inability to breakdown ____

Answer 13

phenylalanine

Question 14

t/f the three general phenomena that seen to be exceptions to Mendel’s law, but are really not: gene expression, mitochondrial inheritance, linkage

Answer 14

t

Question 15

what type of alleles cause spontaneous abortion

Answer 15

early-acting lethal alleles

Question 16

t/f ABO gene encodes a cell surface protein while ABO blood group is based on the expression of codominant alleles

Answer 16

T

Question 17

it is determined by the patterns of molecules on the surfaces of red blood cells - these molecules are embedded in the plasma membrane with attached sugars that extend from the cell surface

Answer 17

blood type

Question 18

a phenomenon where one gene affects the expression of a second gene; the interaction between different genes, not between the alleles of the same gene

Answer 18

epistasis

Question 19

a gene that affects the expression of another gene

Answer 19

modifier gene

Question 20

In epistasis, the blocked gene is expressed normally, but the product of the modifier gene (activates or inactivates) it, removes a structure needed for it to contribute to the phenotype, or otherwise
counteracts its effects.

Answer 20

inactivates

Question 21

refers to all-or-none expression of a genotype

Answer 21

penetrance

Question 22

refers to the severity or extent

Answer 22

expressivity

Question 23

Genotype is (incompletely or completely) penetrant if some individuals do not express the phenotype

Answer 23

incompletely

Question 24

Phenotype is variably (expressive or inexpressive) if symptoms
vary in intensity among different people

Answer 24

expressive

Question 25

An allele combination that produces a phenotype in everyone who inherits it is (completely or incompletely) penetrant

Answer 25

completely

Question 26

A genotype is (completely or incompletely) penetrant if some individuals do not express the phenotype.

Answer 26

incompletely

Question 27

A single-gene disorder with many symptoms, or a gene that controls several functions or has more than one effect

Answer 27

pleiotropy

Question 28

a part of heme that is routed into the urine instead of being broken down and metabolized in cells

Answer 28

porphyrin ring

Question 29

a disease that results from deficiencies of any of several enzymes required to make heme

Answer 29

porphyrias

Question 30

y/n Is Marfan syndrome pleiotropic?

Answer 30

y

Question 31

when different genes produce the same phenotype

Answer 31

genetic heterogeneity

Question 32

Genetic heterogeneity can occur when genes encode enzymes that (inhibit or catalyze) the same biochemical pathway, or different proteins that are part of the pathway

Answer 32

catalyze

Question 33

An environmentally caused trait that appears to be inherited

Answer 33

phenocopy

Question 34

revealed that complications to mendelian inheritance are more common than originally thought

Answer 34

human genome sequence

Question 34

revealed that complications to mendelian inheritance are more common than originally thought

Answer 34

human genome sequence

Question 35

t/f mitochondrion's mtDNA have 36 genes without noncoding sequences

Answer 35

f

Question 36

t/f mitochondrion mutation rate is greater than nuclear dna

Answer 36

t

Question 37

t/f mitochondrial genes can be transmitted from mother and father to all of their offspring

Answer 37

f

Question 38

t/f mitochondrial genes encode RNA molecules and proteins

Answer 38

t

Question 39

how many mitochondrial genes encode proteins that function in cellular respiration

Answer 39

13

Question 40

the process that uses energy from digested nutrients to synthesize ATP

Answer 40

cellular respiration

Question 41

several mitochondrial disorders result from mutations in ______

Answer 41

mtDNA

Question 42

a mutation in a mitochondrial gene that encodes a tRNA or rRNA impairs the organelle's ability to manufacture ______

Answer 42

proteins

Question 43

this technique enable woman to avoid transmitting a mitochondrial disorder

Answer 43

ooplasmic transfer

Question 44

condition where the mtDNA sequence is not the same in all copies of the genome

Answer 44

heteroplasmy

Question 45

provides a powerful forensic tool to link suspects to crimes, identify war dead, and support or challenge historical records

Answer 45

mtDNA

Question 46

these genes are maternally inherited and mutate rapidly

Answer 46

mitochondrial genes

Question 47

in this disorder, cells contain mitochondria that have different alleles of a gene

Answer 47

heteroplasmy

Question 48

genes that are close on the same chromosome are said to be_____

Answer 48

linked

Question 49

refers to the transmission of genes on the same chromosome

Answer 49

linkage

Question 50

linked genes (do or do not) assort independently

Answer 50

do not

Question 51

linked genes (do or do not) produce mendelian ratios for crosses tracking two o more genes

Answer 51

do not

Question 52

an exchange between homologs that mixes up maternal and paternal gene combinations without disturbing the sequence of genes on the chromosome

Answer 52

crossing over

Question 53

chromosomes recombine during crossing-over in ________ of meiosis

Answer 53

prophase I

Question 54

______ chromosomes have the original configuration while the ________ chromosomes have new combination of alleles

Answer 54

parental, recombinant

Question 55

progeny that exhibit this mixing of maternal and paternal alleles on a single chromosome

Answer 55

recombinant

Question 56

Two dominant or two recessive alleles are on each chromosome

Answer 56

cis

Question 57

One dominant and one recessive allele are on each chromosome

Answer 57

trans

Question 58

correlation between crossover frequency and gene distance is used to construct ________

Answer 58

linkage maps

Question 59

distance is represented using "map units" called ______

Answer 59

centimorgans

Question 60

t/f 1 centimorgan equals 1 percent recombination

Answer 60

t

Question 61

frequency of recombination is based on the percentage of (meiotic or mitotic) divisions that break the linkage between two parental alleles

Answer 61

meiotic

Question 62

DNA sequences that serve as landmarks near genes of interest; used starting in 1980 in linkage mappings

Answer 62

genetic markers

Question 63

DNA sequences that serve as landmarks near genes of interest; used starting in 1980 in linkage mappings

Answer 63

genetic markers

Question 64

scan the genomes of thousands of individuals who have a particular phenotype for DNA sequences that they share, but are much rarer in people who do not have the trait

Answer 64

genome-wide association studies

Question 65

tightness of linkage between a marker and a gene of interest

Answer 65

logarithm of the odds

Question 66

indicates the likelihood that particular crossover frequency data indicate linkage, rather than the inheritance of 2 alleles by chance

Answer 66

LOD score

Question 67

t/f LOD scores of 3 or lesser signifies linkage

Answer 67

f

Question 68

set of DNA sequences inherited on one chromosome due to linkage disequilibrium

Answer 68

haplotype

Question 69

set of DNA sequences inherited on one chromosome due to linkage disequilibrium

Answer 69

haplotype

Question 70

t/f The farther apart two genes are on a chromosome, the more likely they are to cross over.

Answer 70

t