Exam 1 Flashcards
What causes early death and thus does not appear among the progeny?
Lethal allele
The translocation of chromosome 21 onto another chromosome results in?
Familial Down Syndrome
What is an example of multiple alleles?
ABO blood group
What is a complete set of genetic instructions for any organism?
Genome
What condition arises when cells within the same person have a different genetic makeup?
Mosaicism
What it the degree to which a character is expressed?
Expressivity
What is a trait that is shared by both members of a twin pair?
Concordant trait
What is the term for an improvement of function of any biological quality in a hybrid offspring of two pure bred strains?
Hybrid vigor
What reasons are there against gene editing?
Technical issues still need to be worked out, ethical concerns need to be worked out, or could lead to eugenic
What protein complex holds chromatids together?
Cohesin
What occurs when crossing over is unequal?
Deleted or duplicated regions
What relationship do the alleles of a patient who is heterozygous for cystic fibrosis show at the chloride transport level?
Incomplete dominance
What are some disadvantages of fluorescent in situ hybridization?
Requires physician to suspect diagnosis, expensive, and epigenetic changes are not detected
Why are chromosomes painted with fluorescent-tagged chromosome specific DNA sequences?
Allows for visualization of specific chromosomes or chromosome segments
What probability rule is used to determine the occurance of mutually exclusive events?
Addition rule
What is a set of DNA variations, or polymorphisms, that tend to be inherited together?
Haplotype
What are some of the assumptions of a Chi Square Goodness of Fit test?
Samle data is random, samle size if large enough, and observations are independent of each other
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?
Germ-plasm theory
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?
Anticipation
What checkpoint is only passed if DNA is completely replicated and undamaged?
G2/M
True/False: G banding strains heterochromatin more intensely because it is GC-rich
False: AT-rich
How does sickle cell disease demnstrate pleiotropy?
Only one gene is mutated but leads to many effects such as blindness, liver fialurem and heart attack.
What states that when two different alleles are present in a genotype only one of those alleles will be observed in the phenotype?
The concept of dominance
What is affected by lethal alleles?
Mendelian genotypic and phenotypic ratios
What are common complications of defect checkpoints?
Cancers
What type of trait is inherited from changes in a chromosome without alterations in the DNA sequence?
Epigenetic trait
What is the tendency of alleles that are located close together to be inherited together called?
Genetic linkage
What checkpoint of interphase serves as the regulated decision point?
G1/S
What occurs when one gene influences two or more seemingly unrelated phenotypes?
Pleiotropy
What is it called when an inversion during mieosis results in one of the four chromatids having two centromeres?
Dicentric
What is the exchange of genetic material between homologous chromosomes? (Results in shuffling of genes along the chromosome)
Crossing over
What is the general method of G staining?
Heterochromatin is stained intensely, bands can be seen in metaphase chromosomes
What type of mapping is determined by recombinant frequency?
Genetic mapping
What are some disadvanteges of G banding?
Requires lots of training, cannot detect epigenetic changes, cannot determine presence of cancer
Aneuploidy of the sex chromosomes when a male has an extra X chromosome.
Klinefelters
What type of chromosomal abnormality occurs before a fetus is born?
Constitutional
What is the term for a cell or organism containing more than two complete sets of chromosomes?
Polyploidy
What does it mean when a given locus has more than two allels present within a group of individuals?
Multiple alleles
What reasons are there for gene editing?
Can terminate genetic disease, if it is safe and will make a big difference, or if there is no other option
What is the term for the presence of the same trait in both members of a pair of twins?
Concordance
What is the attachment point for spindle microtubules?
Centromeres
What is the typical cause of trisomy 21?
Random nondisjunction formation in egg formation
What is mandated by the Genetic Information Nondiscrimination Act?
It is illegal to discriminate against employees or applicants because of genetic information
How does the IGF2 gene demonstrate the concept of imprinted genes?
The maternal gene is modified via methylation during gametogenesis thus preventing transcription in offspring. Therefore the paternal alleleis exclusively expressed in the offspring.
What are the tips of linear chromosomes?
Telomeres
What is significant about cytoplasmic inheritance?
Cytoplasm is usually inherited from one parent
What does it mean when one gene masks or influences that effect of another gene?
Epistasis
Huntington’s disease and Fragile X syndrome demonstrate anticipation. What is the commonality between these two diseases that results in anticipation?
Mutation of expanding nucleotide repeats. The more these repeats mutate and are expressed the more severly the disease is expressed.
What is the passing on of physical or mental characteristics genetically from one generation to another?
Heredity
What type of mapping is determined by nucleotide position?
Physical mapping
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?
Penetrance
What was the goal of the Human Genome Project?
Complete mapping and understanding of all genes of human beings
What is the control of genes present on autosomes by the individuals sex?
Sex influenced traits
Acquired chromosomal abnormalities are involved in only one organ. What is usually the complication of this abnormality?
Cancer
What type of mutation results from the loss or gain of chromosomes?
Aneuploidy
A dihybrid cross between two heterozygous individuals will result in what ratio?
9:3:3:1
What is the percentage of individuals having a particular genotype that express the expected phenotype?
Penetrance
What is the proportion of total variation between individuals in a given population that is due to genetic variation?
Heritability
What are sites on chromosomes prone to break under certain conditions termed?
Fragile sites
Which genes are tumor suppressors that are important in DNA repiar?
BRCA
Aneuploidy of the sex chromosomes when a female have one X chromosome.
Turner syndrome
What probability rule is used to determine independent events happing sinultaneously?
Multiplicaiton rule
What is the process of inactivation of 1 X chromosome to compensate for different X dosage between the sexes?
Dosage compensation
What is the inheritance of characteristics encoded by genes located in the cytoplasm?
Cytoplasmic inheritance
What are some sources of aneuploidy?
Deletion of centromere during mitosis and meiosis, Robertsonian translocation, and nondisjunction during meiosis and mitosis
What type of mutation results in a segment of chromosome being moved to a nonhomologous chromosome or to another place on the same chromosome?
Translocation
What is the non-random association of alleles at different loci?
Linkage disequilibrium
What are some advantages of G banding?
Rapid and robust, can detect numerical abnormalities/structural rearragnements/large deletions or duplications
What is the purpose of using a Chi-Square Goodness of Fit test?
Determines the probability that the difference between the observed and expected values are due to chance
What relationship do the alleles of a patient who is heterozygous forcystic fibrosis show at the channel localization level?
Co-dominant
How might a female carrier for Hemophilia have complications?
Inactivation of the “wrong” X chromosome could lead to mosaicism causing hemophilia-like complicaitons
Why have states began to mandate certain postnatal genetic screenings?
If disease is detected early it can be cured and screenings have begun to be more cheaper
What are some advantages of fluorescent in situ hybridization?
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
What states that alleles segregate independently when gametes are formed?
Independent assortment
What states that each individual diploid organism posseses two alleles for any particular characteristic an only one passes on to its offspring?
Principle of segregation
