Unit 2 Part 2: Non-Mendelian Genetics

Question 1

Responsible for the traits that Mendel studied in pea plants were on different chromosomes.

Answer 1

Genes

Question 2

T/F: When genes are close to each other on the same chromosome, they usually segregate at random during meiosis and therefore their expression does not support Mendel’s predictions.

Answer 2

F; do not segregate

Question 3

Genes close on a chromosome are packaged into the same gametes and are said to be ______

Answer 3

linked

Question 4

Refers to the transmission of genes on the same chromosome

Answer 4

Linkage

Question 5

Who identified more than 50 genes on Drosophila’s 4 pairs of chromosomes?

Answer 5

Thomas Morgan

Question 6

Do not assort independently and do not produce Mendelian ratios for crosses tracking two or more genes

Answer 6

Linked Genes

Question 7

He discovered that many seemed to be linked together. They are almost always inherited together & only rarely become separated.

Answer 7

Thomas Morgan

Question 8

Grouped genes into 4 linkage groups

Answer 8

Thomas Morgan

Question 9

Linkage maps were first developed by?

Answer 9

Alfred Sturtevant

Question 10

A map based on the frequencies of combination between markers during crossover of homologous chromosome

Answer 10

Linkage Map

Question 11

A map of the genes on chromosome based on linkage analysis

Answer 11

Linkage Mapping

Question 12

T/F: A linkage map does not show the physical distances between genes but rather their relative position, as determined by how Gene loci are inherited together.

Answer 12

T

Question 13

Some DNA sequences are nearly always inherited together, like two inseparable friends. This nonrandom association between DNA sequences is called

Answer 13

Linkage Disequilibrium (LD)

Question 14

The human genome consists of many LD blocks, where stretches of alleles stick together, interspersed with areas where crossing over is prevalent. LD blocks, called __________, could be used to track genes in populations.

Answer 14

haplotypes

Question 15

Is a combination of alleles at multiple linked loci that are transmitted together

Answer 15

Haplotype

Question 16

May refer to as few as 2 loci or to an entire chromosome depending on the number of recombination events that occurred between a given set of loci

Answer 16

Haplotype

Question 17

The term haplotype is a portmantaeu of ________

Answer 17

Haploid Genotype

Question 18

Is a set of single nucleotide polymorphisms (SNPs) on a single chromatid that are statistically associated

Answer 18

Haplotype

Question 19

T/F: Sex is determined by genetic information in human

Answer 19

T

Question 20

It extensively controls physical, psychological, and behavioral traits which are also influenced by genetic information

Answer 20

Sex-Linked Traits

Question 21

may be categorized by how sex affects phenotypic traits, including sex itself as a trait (i.e., sex determination), sex-linked trait, sex-limited trait, and sex- influenced trait

Answer 21

Sex-related genetics

Question 22

Genes on the Y chromosome

Answer 22

Y-linked

Question 23

Genes on the X chromosome

Answer 23

X-linked

Question 24

T/F: Y-linked traits are rare because the chromosome has few genes, and many of its genes have counterparts on the X chromosome.

Answer 24

T

Question 25

T/F: X-linked traits are passed from male to male, because a female does not have a X chromosome.

Answer 25

F; Y-linked traits are passed from male to male, because a female does not have a Y chromosome.

Question 26

T/F: No other Y-linked traits besides infertility (which obviously can’t be passed on) are yet clearly defined.

Answer 26

T

Question 27

T/F: Some traits at first attributed to the Y chromosome are actually due to genes that have been inserted into that chromosome from other chromosomes, such as a deafness gene.

Answer 27

T

Question 28

Part of Chromosome Mutation = Infertility

Answer 28

SRY

Question 29

Part of Chromosome Controlled by multiple genes

Answer 29

Tooth Enamel Formation

Question 30

Part of Chromosome Mutation = Male can produce necessary fluids but no sperm; angospermia

Answer 30

AZF / Azoospermia Factor

Question 31

Part of Chromosome Pseudoautosomal regions - create homology between X & Y chromosomes

Answer 31

PAR2

Question 32

T/F: A disproportionate number of X-linked genes cause illness when mutant. The chromosome includes 4 percent of all the genes in the human genome, but **accounts for about 10 percent of Mendelian** (single-gene) diseases.

