Final Exam Genetics Flashcards
Heritable alterations in DNA sequence
Mutations
Locations on a chromosome
Loci
An individual with two different alleles at the same locus is
Heterozygous
For complete dominance the phenotype seen in a heterozygous individual is the result of
Dominant allele
And allele who’s phenotype is not expressed in a heterozygote
Recessive allele
A cross between true breeding parents that differ at only one trait is a
Mono hybrid cross 3 to 1
Cross between parents that differ into traits 9:3:3:1
Dihybrid cross
Used to determine the genotype of one showing a dominant phenotype by mating with individual showing recessive phenotype. 1:1 or all dominant.
Also, a cross between an individual of known genotype to a homozygous recessive individual.
Test cross
Cross an F1 to an individual with an identical genotype to the parent or the actual parent
Back cross
1:2:1
Incomplete dominance. When an F1 hybrid does not resemble either true breeding parent. Intermediate phenotype where both alleles contribute to the phenotype. Pink flowers.
AaxAa
3:1
Complete dominance. AaxAa
9:3:4 AaBb x AaBb
Recessive epistasis. Case of epistasis in which the epistatic allele is recessive. labs. When the presence of two recessive alleles at one gene mask the effects of the alleles at a second Jean.
The effects of a dominant allele at one gene hide the effects of the allele at another Gene
Dominant epistasis.
9:7 AaBb x AaBb at least one dominant allele is necessary, genes working in tandem to produce a particular trait. Purple flowers in sweet peas A-B-
Complementary Gene action
Both traits show up equally in the heterozygote in the F1, in the in the F2 1:2:1. Blood group alleles (a plus B sugars) AB blood type
Codominance
Phenomenon in which a single gene determines a number of distinct and seemingly unrelated characteristics.
Plieotropy
Alternate forms of a gene are called
Alleles
Occurs in individuals who have inherited two recessive allele of the H Jean and do not produce the H carbohydrate that is precursor to A and B antigens. They may possess either or both alleles but are unable to express them. Looks type O. Recessive epistasis.
Bombay phenotype
A trait determined by more than one gene, or a gene and the environment
Multi-factorial
Phenomenon in which a single gene determines A number of distinct and seemingly unrelated characteristics. More than one effect.
Plieotropy
Indicates how many members of a population with a particular genotype show expected phenotype.
Percent penetrance
The degree or intensity with which a particular genotype is expressed
Expressivity
Process in which heterozygosity for loss of function mutant recessive allele for two different genes that affects the same pathway produces normal phenotype
Complementation
Condition in females caused by the presence of only one X chromosome
Turner syndrome
A condition caused by the presence of multiple X chromosomes in males.
Klinefelter syndrome
Tetratypes
Yeast with four different spores in an ascus
A tetrad that contains four parental class haploid cells. 2 one parent 2 the other parent
Parental ditypes
A fungal tetrad containing for recombinant spores
Non-parental ditypes
The prevention of the second crossover in a pair of homologous chromosomes
Interference
Can lead to twin spots and form a genetic mosaicism
Mitotic recombination
Sister chromatids pulled apart, centromeres split
Anaphase
Homologous chromosomes align in the middle of the meiotic spindle
Metaphase one
Chromosomes condense, mitotic spindle forms, nuclear membrane breaks down
Prophase
Chromosomes decondense, nuclear membrane forms around each identical nucleus.
Telophase
Cytoplasm divides
Cytokinesis
Chromosomes align in the middle of the mitotic spindle
Metaphase
Prophase one
Homologous chromosomes synapse, crossing over occurs
Homologous chromosomes pull apart
Anaphase one
G1 synthesis and G2
Interphase
Haploid nuclei formed
Telophase 1
The two alleles for each trait separate (segregate) during gamete formation, and then you night at random, one from each parent at fertilization.
