Term
| Recombination repair of thymine dimers in DNA after exposure to UV light does wat ? |
|
Definition
1. Moves two adenines from the original DNA strand to the newly-replicated DNA strand
2. may not be able to cope with accumulation of DNA damage caused by frequent exposure to UV light. |
|
|
Term
ATTG ----> AGTG
the change in the DNA sequence given above is... |
|
Definition
1. point mutation
2. transverstion
3. base substitution |
|
|
Term
| tautomeric shifts in nitrogenous bases in DNA |
|
Definition
1. occur when a proton (H+) changes position within the molecule
2. change thymine so it pairs with guanine
3. change cytosine so it pairs with adenine.
4. can be induced by incorporating 5-brouracil into DNA |
|
|
Term
| The hormone-responsive element (HRE) estrogen: |
|
Definition
1. is an inverted repeat
2. is the binding site for the receptor protein / hormone complex
3. is located in the 5' upstream region of genes that are up-regulated by estrogen |
|
|
Term
|
Definition
Can be either upstream or downstream of gene
Accelerate the rate of transcription of the gene |
|
|
Term
|
Definition
places a methyl lgroup on cytosine bases that are immediately upstream of guanine
Inactivates on X chromosome at random in every female cell in mammals
Creates Barr bodies |
|
|
Term
|
Definition
| Increases the number of homozygotes in the population |
|
|
Term
| humans can live to become adults with which of the following abnormal chromosome conditions? |
|
Definition
|
|
Term
| if you genetically engineer the imported carp to make them sterile you would make them... |
|
Definition
|
|
Term
| The acridine dye proflavin |
|
Definition
intercalates between bases in the DNA molecule
Causes frameshift mutation |
|
|
Term
| Triple-repeat (trinucleotide) mutations in humans are known to cause: |
|
Definition
huntington's disease
fragile X syndrome |
|
|
Term
| Which of the following statements apply to transformed cells |
|
Definition
they maintain telomerase production and can divide indefinitely
They often develop genetic abnormalities such as aneuploidy |
|
|
Term
|
Definition
have accumulated mutations in several key genes
often have an inactivated p53 gene
Often have demethylated DNA |
|
|
Term
| a human individual with the sex chromosome constitution XO would be classified as havin which ONE of the following |
|
Definition
|
|
Term
| Turner's syndrome is most likely caused by .... |
|
Definition
| NON- DISJUNCTION AT meiosis |
|
|
Term
| alternate mRNA splicing in mouse salivary glands and liver cells results in |
|
Definition
| faster translation in the salivary gland than in the liver |
|
|
Term
| despite being deleterious, the sickle cell mutant allele A2 in human populations has an unusually high frequency in human populations in regions where malaria occurs because... |
|
Definition
heterozygous (A1A2) individuals exposed to malaria have a higher relative fitness than A1A1 and A2A2 individuals
heterozygote superiority keeps both A1 and A2 alleles in the gene pool |
|
|
Term
| Duchenne muscular dystrophy, a disease that causes progressive muscle loss and paralysis, is caused by an x-linked recessive mutation. If 60 males in Fort collins (population 120,000) suffer from DMD how many female carriers of the mutation would you expect in the town? |
|
Definition
| 120 (doubles because they have a twice the chance of being a carrier / having it.) |
|
|
Term
| in a population of cockroaches exposed to an insecticide 80% die before reproducing. the initial frequency of the resistance allele R is .05 what is the selection coefficient of the susceptible (rr) gene |
|
Definition
| 80% die to it is selected for 20% of the time. |
|
|
Term
| in addition to genetic drift which of the following would be of concern to a conservation biologist working to achieve long term viability of the desert bighorn herd |
|
Definition
lack of migration and gene flow with other herds
interbreeding
limited genetic diversity |
|
|
Term
| which of the following will reduce the effective population size (Ne) ? |
|
Definition
some individuals in a population are infertile or too old to breed
One successful male mates with a number of females
population crashes and is bottlenecked for two generations before recovering |
|
|
Term
|
Definition
| one ciston for each enzyme |
|
|
Term
| auto regulation (feedback) |
|
