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Flashcards in Exam 1 Deck (75)
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1
Q

What causes early death and thus does not appear among the progeny?

A

Lethal allele

2
Q

The translocation of chromosome 21 onto another chromosome results in?

A

Familial Down Syndrome

3
Q

What is an example of multiple alleles?

A

ABO blood group

4
Q

What is a complete set of genetic instructions for any organism?

A

Genome

5
Q

What condition arises when cells within the same person have a different genetic makeup?

A

Mosaicism

6
Q

What it the degree to which a character is expressed?

A

Expressivity

7
Q

What is a trait that is shared by both members of a twin pair?

A

Concordant trait

8
Q

What is the term for an improvement of function of any biological quality in a hybrid offspring of two pure bred strains?

A

Hybrid vigor

9
Q

What reasons are there against gene editing?

A

Technical issues still need to be worked out, ethical concerns need to be worked out, or could lead to eugenic

10
Q

What protein complex holds chromatids together?

A

Cohesin

11
Q

What occurs when crossing over is unequal?

A

Deleted or duplicated regions

12
Q

What relationship do the alleles of a patient who is heterozygous for cystic fibrosis show at the chloride transport level?

A

Incomplete dominance

13
Q

What are some disadvantages of fluorescent in situ hybridization?

A

Requires physician to suspect diagnosis, expensive, and epigenetic changes are not detected

14
Q

Why are chromosomes painted with fluorescent-tagged chromosome specific DNA sequences?

A

Allows for visualization of specific chromosomes or chromosome segments

15
Q

What probability rule is used to determine the occurance of mutually exclusive events?

A

Addition rule

16
Q

What is a set of DNA variations, or polymorphisms, that tend to be inherited together?

A

Haplotype

17
Q

What are some of the assumptions of a Chi Square Goodness of Fit test?

A

Samle data is random, samle size if large enough, and observations are independent of each other

18
Q

What theory states that cells in the reproductive organs carry a complete set of genetic informaiton that is passed to the egg and the sperm?

A

Germ-plasm theory

19
Q

What is it called when a genetic trait becomes more strongly expressed or is expressed at an earlier stage as it is passed down generation to generation?

A

Anticipation

20
Q

What checkpoint is only passed if DNA is completely replicated and undamaged?

A

G2/M

21
Q

True/False: G banding strains heterochromatin more intensely because it is GC-rich

A

False: AT-rich

22
Q

How does sickle cell disease demnstrate pleiotropy?

A

Only one gene is mutated but leads to many effects such as blindness, liver fialurem and heart attack.

23
Q

What states that when two different alleles are present in a genotype only one of those alleles will be observed in the phenotype?

A

The concept of dominance

24
Q

What is affected by lethal alleles?

A

Mendelian genotypic and phenotypic ratios

25
Q

What are common complications of defect checkpoints?

A

Cancers

26
Q

What type of trait is inherited from changes in a chromosome without alterations in the DNA sequence?

A

Epigenetic trait

27
Q

What is the tendency of alleles that are located close together to be inherited together called?

A

Genetic linkage

28
Q

What checkpoint of interphase serves as the regulated decision point?

A

G1/S

29
Q

What occurs when one gene influences two or more seemingly unrelated phenotypes?

A

Pleiotropy

30
Q

What is it called when an inversion during mieosis results in one of the four chromatids having two centromeres?

A

Dicentric

31
Q

What is the exchange of genetic material between homologous chromosomes? (Results in shuffling of genes along the chromosome)

A

Crossing over

32
Q

What is the general method of G staining?

A

Heterochromatin is stained intensely, bands can be seen in metaphase chromosomes

33
Q

What type of mapping is determined by recombinant frequency?

A

Genetic mapping

34
Q

What are some disadvanteges of G banding?

A

Requires lots of training, cannot detect epigenetic changes, cannot determine presence of cancer

35
Q

Aneuploidy of the sex chromosomes when a male has an extra X chromosome.

A

Klinefelters

36
Q

What type of chromosomal abnormality occurs before a fetus is born?

A

Constitutional

37
Q

What is the term for a cell or organism containing more than two complete sets of chromosomes?

A

Polyploidy

38
Q

What does it mean when a given locus has more than two allels present within a group of individuals?

A

Multiple alleles

39
Q

What reasons are there for gene editing?

A

Can terminate genetic disease, if it is safe and will make a big difference, or if there is no other option

40
Q

What is the term for the presence of the same trait in both members of a pair of twins?