Law of segregation
Equal. in which one allele, and only one allele, of each gene goes into each gamete
Segregation
During gamete formation, different pairs of alleles segregate independently of each other
Law of independent assortment
The kind of nuclear division followed by somatic cell division that results into daughter cells contain the same number and type of chromosomes as the original parent cell.
Mitosis
The kind of nuclear division that generates a or sperm cells containing half the number of chromosomes found in other cells within the same organism. In Germ cells, chromosomes composing each pair become segregated, so that the resulting gametes receive only one chromosome from each chromosome pair.
Meiosis
Diploid oogonia undergo mitosis to produce blank.
diploid arrested primary oocyte
Arrested primary oocyte undergoes meiosis one to produce blank polar body
First
Blank undergoes meiosis two in order to form second polar body and blank upon fertilization
Secondary oocyte, mature haploid ovum
One of three cells after miosis results in one blank
Gamete
Ooenesis begins in the blank
Fetus
Fully formed ovaries after
Six months
Blank oocytes locked in synapsis (blank) though new eggs can be reproduced in adult stem cells
Primary, prophase one
At ovulation the arrested primary oocyte completes blank and proceeds to blank of meiosis two
Meiosis one, metaphase
If oocyte is blank it completes meiosis two
Fertilized
For 30 to 45 years a woman releases one egg per month until
Menopause
Spermatogonia produce blank through mitosis
Diploid primary spermatocytes
One primary spermatocyte undergoes symmetrical meiosis one producing two blank spermatocytes
Secondary
Two secondary spermatocytes undergo symmetrical meiosis blank to yield blank spermatids
Two, four
Each primary spermatocyte yields blank haploid spermatids that mature into sperm plus X or Y
Four
Spermatogenesis begins at blank and throughout life can produce billions of sperm
Puberty
The proximity of two or more markers on chromosome. The closer together the markers are the lower the probability that they will be separated by recombination. Jeans are linked when the frequency of parental type progeny exceeds that of recombinant progeny.
Linkage
Recombinants / total # F1 = %
Recombination frequency
Total genotypes of parents / total # F1
Distance in map units
In a heterozygote, change in the base sequence of one allele to that of another allele as a result of heteroduplex formation and mismatch repair during recombination. Detected as deviation from the expected 2 to 2 segregation of parental alleles.
Gene conversion
The hydrolysis of A purine base, a or g from the deoxyribose – phosphate backbone. Unspecified base.
Depurination
The removal of an amino group -NH2 changing C to U the nitrogenous base found in RNA, transition.
DEamination
Remove damaged bases (analogues)
Bass excision repair
Corrects damage nucleotides cut backbone thymine dimers
Nucleotide excision repair
DNA polymerase inserts and incorrect nuclear tide and it’s own proofreading ability does not detect this mistake on D and methylated strand of DNA. Which method of repair?
Mismatch repair
The aims uses his minus salmonella typhiMerriam test tests for
Mutagen
Specialized sequence near the beginning of Jean, template strand
Promoter
10 base pair upstream of first transcribed nucleotide on promoter in eukaryotes. Control region helps find RNA polymerase two to recognize the promoter
Tata box
Extrinsic Terminator
Roh protein
F Met Binds to aug in prokaryotes
Shine DelGarno box
Five prime methylated guanine, three prime polly a tail, removal of Intron’s, combining of Exxons.
