Bio day 10 Flashcards
an organism’s observable traits (determined by genotype and enbrironment)
phenotype
genotype
the genetic makeup responsibile for a particular train
genetic material coding for a single gene product(peptide, rRNA, tRNA)
gene
the chromosomal location of a gene
locus
one variant of a gene
allele
chromosomes that code for the same set of genees, may be different alleles though(one from each parent)
homologous chromosomes
having tow identical alleles for a gene
homozygous
having two different alleles for a gene
heterozygous
the normal or most prebalent allel in a population
wild type
an allele where only one copy is necessary to yield the corresponding phenotype
dominant
an allele where two copies are necessary to yeild the corresponding phenotype
recessive
when a heterozygote has the pheotype of only 1 of the alleles ( the dominant one)
complete dominance
both inherited alleles are complelty expressed (ex. blood type)
codominance
phenotypes of the progeny that are intermediate of the parental phenotypes(snap dragons- homozygous red crossed with homozygous white gives pink)
incomplete dominance
when a loss of function mutation doesnt result in complete lack of a phenotype
leakage
the percentage of organisms having a certain genotype expressing a certain phenotype
penetrance
a term describing the variation in phenotpye amoung organims with a given genotype
expressivity
whan a single gene affects multiple traits
pleiotropism
when multiple genes affect a single trait
polygenism
when the expression of a gene is dependent upon another gene
epistatsis
the set of all alleles in a population
gene pool
interphase…meiosis 1… meiosis 2
diploidXX… haploidX…. haploid L.L…
G1 Protein and nucleic acid synthesis to prepare for replications producation of organelles
interphase
S DNA replication
Interphase
Recombination happens in…
Prophase I
longest phase, chromosemes condense and tetra fomraiton (homologous pairs), disappearance of the nuclear envelope and polarization of the centrioles (MTOC’s)
Prophase I
Chromosomes line up on the metaphase plate, spindle fibers attach at centromeres via kinetochores
metaphase I
spindle fibers PULL HOMOLOGOUS CHROMOSOMES APART towards the centrioles… clevage furrow beings forming
Anaphase 1
nuclear membranes reform, completion of cytokinesis
telephase i
chromosemes condense, disappearance of the nuclear envelope and polarization of the centrioles
Prophase II
chromoseomes line up on metaphase plate, spindle fibers attach at centromeres via kinetochores
metaphase II
spindle fibers PULL SISTER CHROMATIDS APART towards the centrioles, cleavage furrow begins forming
anaphase II
nuclear membranes reform, completino of cytokinesis
telephase II
failure of tetrads to separate during meiosis I or sister chromatids in meiosis II….. Down syndrom, turner syndrome, Kleinfelter syndrome
nondisjuction
movement of a segment of one chromosome to another non-homologous chromosomes
translocation
separation of alleles into haploid gametes
law of segregation
genes assort independently to the progeny
law of independent assortment
leads to new cobinations of alleles, occurs during prophase 1 of meiosis, exchange of segments from homolougous chromosomes
recombination
genes on the same chromosome won’t necessarily undergo independent assortment, the closer together on the chromosome the greater the linkage btw genes, the likelihood of recombination occurring btw two genes increase with the distance in teh genes
linkes genes
ofspring (female) have only a single X chromomes resulting from nondisjunction
Turner Syndrome(X)
offspring(male) XXY have an extra X crhomosome resulting from nondisjunction
kleinfelter
any genetic disorders coded by the mitochondrial DNA will be passed on to all offspring
mitochondrial inheritance… only mother.
mutations
most mutations are deleterious to the cell…. translational, transcriptional errors
a single base substitution
point mutation
point mutation leading to a codon coding for a different amino acid
missense mutation
point muattion leading to a premature stop codon
nonsense mutation
insertion or deletion leading to a change in teh reading frame of a gene
frameshift muations
low level of natural mutations that occur during replication.. random error
mutations in replication
metabolic disorders caused by muations
inborn errors fo metabolism
an agent that causes mutations
mutagen
an agent that can cause cancer
carcinogen
allele frequenceies remain constatn in a gene pool for a population in equilibrium
hardy weinberg equilibrium
hardy weinburg equilibrium
p+q=1
equation hardy
p^2+2pq+q^2=1
assumptions for equilbirium
- Random Mating
- No mutations
- No selection ( natural or otherwise)
- No migration
- Large population size… no genetic drift
the ability of an organism to pass on its alleles
fitness
differential reporduction of an organism based upon fitness in its environment… the alleles that confer firtness will increase in frequency in the gene pool over time
natural selection
selection against the extremes.. for the averages
stabilizing selection
selection against teh avgs
disruptive (divergent) selection
selection against one extreme (but favoring the opposite extreme)
directional selection
directional selection done by humnas with selecting for traits in animals and crops
artificial selection
differential mating btw males and females
sexual selection
group of organsims that are capable of interbreeding to produce fit offspring
species
barrieres preventing members of different species from producing fit offspring
reproductive isolation
the existence of multiple phenotypes within a population
polymorphism
an inherited trait that confers greater fitness
adaptation
an adaptation to a specific function or environment
specialiization
the sum of the environmental requiremnts required for a species to persist, includes habitat, predators, prey, thought of as being unique for each species
ecological niche
increased likelihood of mating btw organisms w similar genotypes
inbreeding
increased likelihood of mating btw organism w different genotypes
outbreeding
random change in allel frquencies in a population, smaller populaitons are more suseptible to it…
genetic shift
dramatic decrease in size of a population making it suseptible to genetic drift
bottleneck
two species possess the same analogous structures unrealated to a common ancestor
convergaent evolution
divergence leading to distinct populations/species
divergent evolution
similar evolutionary changes in different species due to similar environmental pressures
parallel evolution
when a species requres another species as a host to live, harming the host in the process
parasitism
an organism requres another species as a host to live w no harm or benefit to the host
commernsalism
symbiotic relationship btw two organisms that confers fitness to both
mutualism
similarities in stages of develoment
ontogeny
ontogeny can be used to determine evolutionary relationships btw organisms
phylogeny
life was seeded extraterrestrially (meteors, cosmic dust,….)
panspermia
Miller-urey experiments
organic molecules can be produces form a simple mexture of gases and electricity… formeldehyde, urea, and other result
lipid bylayers
spontaneously form in aqueous solution via self assembly
orignial gentic material
RNA
What attributes do we associate with life?
- heredity and reproduction
- being distince from its environment
- capable of growth and development
- the ability to respond to stimuli from the environment
- capable of homeostasis and regulation
