Exam 1 Flashcards
Identify and describe the 6 model organisms used in Genetics
- fruit fly (drosophila)
- E coli
- caenorhabditis (roundworm)
- arabidopsis (thale-cress plant)
- musculus (house mouse)
- bakers yeast
Understand and be able to explain the 11 fundamental concepts of Genetics
- cells are two basic types (eukaryotic and prokaryotic)
- the gene is the fundamental unit of heredity
- genes come in multiple forms called alleles
- genes confer phenotypes
- genetic info is carried in DNA and RNA
- genes are located on the chromosomes
- chromosomes separate through the process of mitosis and meiosis
- genetic info is transferred from DNA to RNA to protein
- mutations are permanent changes in genetic info that can be passed from cell to cell or from parent to offspring
- many traits are affected by multiple factors
- evolution is genetic change
Mendel’s law of segregation
each individual organism possess two alleles encoding a trait (parental and maternal)
mendels law of independent assortment
alleles at different loci separate independently of one another
multiplication rule
the probability of two or more independent events taking place
- ex: the probability of having two boys (.5*.5)
addition rule
probability of any two or more mutually exclusive events taking place
- ex: probability of the offspring being heterozygous or homozygous dominant in two heterzygote cross
what is binomial data
only two possible outcomes for a given trait
- like boy or girl, yes or no
P= (n!/s!t!)p^sp^t
chi-square goodness of fit test is used for
evaluate the role of chance in producing deviations between observed and expected
Chi-sqaure goodness of fit formula
x^2= [(ovs-exp)^2/ exp] + same
is the p is low…
you reject the Ho
p value has to be lower than 0.05
extrinsic or intrinsic
extrinsic: set of expected frequencies that are determines completely outside the data, based on prior knowledge
intrinsic: uses information directly calculated from the data itself to determine the expected frequencies, often estimation
general sexual reproductive process
zygote (sex cell) undergoes meiosis creating 4 haploid gametes
gametes are fertilized (sperm and egg) which created a zygote
monoecious
organism that bear both male and female reproductive structures
- like some plants
diecious
individual organism has either male or female reproductive structures
- like humans
hermaphroditism
both sexes are present in the same organism
sex chromosome vs autosome
sex: determine the sex
autosome: any other chromosome that doesn’t determine sex
hetero vs homo-gametic sex
hetero: produces two different types of gametes with respect to the sex chromosome
- male humans: XY
homo: produces gametes that are all the same
- female humans: XX
common sex-determination systems
XX(F)-XO(M): some grasshoppers and other insects
XX(F)-XY(M): insects, fishes, amphibians, reptiles, mammals
ZZ(M)-ZW(F): butterflies, birds, some reptiles/amphibians
genic sex determination
no distinct sex chromosomes
- plants, fungi, protozoans, and fishes
chromosomes complements and sexual phenotypes in drosophila
XX is female while XO is male, they lack another X or Y chromosome
environmental sex determination
environment controls the sex
- turtles, alligators, and some invertebrates
turner syndrome
females who have underdeveloped secondary sex characteristics
-XO
klinefelter syndrome
males who have one or more Y chromosomes and multiple X chromosomes
- XXXY, XXXXY, XXYY
poly-x females
females who possess three X chromosomes
-XXX
XYY-Males
no distinctive physical characteristics other thank to be really tall, learning difficulties
Androgen insensitivity syndrome
females who have exterior female characteristics but lack internal structures
- instead have testes that produce testosterone
- but androgen receptor is deficient that doesn’t respond to testosterone
what causes “male-ness” in humans
the sex determining Y gene (SRY)
dosage compensation
mechanisms to equalize the amounts of protein produced by the single X and by two autosomes in the heterogametic sex
barr bodies, how many are there, how do they relate to tortoiseshell cats
- condensed, darkly staining bodies in the nuclei of cells
- # of X left over after 1 stays active: XXXY -> 2 X’s are barr bodies
- the X inactivation shows the different color patches
Lyon hypothesis
barr body was an inactive X chromosome
additive alleles vs non-additive effects of alleles
additive: each allele accumulates in an regular way
non-additive: each allele accumulates in an irregular way
Charlie Chaplin case
had a completely different blood type than the baby (couldn’t have given a blood type that he didn’t have)
- had to take care of the baby
complete vs incomplete penetrance
complete: all cells are effected in a way
incomplete: only some cells are effected
narrow vs broad expressivity
narrow: when penetrated they do not have a wide range, black or white
expressivity: when penetrated there is shades in between
epistasis
when more than one locus influences a trait
epistatic vs hypostatic gene
epistatic: gene that mask the other gene
hypostatic: gene that is being masked