Definition
| if protein sits on a promoter it will block transcription |
|
|
Term
|
Definition
| inhibitor on promoter blocks transcription but an inducer can bind to it and allow transcription |
|
|
Term
|
Definition
| if an effector is absent no transcription but if it binds to the promoter it will allow it |
|
|
Term
|
Definition
| promoter /operator complec only controls genes downstream of them |
|
|
Term
|
Definition
- methyl group added to cytosine in dinucleotides
-heavy methylation inactivates DNA but can be reversed if methyl group removed
-methylated DNA often accumulates mutations
-causes permanent inactivation of rarely transcribed genes. |
|
|
Term
|
Definition
-one x chromosome in every somatic cell is inactivated in methylation in female mammals
-lyonization
-males and females have the same number of active x-linked genes |
|
|
Term
|
Definition
| -most hormones are effectors |
|
|
Term
possible modes of hormone action
4 |
|
Definition
-bind directly to enhancer/promoter DNA
-bind to/activate effector
-inactivate reprossor
-change chromatin structure |
|
|
Term
steroid hormones process
5 |
|
Definition
-non polar so they can pass through cell membrane
-binds in cytoplasm to receptor protein (zinc finger motif)
-receptor protien carries hormone into nuveus
-zinc finger binds to HRE (hormone responsive element) DNA acceptor sequence in nucleus
-initiates trascription |
|
|
Term
|
Definition
-proteins with zinc finger motif bind to DNA
-polypeptide folded so zinc is held between two cystines and two histidines |
|
|
Term
Transcriptional gene regulation ENHANCERS
3 |
|
Definition
-region can be up or down stream of promoter/structural genes.
-transcriptional activator binds to enhancer
-DNA loops to form transcription initiation complex |
|
|
Term
Translational gene regulation: MASKED mRNA
2 |
|
Definition
-unfertilized sea urchin eggs store mRNA complexed with protein which inhibits translation.
-after fertilization protein is remoed and traslation increases 50X |
|
|
Term
|
Definition
| a heritable change in the genome (can occure in any DNA sequence but are more likely at "hot spots" within the genome. |
|
|
Term
|
Definition
| occur in gametes and affect the next generation |
|
|
Term
|
Definition
| occur in non-gamatic cells (affects only the single individual) |
|
|
Term
|
Definition
| occur naturally (frequently from errors in DNA replication) |
|
|
Term
|
Definition
| occur from exposure to mutagens (like chemicals and ionizing radiation) |
|
|
Term
effects of germinal mutation
3 |
|
Definition
-albino individuals homozygous for mutant hypostatic allele c
-albino allele prevents expression at pigment loci
-inherited as germinal mutation bia gametes from parents |
|
|
Term
effects of somatic mutation
2 |
|
Definition
-somatic mutation in single cell prevents pigmentation
-cell continues to divede (ex. a gray patch of hair) |
|
|
Term
|
Definition
-rearrangement of section of genome
-change in nucleotide sequence
-change in single nucleotipe pair (point mutation)
-change on one base always results in change in complementary base on opposite DNA strand
-effect of point mutation varies depending on location of change in DNA sequence |
|
|
Term
|
Definition
substitution
transition
transversion
silent
mis-sense
non-sense |
|
|
Term
| substitution point mutation |
|
Definition
| change from one base to another |
|
|
Term
| transition point mutation |
|
Definition
| changes purine (A to G) or pyrimidine (T to C) |
|
|
Term
transversion point mutation
2 |
|
Definition
changes purine to pyrimidine (T to A or C to G)
-less likely to be detected and repaired |
|
|
Term
types of frame shift mutation
3 |
|
Definition
deletion (changing one base for another)
addition (inserting extra base)
-frameshifts have major effects (change all codons downstream) |
|
|
Term
|
Definition
| has no effect on gene function |
|
|
Term
|
Definition
| mutation changes amino acid [GAA(len)--> GGA (pro)] |
|
|
Term
|
Definition
mutation causes premature termination of translation (all down stream amino acids in polypeptide lost)
ATG(tyr)---> ATC(stop) |
|
|
Term
| effects of mis-sense mutation |
|
Definition
| never changes only one base must change the pair. (if it only changes on it is a mutation) |
|
|
Term
|
Definition
-proton moves within thymine or cytosine which changes base pairing.
