anaxagoras
greek philosopher who helped form ideas (with Aristotle and Hippocrates) about pan genesis
gemmules
form" provided by male in pan genesis, while female provided raw material
preformationism
spermatists vs ovists
epigenesis
shows baby growing from embryo to fetus
linkage group
each kind of "n" from a different parent
euchromatin
active part of chromatin (loosely coiled)
heterochromatin
coiled piece of inactive chromatin
metacentric, acrocentric, telocentric
refers to placement of the centromere on the homologs
satellites
nucleolus, where rna synthesis occurs
mitosis (# of dna molecules)
4 4 4 4 2
mitosis (# of chromosomes)
2 2 4 4 2
meiosis I (# of dna molecules)
4 4 4 4 2
meiosis I (# of chromosomes)
2 2 2 2 1
meiosis II (# of dna molecules)
2 2 2 2 1
meiosis II (# of chromosomes)
1 1 2 2
cell cycle
g0, g1, s, g2, p, m, a, t, c
which takes longest?
g1 phase
g1-s checkpoint
size of cell, time, triggers mitogens
g2-m checkpoint
repairs and completes replication
prophase summary
preparation phase (longest)
metaphase summary
chromosomes move to equator
anaphase summary
centromeres divide and chromosome number doubles
telophase summary
reverse of prophase, begins cytokinesis
prophase specific
chromosomes condense, nuclear membrane dissipates, spindle forms
metaphase specific
chromosomes move to equator and are attached to their spindles are the centromere
anaphase specific
centromeres divide and each sister chromatid is pulled to an opposite side
telophase specific
spindle breaks down, nuclear membranes form, chromosomes uncoil, cytokinesis
cytokinesis
cleavage of a cell using a contracting ring of microfilaments
plant cell division
vesicles deliver material to form a new cell plate
bivalent
(formed by prophase) 2 2-stranded chromosome paired closely together so basically a pair of homologous chromosomes so the cell can tell each linkage group apart
synoptical complex
...
leptotene
chromosomes condense
zygotene
synapsis begins
pachytene
crossing over occurs
diplotene
synaptical complex disassociates, chiasma
diokinesis
prophase ends, spindle forms
chiasma
point of contact between chromatids while they are in pairs
segregation vs independent assortment
segregation of genes always occurs but independent assortment does not
segregation
alleles separate during the first meiotic division
independent assortment
unlinked alleles separate randomly
mono/di/tri hybrid crosses
heterozygous with homozygous recessive (to determine if one is heterozygous or homozygous dominant)
dihybrid phenotypic ration
9:3:3:1
dihybrid genotypic ration
1:2:1:2:4:2:1:2:1
incomplete codominance
blends to make a new allele
types of problems: possibility this event will occur?
multiply fractions
types of problems: possibility this mother will produce this gamete?
multiply fractions
polymorphism
variation in a gene pool where variation is less than 99%
epistasis
when one gene hides the expression of a seemingly unrelated one
dominant epistasis
12:3:1 (focus on 12)
recessive epistasis
12:3:4 (focus on 4)
both dominants needed
9:7 (focus on 9)
both recessives needed
15:1 (focus on 1)
haplotype
haploid genotype
problem type: is the male the father
use the baby's genotype to attribute the likely genotype of mother, then see if remainder matches with father
histocompatibility loci
paternity test conductors
problem types: penetrance
multiply penetrance (example: 7/10) by other fraction of probability
codominance
products of both alleles are seen
pleiotropy
when a single gene affects multiple traits (example: agouti mice)
recessive lethal
a mutation that is lethal so it impacts the phenotype
dominant in pedigree
won't skip a generation
sex-linked in pedigree
cannot be passed from father to son
sex-linkage
a gene on the x chromosome (example: hemophilia)
sex-limited
on any chromosome, but phenotype only shows in one (example: breast development)
sex-influenced
trait more common on one of the sexes (example: beard growth)
pedigree diamond
sex unspecified
pedigree target sign
carrier of x-linked reccessive
crossed out sign pedigree
death
pedigree droplet
abortion or stillbirth
pedigree arrow
proposiatus/proposita/proband
pedigree double link
consanguineous marriage
problem type: pedigrees
multiply the probability of traits being passed on (and remember to include the final one)