Answer 32

T

Question 33

T/F: X-linked diseases are more common in males

Answer 33

T

Question 34

T/F: In males, X-linked traits are passed just like autosomal traits—that is, two copies are required for expression of a recessive allele and one copy for a dominant allele.

Answer 34

F; females

Question 35

T/F: In males, however, a single copy of an X-linked allele causes expression of the trait or illness because there is no copy of the gene on a second X chromosome to mask the effect. A man inherits an X-linked trait only from his mother.

Answer 35

T

Question 36

The human male is considered __________ for X-linked traits, because he has only one set of X- linked genes.

Answer 36

hemizygous

Question 37

X-Linked Recessive or X-Linked Dominant Always expressed in the male

Answer 37

X-Linked Recessive

Question 38

X-Linked Recessive or X-Linked Dominant Affected male inherits trait from heterozygote or homozygote

Answer 38

X-Linked Recessive

Question 39

X-Linked Recessive or X-Linked Dominant Affected female inherits trait from the affected father and affected or heterozygote mother

Answer 39

X-Linked Recessive

Question 40

X-Linked Recessive or X-Linked Dominant Expressed in a female homozygote and very rarely in a female heterozygote

Answer 40

X-Linked Recessive

Question 41

X-Linked Recessive or X-Linked Dominant Expressed in females in one copy

Answer 41

X-Linked Dominant

Question 42

X-Linked Recessive or X-Linked Dominant Much more severe effects in males

Answer 42

X-Linked Dominant

Question 43

X-Linked Recessive or X-Linked Dominant High rates of miscarriage due to early lethality in males

Answer 43

X-Linked Dominant

Question 44

X-Linked Recessive or X-Linked Dominant Passed from male to all daughters but to no sons

Answer 44

X-Linked Dominant

Question 45

The X-linked recessive trait, the blood- clotting disease hemophilia B is also known as

Answer 45

Christmas disease and factor IX (“FIX”) deficiency

Question 46

A rare neurodevelopmental disorder. Less lethal than HD

Answer 46

Rett Syndrome

Question 46

T/F: In X-linked dominant inheritance, if male is affected, daughter will always affected

Answer 46

T

Question 47

A ________ affects a structure or function of the body that is present in only males or only females. The gene for such a trait may be ________.

Answer 47

Sex-limited trait , autosomal

Question 48

Typical child with this syndrome cannot speak, use her hands, walk, eat or breathe easily

Answer 48

Rett Syndrome

Question 48

Are due to genes on autosomes, and the expression of these traits are limited so that normally only one sex is affected.

Answer 48

Sex-limited traits

Question 49

Although an inherited disease that causes symptoms associated with pregnancy is obviously sex-limited, the male genome may play a role by contributing to the development of supportive structures, such as the ________

Answer 49

Placenta

Question 50

A sudden rise in blood pressure late in pregnancy

Answer 50

Preeclampsia

Question 51

T/F: If a man’s first wife had preeclampsia, his second wife had double the risk of developing it

Answer 51

T

Question 51

are autosomal traits that are influenced by sex. If a male has one recessive allele, he will show that trait, but it will take two recessive for the female to show that same trait. One such gene is baldness.

Answer 51

Sex-influenced traits

Question 52

Traits that may be expressed in both sexes but occurs more frequently in one sex

Answer 52

Sex-influenced traits

Question 53

T/F: Single genes seldom completely control a phenotype in the way that Mendel’s experiments with peas suggested.

Answer 53

T

Question 54

A genotype (allele combination) that causes death

Answer 54

Lethal Allele Combinations

Question 55

Tay-Sachs disease is lethal by age of

Answer 55

3 or 4

Question 56

Causes death before the individual can reproduce, which prevents passage of mutations to the next generation.

Answer 56

Lethal Genotype

Question 57

T/F: Achondroplastic Dwarfism is an autosomal dominant trait, but is most often the result of a spontaneous (new) mutation.