-loss of NH2 group from base
-converts cytosine to uracil
-also converts adenine to hypoxanthile which pairs with cytosiine |
|
|
Term
Excision repair of DNA lesions
6 |
|
Definition
-mismatched base or distortion in helix recognized by specialized endocucleases.
-come in and take out faulty base and bases on both sides of the faulty one
-eukaryotes remove 28-29
-prokaryotes remove 13
-methyl groups on old DNA strand direct repair to newly-synthesized faulty strand
-DNA pol I and ligase repair gap (but only can do short stretches) |
|
|
Term
Tripple repeat mutation in humans
2 |
|
Definition
fragile X syndrome
huntingsons disease |
|
|
Term
|
Definition
-causes way more repeats in X chromosomes
-causes moderate to sever mental retardation |
|
|
Term
|
Definition
-inherited as autosomal dominant leathle mutation
-trinucleotide repeat (CAG) way more than usual on chromosome 4
-earlier onset with higher number of repeats
-more severe if inherited on perternal chromosome (genetic imprinting) |
|
|
Term
|
Definition
5-bromouracil
ethylmethase sulfonate
proflavin |
|
|
Term
|
Definition
-a base analog that resembles thymine is incorporated into new DNA during replication
-tends to cause teutomeric shift from keto to enol form
-pairs with guanine and induces base substitution |
|
|
Term
|
Definition
-adds alkyl (C2H5) group to guanine
-now pairs with thymine causing substitution. |
|
|
Term
|
Definition
-inserts itself into DNA
-induces frame shift (randomly substitutes a base for the proflavin) |
|
|
Term
Ionizing radiation (UV light)
3 |
|
Definition
-exposure causes bonding between adjacent thymines in DNA (Thymine dimers)
-lesions with missing or incorrect bases from when DNA replicates
-several repair mechanisms in both eukaryotes and prokaryotes |
|
|
Term
pre-replication repair of thymine dimers
2 |
|
Definition
photovariation repair (prokaryotes)
recombination repair (both pro and eukaryotes) |
|
|
Term
|
Definition
| uses visible blue light energy and enzyme photolyase to break dimer and reform A-T pair. |
|
|
Term
|
Definition
-uses A-A from old DNA strand to fill gap in newly synthysized DNA opposite thymine dimer.
-DNA pol I and ligase then replace A-A in old strand |
|
|
Term
|
Definition
high energy short wavelength ionizing radiation break chromosomes and fragment DNA.
-x rays, gamma rays, cosmic rays |
|
|
Term
|
Definition
-"jumping Gene"
-some element moves out of the sequence if there is an activator element that provides transposase.
-some can create repeat sequences in host DNA |
|
|
Term
|
Definition
-copy themselves using RNA intermediate
-HIV virus is an example |
|
|
Term
|
Definition
| variation in number of sets of chromosomes |
|
|
Term
|
Definition
| variation in number of one individual chromosome |
|
|
Term
|
Definition
| -has a number of chromosomes sets that differs from diploid (triploid, tetraploid, ....ect) |
|
|
Term
|
Definition
autopoplyploid
allopolyploid
monoploid |
|
|
Term
|
Definition
| all chromosomes sets from the same species |
|
|
Term
|
Definition
| chromosome sets from different species |
|
|
Term
|
Definition
organism with single set of chromosomes
-male honey bee
-modified meiosis with no chromosome separation |
|
|
Term
how does polyploidy arise
2 |
|
Definition
-spontaneous doubling of chromosome sets from non-disjunction at meiosis
-artificially created using chemicals |
|
|
Term
|
Definition
-missing or extra individual chromosomes
-more harmful than euploid variation as number of gene copies unvalanced
-caused by non-disjunction at meiosis |
|
|
Term
|
Definition
-XXY, XXYY, XXXY
-1 in 400 males
-male phonotype (breast development, testes underdeveloped, low fertility) |
|
|
Term
|
Definition
-Just one X chromosome
-1 in 2500 females
-female phenotype (short, secondary sexual characteristics fail to develop, infertile) |
|
|
Term
|
Definition
-trisomy 13
- heart and skeletal defects
-cleft palate
-90% do not survive infancy |
|
|
Term
|
Definition
-trisomy 18
-severe developmental abnormalities
-death before 1 year old |
|
|
Term
things that cause change in chromosome structure.
