Tutoring Flashcards
telomere
end of chromosome
get shorter every replication-why we age
evenually can’t replicate well
chromsome can be single or
two sister chromatids
both have centrosomes
certain cancers have more
telomerase (redoes telomeres) and can proliferate faster without loss of telomeres
metacentric, submetacentric, telocentric, acrocentric
placement of centromeres, review photos
genotype
what gene do you have
heterozygous and homozygous
complete dominant, co dominance (spotts), incomplete dominance (pink flowers)
phenotype
what gene is expressed (what do you look like)
each chromosome has a p and q arm
44 autosomes (22 pairs)
x y
karyotype is 46XX, XY
location of specific gene 12q15.2 (chrom arm, subband, band) or size, banding pattern, centrosome position
lyonization inactivation of one x chromsomes (can be mosaic)
barr body-inactivated x
mosaicism
-different cells have different genotypes
pleiotropy
one gene effects 2 or more phenotypes
variable expresicvity
genotype can present differently in different people
penetrance
geneotype doesn’t equal phenotype
anticipation
huntington’s gets worse each generation
locus of hterogenity
many genotypes, one phenotype
x linked dominant males transmit to females
100% of the time
females transmit to all children 50% of the time
x linked recessive
mother to son trait normally
affected fathers make carrier daughters
colorblindness
heteroplasmu
certain number of mt mutations before dz presentation
homologous recomination same thing as
crossing over
what makes the differences between siblings
also random segregation (chromosomes separate into different cells)
translocation
reciprocal exchange of material betwen two chromosomes
robertsonian-translocation only between acrocentric chromosomes (13, 14, 15, 21, 22) result in extra chromosome (pataeu and downsyndrome)
will result in trisomies and monosomies
genomic imprinting
normal, one allele is turned off via methylation
example is 15q11-13 prader willi/angelman
uniparental disomy
2 copies of same chromosome from 1 parent
can also cause PW/angelman
gene frequency
proportion of each genotype in population (p2, q2, 2Pq)
allele frequency
proportion of allele in population (p and q)
know central dogma
replication, transcription, translatino, reverse tarnscription
DNA
ds and antiparelle, sugar phosphate backbone is negatively charged, 10b per turn, two H for AT, 3H for GC
histones epigenetics
octamer protein, lots of Luys and arg. + charge
- DNA wraps around Histones with H bonds
modifications of histones tells DNA what form to be in
acetlation with HATs
activates DNA
deacytlation with HDACs
deactivates DNA
methylation of DNa
deactivates DNA
methylation of histones
can activate or deactivate
DNA methylation done by
methyl transferases (INHIBIT/deactivates)
happens in promoters rich in CG islands
assocaited with genomic imprinting (inactivate one copy of a gene)
lyoniazation (inactivate chromosome X)
aging
carcinogenesis
one histone and 146 bp DNA make
nucleosome
many nucleosomes in line make chromatin
heterochromatin tight, not active
euchromatin light actve
copy number vairaitions
makes us different (ethinc)