Modifications made to RNA in eukaryotes
Some tRNAs recognize more than one codon for the amino acid they carry, silent mutation
Wobble
Changes in one amino acid to another
Missense mutation
Alters the grouping of nucleotides into codons
Frameshift mutation
Changes code on that encodes and amino acid into a stop codon
Nonsense mutation
Complex of five small nuclear RNAs and 50 proteins organized into for nuclear ribonucleic particles eukaryotes splices RNAs
Splicosome
Catalyze a the attachment of tRNAs to corresponding amino acids
Aminoacetyl tRNA synthetases
Sites of polypeptide synthesis, amino acetyl site A peptidyl P exit site e
Ribosomes
When one mutated allele is sufficient to disrupt the entire protein function
Dominant negative
Affects gene expression or reduces Jean function
Loss of function mutation
Loss of the wild type Jean or mutation that functions less effectively
Hypomorphic
Type of mutation that results in a gene being expressed in a new place or new time
Ectopic expression
Positive regulator at a promoter. Enhances transcriptional activity
CRP camp
Relaxed usually transcriptionally active regions of the Genome
Euchromatin
condensed in all cells most of the Y
constitutive Heterochromatin
Condensed only in some cells
Facultative heterochromatin
Variable expression of a gene in a population of cells caused by the jeans location near highly compacted heterochromatin
Position effect variegation
Enzymes that ad acetyl groups to lysine residues in histone tails in order to open up chromatin and allow transcription
Histone acetyltransferases hats
Close chromatin and repress transcription remove acetyl groups
Histone deacetylase
Enzymes that methylate histone tails
Histone methyltransferases (HMTS)
Group of proteins responsible for holding sister chromatids together until their separation in anaphase or anaphase 2
Cohesins
Ribosomal RNA is transcribed by…
RNA polymerase one
Messenger RNA and MiRNA are transcribed by…
RNA polymerase Two
TRNA is transcribed by…
RNA polymerase III
Tata binding protein is a…
Basal transcription factor
Eukaryotic transcription factors that bind specific DNA sites near a gene and prevent the initiation of transcription of the gene by recruiting call repressor proteins that either prevent the RNA polymerase II complex from finding the promoter or modify histones to close chromatin structure
Repressors
Eukaryotic transcription factors that bind specific DNA sites near a gene and prevent the initiation of transcription of the gene by recruiting call repressor proteins that either prevent the RNA polymerase II complex from finding the promoter or modify histones to close chromatin structure
Insulator
Competition due to overlaping binding sites, quenching, (repressor blocks activation domain) cytoplasmic sequestration, heterodimerization
Ways a repressor can decrease the level of transcription of a specific gene
Methylation CPG islands is associated with…
Silencing
A maternally imprinted Jean is…
Silent
A paternally imprinted Jean is…
Silent
Geneticist use DSRNAs and SIRNA is to decrease blank expression and help determine the function of a blank product.
Gene
Molecular signals that influence cell growth and division
Growth factor
Growth factors that stimulate cell proliferation
Mytogens
Proteins who’s levels fluctuate during the cell cycle. They specify which set of proteins are phosphorylated..
Cyclins
Proteins that can phosphorylate other proteins when bound to molecules who’s levels rise and fall during the cell cycle
Cyclin dependent kinases
To hit hypothesis. Both copies of jeans and coding P 53 or RB need to be mutated because they function as…
Tumor suppressor genes
Proteins with signal binding site outside the cell, transmembrane segment, and and intracellular domain
Growth factor receptors
When mutated, jeans and coding receptors and signal transducers like Ras can become…
Oncogenes
Translocation between chromosomes 9 and 22 that is associated with chronic myelogenous leukemia is called…
Philadelphia chromosome
Proteins with signal binding site outside the cell, transmembrane segment, and and intracellular domain
Growth factor receptor
Also called microsatellites, 1 to 10 bases repeated in tandem 10 to 100 times occur once in every 30 kilobases have no effect except in trinucleotide repeats within jeans. Highly polymorphic.
Simple sequence repeats
Short insertions or deletions of a single base pair or a few base pairs, occur once about every 10 kilobases
Deletion - insertion polymorphisms
Large blocks of duplications or deletions from 100 BP to 10 mb. Most are inherited. Highly polymorphic because of their potential for unequal crossing over.
Copy number variants
Codis uses, Huntington’s disease
Simple sequence repeat SSRS
A technique that uses A restriction enzyme that will cut one SnP but not another
Restriction fragment length polymorphisms RFLP
It is more likely that a disease Jean and DNA marker are linked
Lod score of 3
Cystic fibrosis has a number of mutations occurring in the same gene.