6 |
|
Definition
-usually caused by errors diring meiotic recombination.
-high energy ionizing radiation
-deletion
-duplication
-inversions
-translocations |
|
|
Term
commonest cause of chromosome deletion and duplication?
4 |
|
Definition
-misaligned crossover at meiosis
-if homologous chromosomes do not align precisely when synaptonemal complex forms during meiopsis I. Breakage of unequal chromatid fragments occurs.
-they can lead to duplicated segments on a homologous chromosome and a deleted segment on the other
-duplicated and deleted chromosomes are passed on in gametes |
|
|
Term
|
Definition
-chromosome segment missing
-usually deleterious, often fatal in animals, less damaging in plants.
-small deletion may be viable if heterozygous but lethal if homozygous
-Cri Du Chat syndrome (caused by deletion of short arm on chromosome 5) |
|
|
Term
|
Definition
-chromosome segments appear more than once
-typically less damaging than deletion |
|
|
Term
|
Definition
-order of genes reversed on one segment
-looping and twisting when chromosomes pair during meiosis I often results in same inversion on homologous chromosome
-may have little effect
- changed eggplant to tomato |
|
|
Term
|
Definition
-movement or exchange of segments of non homologous chromosomes
-14/21 translocations in humans
-heterozygotes normal but have high risk of having downs syndrome in offspring |
|
|
Term
|
Definition
-study of genetic variation in populations and how it changes over time
-links mendelian genetics with evolution |
|
|
Term
|
Definition
| group of interbreeding individuals living in the same area and sharing the same common areas |
|
|
Term
|
Definition
| relative proportions of different genotypes in a population |
|
|
Term
|
Definition
| all alleles shared by individuals in a population |
|
|
Term
|
Definition
| relative proportions of alleles in gene pool |
|
|
Term
|
Definition
| spatial or temporal patterns of genetic variation within of among population |
|
|
Term
Hardy-Weinberg Assumptions
6 |
|
Definition
-allele frequency in both male and female gametes (no sex linkage)
-population is random mating
-selection is not occurring
-mutation is not occurring
-migration is not occurring
-genetic drift is not occurring |
|
|
Term
|
Definition
| anyone genotype is equally likely to pair with any other genotype in the population |
|
|
Term
| negative assertive mating |
|
Definition
| dissimilar genotypes pair |
|
|
Term
| positive assertive mating |
|
Definition
|
|
Term
|
Definition
-mating pair more closely related than two individuals drawn at random from population.
-increased probability of homozygosity for deleterious alleles (inbreeding depression)
-probability that offspring from first cousin mating has two copies of singel allele identical by descent is 1/16
-closed system |
|
|
Term
effects of inbreeding on population frequencies
3 |
|
Definition
-reduces frequency of heterozygotes
-increases frequency of homozygotes
-inbreeding does NOT affect allele frequencies in gene pool |
|
|
Term
|
Definition
-inbreeding may help remove deleteriouos alleles
-inbred individuals homozygous for deleterious alleles will suffer reduced fitness
-"line breeding" (inbreeding) in animals produce unfit individuals |
|
|
Term
|
Definition
-movement of individuals from one population to another which causes gene flow
-if gene flow occurs between populations with different gene pools, allele frequencies will change. |
|
|
Term
|
Definition
-change in allele frequency due to random gamete sampling
-can have effect on gene pool in small populations
-probability of allele being fixed is the same as its initial frequency
-probability of allele being lost from gene pool is 1-initial frequency |
|
|
Term
|
Definition
-differential reproductive success among genotypes
-principle force altering allele frequencies in large populations |
|
|
Term
|
Definition
stabalizing (intermediate phenotype favored)
directional (one exterem phenotype favored)
disruptive (both extremes favored) |
|
|
Term
|
Definition
| measures contribution of individual genotype to the next generation |
|
|
Term
|
Definition
-getotype in a population with greatest reproductive success assigned a relative fitness number 1
-less successful genotypes assigned lower than 1
-selection coefficient S=(1-RF) [ s measures intesity of selection against genotype |
|
|
Term
|
Definition
-individuals homozygous for a recessive lethal die without reproducing
-RF=0
-S=1
-lethal alleles persist in a population because they dont kill you if you are heterozygous. |
|
|
Term
heterozygote superiority
3 |
|
Definition
-also known as over dominance
-heterozygote has higher RF (relative fitness) than either homozygous
-maintains both allels in the gene pool |
|
|
Term
heterozygote superiority (example)
Sickle cell animia |
|
Definition
-heterozygote has an RF of 1
-they are less severely affected by malaria
-keeps frequency of lethal allel at .2 |
|
|
Term
|
Definition
| applications of population genetics |
|
|
Term
| two types of loss of genetic diversity |
|
Definition
interspecific diversity
intraspecific diversity |
|
|
Term
|
Definition
| different species within an ecosystem |
|
|
Term
intraspecific diversity
3 |
|
Definition
-different genotypes within a species
-defferent alleles within a gene pool
-loss of genetic diversity reduces future chances of species survival |
|
|
Term
why is genetic diversity important?