A

Concordance

41
Q

What is the attachment point for spindle microtubules?

A

Centromeres

42
Q

What is the typical cause of trisomy 21?

A

Random nondisjunction formation in egg formation

43
Q

What is mandated by the Genetic Information Nondiscrimination Act?

A

It is illegal to discriminate against employees or applicants because of genetic information

44
Q

How does the IGF2 gene demonstrate the concept of imprinted genes?

A

The maternal gene is modified via methylation during gametogenesis thus preventing transcription in offspring. Therefore the paternal alleleis exclusively expressed in the offspring.

45
Q

What are the tips of linear chromosomes?

A

Telomeres

46
Q

What is significant about cytoplasmic inheritance?

A

Cytoplasm is usually inherited from one parent

47
Q

What does it mean when one gene masks or influences that effect of another gene?

A

Epistasis

48
Q

Huntington’s disease and Fragile X syndrome demonstrate anticipation. What is the commonality between these two diseases that results in anticipation?

A

Mutation of expanding nucleotide repeats. The more these repeats mutate and are expressed the more severly the disease is expressed.

49
Q

What is the passing on of physical or mental characteristics genetically from one generation to another?

A

Heredity

50
Q

What type of mapping is determined by nucleotide position?

A

Physical mapping

51
Q

BRCA genes are inherited in a dominant fashion. However sex and the parent contributing the gene affect the likelihood their offspring will express the phenotype. What concept does this demonstrate?

A

Penetrance

52
Q

What was the goal of the Human Genome Project?

A

Complete mapping and understanding of all genes of human beings

53
Q

What is the control of genes present on autosomes by the individuals sex?

A

Sex influenced traits

54
Q

Acquired chromosomal abnormalities are involved in only one organ. What is usually the complication of this abnormality?

A

Cancer

55
Q

What type of mutation results from the loss or gain of chromosomes?

A

Aneuploidy

56
Q

A dihybrid cross between two heterozygous individuals will result in what ratio?

A

9:3:3:1

57
Q

What is the percentage of individuals having a particular genotype that express the expected phenotype?

A

Penetrance

58
Q

What is the proportion of total variation between individuals in a given population that is due to genetic variation?

A

Heritability

59
Q

What are sites on chromosomes prone to break under certain conditions termed?

A

Fragile sites

60
Q

Which genes are tumor suppressors that are important in DNA repiar?

A

BRCA

61
Q

Aneuploidy of the sex chromosomes when a female have one X chromosome.

A

Turner syndrome

62
Q

What probability rule is used to determine independent events happing sinultaneously?

A

Multiplicaiton rule

63
Q

What is the process of inactivation of 1 X chromosome to compensate for different X dosage between the sexes?

A

Dosage compensation

64
Q

What is the inheritance of characteristics encoded by genes located in the cytoplasm?

A

Cytoplasmic inheritance

65
Q

What are some sources of aneuploidy?

A

Deletion of centromere during mitosis and meiosis, Robertsonian translocation, and nondisjunction during meiosis and mitosis

66
Q

What type of mutation results in a segment of chromosome being moved to a nonhomologous chromosome or to another place on the same chromosome?

A

Translocation

67
Q

What is the non-random association of alleles at different loci?

A

Linkage disequilibrium

68
Q

What are some advantages of G banding?

A

Rapid and robust, can detect numerical abnormalities/structural rearragnements/large deletions or duplications

69
Q

What is the purpose of using a Chi-Square Goodness of Fit test?

A

Determines the probability that the difference between the observed and expected values are due to chance

70
Q

What relationship do the alleles of a patient who is heterozygous forcystic fibrosis show at the channel localization level?

A

Co-dominant

71
Q

How might a female carrier for Hemophilia have complications?

A

Inactivation of the “wrong” X chromosome could lead to mosaicism causing hemophilia-like complicaitons

72
Q

Why have states began to mandate certain postnatal genetic screenings?

A

If disease is detected early it can be cured and screenings have begun to be more cheaper

73
Q

What are some advantages of fluorescent in situ hybridization?

A

Does not require dividing cells, quick screening of a large number of cells, quick results, confirmation test for G banding, can detect tissue specific mosaicism

74
Q

What states that alleles segregate independently when gametes are formed?

A

Independent assortment

75
Q

What states that each individual diploid organism posseses two alleles for any particular characteristic an only one passes on to its offspring?

A

Principle of segregation