Allelic heterogeneity
The alleles carried by all members of a population
Gene pool
Allows geneticists to model allele frequency changes over many generations in a set number of individuals of each genotype
Monty Carlo simulation
A situation which leads to balancing selection
Heterozygote advantage
When W equals zero
No individuals of that genotype survive to reproduce
When Carl Coren’s used pollen from a verigated 4 o’clock plant to fertilize eggs from Green 4 o’clock plant the F1 offspring were always blank like the blank parent
Green, maternal.
Cells that contain mitochondria that are genetically different are
Heteroplasmic plasmic
Which tissue would be affected with the lowest percentage of mutant mitochondria?
Nervous tissue
The evolution of Homo sapiens is best explained by the
Out of Africa hypothesis
Helix loop helix, zinc finger, helix turn helix
Examples of DNA binding
Example of dimerization
Leucine zipper
Uses DDNtps to determine order of nucleotides
DNA sequencing
Imprinting. Post transcriptional modifications (splicing, stability, tissue specific expression). Protein (stability location, modification). DNA methylation.
Mechanisms of gene expression
Growth advantage. Not being subject to cell cycle. Mutation in DNA repair mechanisms. Contact inhibition. Immune surveillance. Autocrine stimulation. Angiogenesis. Express telomerase. breakthrough Basal membranes. Metastasize.
How a cancer cell differs from a normal cell
FSH, harvests eggs, fertilization in Vitro, incubate eggs, 6 to 10 cell stage, micropipette, genotype embryo, PCR, gel electrophoresis, parents can make an informed decision, selection for implantation in the woman’s uterus.
The steps required for pre-implantation embryo diagnosis
One. The population has an infinite number of individuals. Two. Individuals mate at random. Three. No new mutations appear. Four. No migration into or out of the population. Five. Genotypes have no affect on ability to survive and transmit alleles to the next generation.
Hardy Weinberg assumptions
- Lynn Margulis. 2. Mitochondria and chloroplasts have their own DNA which replicates independently of the cell cycle. 3. DNA is not organized into nucleosomes. 4. N-formyl methionine & tRNAfmet are used in translation. 5. Inhibitors of bacterial translation block mitochondria and chloroplasts translation. 6.Comparisons of ribosomal are any gene sequences suggest mitochondrial genomes derived from gram-negativeNonsulfur purple bacteria while chloroplasts come from cyanobacteria.
Endosymbiotic theory
{A}a
Imprinting disease, disease expressed
A{a}
Imprinting, not expressing the disease, carrier
Prader Willi
Maternally imprinted, Gene is passed from father
Angelman syndrome
Paternally imprinted, Gene passed down from mother
p2 + 2pq + p2 = 1
Hardy Weinberg equilibrium
p+ q = 1
Sum of allele frequencies
q = square root of q2
Definition of q
2pq
Carrier frequency
Prader Willi
Maternally imprinted, Gene is passed from father
Angelman syndrome
Paternally imprinted, Gene passed down from mother
p2 + 2pq + p2 = 1
Hardy Weinberg equilibrium
p+ q = 1
Sum of allele frequencies
q = square root of q2
Definition of q
2pq
Carrier frequency
Love-faumeni syndrome
P 53- tumor suppressor gene
Mitochondrial. maternally inherited
Heteroplasmic inheritance
Caused by loss of function mutations in mitochondrial transfer RNA jeans. Affects the translation of all mitochondrial messenger RNA’s. Homoplasmic cells could not survive so all affected individuals are heteroplasmic. Severity of the phenotype depends on percentage of mutant mitochondrial DNA. Maternal inheritance. Not all children are affected. Affected to different degrees. Hi energy requirement tissues are less tolerant of the mutation.
Myoclonic epilepsy and ragged red fiber (merrf) disease