3 |
|
Definition
-provides buffer against disease/ adverse environmental conditions
-enables population/species to adapt and survive long term environmental changes
-allelic diversity /heterozygosity linked to health and fertility in many species. |
|
|
Term
|
Definition
| autosomal recessive allele causing lethal dwarfism (present in 9% of condor gene pool) |
|
|
Term
|
Definition
-small populations are at a greater risk of extinction, and are more likely to lose genetic diversity
- the longer a pop. is in a bottleneck the more diversity you will loose to genetic drift |
|
|
Term
Effective population size (Ne)
2 |
|
Definition
-(Ne) is the number of individuals in population having equal probability of contributing gametes to the next generation.
-(Ne) is almost always smaller than N because some individuals are infertile, too young or too old. |
|
|
Term
bottlenecked populations
2 |
|
Definition
-a population that goes through a sever reduction in size and then recovers
-often have greatly reduced genetic diversity |
|
|
Term
|
Definition
| midochondial DNA fingerprint |
|
|
Term
|
Definition
| may cause loss of valuable alleles from gene pool |
|
|
Term
|
Definition
| may reduce overall fitness and survival / reproduction rates |
|
|
Term
|
Definition
| caused by population fragmentation |
|
|
Term
|
Definition
-use gene banks
-captive breeding |
|
|
Term
|
Definition
-population augmentation (increase)
-habitat preservation |
|
|
Term
|
Definition
-results from mutation
-transformation of noral cells to malignant cells
-uncontrolled cell division
-migration of malignant cell to other sites
-tumors derived from repeated division of an individual transformed cell |
|
|
Term
|
Definition
| uncontrolled cell division |
|
|
Term
|
Definition
| migration of malignant cell to other sites |
|
|
Term
|
Definition
-limited lifespan in culture(lose telomeres and stop dividing)
-need to attach to hard surface in culture
-stop dividing if crowded
-genetically stable
-maintain cell characteristics |
|
|
Term
|
Definition
-"Immortal" (divide indefinitely)
-can divide in suspension
-keep dividing even if crowded
-genetically unstable (high rates of mutation and aneuploidy)
-loose cell characteristics |
|
|
Term
genetic events leading to cell trasformation
2 |
|
Definition
-malignant cells result of mutation in key genes
-cancer may result from multiple mutations (Colon cancer) or from singe-gene mutations |
|
|
Term
key mutations that cause cancer
2 |
|
Definition
-inactivation of tumor suppressor genes
-activation of proto-oncogenes (normal cell that mutates) |
|
|
Term
|
Definition
-codes for pRB protien
-binds to E2F transctiption falter preventing G1/S transition in cell cycle |
|
|
Term
|
Definition
Involved in:
-DNA repair
-Cell cycle arrest
-Apoptosis |
|
|
Term
|
Definition
-binds to and transports GTP
-mutation causes it to stay on and keep using GTP
-this causes continuous growth of cells |
|
|
Term
|
Definition
-APC gene in chromosome 5 is lost (causes increased cell growth)
-DNA loses methyl group (causes Adenoma I which is benign)
-ras gene mutates (causes adenoma II which is benign)
-DCC in chromosome 18 lost (causes adenoma III which is benign)
-p53 in chromosome 17 lost (causes carcinoma which is malignant tumor) |
|
|
Term
|
Definition
| source of cells which were cultured to create an imortal cell line (HeLa cell line) |
|
|