Answer 57

T

Question 58

A lethal genotype in humans is _______________, which has the distinct phenotype of a long trunk, short limbs, and a large head bearing a flat face.

Answer 58

Achondroplastic Dwarfism

Question 59

Type of relationship between alleles, with a heterozygote phenotype intermediate between the two homozygote phenotypes

Answer 59

Incomplete Dominance

Question 60

When F1 generation (all pink flowers) is self pollinated, the F2 generation is 1:2:1 red, pink, white

Answer 60

Incomplete Dominance

Question 61

T/F: Enzyme deficiencies in which a threshold level is necessary for health illustrate incomplete dominance only.

Answer 61

F; both complete and incomplete dominance

Question 62

Is an example of incomplete dominance that can be observed in carriers on both the molecular and whole-body levels

Answer 62

Familial hypercholesterolemia (FH)

Question 63

Different alleles that are both expressed in a heterozygote are codominant.

Answer 63

Co-dominance

Question 64

The ABO blood group system is based on the expression of __________ ______.

Answer 64

Codominant Alleles

Question 65

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

Answer 65

Pleiotropy

Question 65

Both alleles are simultaneously expressed in the heterozygote

Answer 65

Codominant Traits

Question 65

It refers to interaction between different genes, not between the alleles of the same gene

Answer 65

Epistasis

Question 66

A gene that affects expression of another

Answer 66

Modifier Gene

Question 67

A familiar epistatic interaction is ________, in which one gene blocks the action of genes that confer color.

Answer 67

albinism

Question 68

Bombay Phenotype

Answer 68

Epistasis

Question 69

It results from an interaction between a gene called H and the I gene that confers ABO blood type. The H gene controls the placement of a molecule to which antigens A and B attach on red blood cell surfaces.

Answer 69

Bombay Phenotype

Question 70

Bombay was named by

Answer 70

Dr. Bhande

Question 70

T/F: Individual with Bombay phenotype can receive blood only from Bombay blood group people

Answer 70

T

Question 71

The most common form of this autosomal dominant condition is a defect in an elastic connective tissue protein called fibrillin. The protein is abundant in the lens of the eye, in the aorta (the largest artery in the body, leading from the heart), and in bones of the limbs, fingers, and ribs.

Answer 71

Marfan syndrome (Pleiotropy)

Question 72

It can occur when genes encode enzymes or other proteins that are part of the same biochemical pathway, or when proteins affect the same body part

Answer 72

Genetic Heterogeneity

Question 73

osteogenesis imperfecta

Answer 73

Genetic Heterogeneity

Question 73

An environmentally caused trait that appears to be inherited

Answer 73

Phenocopy

Question 74

Such a trait can either produce symptoms that resemble those of a known single-gene disease or mimic inheritance patterns by affecting certain relatives.

Answer 74

Phenocopy

Question 75

The limb birth defect caused by the drug ________ is a phenocopy of the rare inherited illness phocomelia.

Answer 75

thalidomide

Question 76

A birth defect caused by exposure to a widely used teratogen was more likely than a sudden increase in incidence of a rare inherited disease.

Answer 76

Phocomelia (Phenocopy)

Question 77

Regulate organ development

Answer 77

Homeotic genes

Question 78

Code for transcription factors

Answer 78

Homeobox genes

Question 79

Determine the identities of each body segment

Answer 79

Hox genes

Question 80

Refers to the percentage of individuals who have a particular genotype who have the associated phenotype

Answer 80

Penetrance

Question 80

Refers to variability in severity of a phenotype, or the extent to which the gene is expressed

Answer 80

Expressivity

Question 81

T/F: Complete penetrance is rare.

Answer 81

T

Question 82

Refers to the inheritance of a trait governed by more than one genes. Generally, three or more genes govern the inheritance of polygenic traits. Multiple independent genes have an additive or similar effect on a single quantitative trait.

Answer 82

Polygenic Traits

Question 83

Type 2 diabetes mellitus

Answer 83

Polygenic Disorder

Question 84

A polygenic disorder with multiple genes located on different chromosomes contributing to its susceptibility.

Answer 84

Type 2 diabetes mellitus