Genetics Flashcards
(27 cards)
True-breeding/homozygous
individuals that have same alleles for gene
Allele
Different versions of DNA sequence at a given genomic location
Heterozygous
individuals that have 2 different alles for a gene
Genotype
total set of alleles that an individual has
Phenotype
expression pattern of alleles
Mutually exclusive
Both events cannot happen at the same time
Independent events
knowing one event occured does not change probability of other event
Rule of addition
for 2 mutually exclusive events, probability of either event occuring is sume of individual probabilities
Rule of multiplication/ Product rule
probability of 2 independent events both occurs is product of individual probabilites
Pleiotrophy
single gene affects more than one trait, allel has more than 1 effect on phenotype
Incomplete dominance
heterzygote is intermediate, white flower + red flower produce pink flower
Codominance
no single allele is dominant, heterozygote shows aspect of both homozygotes. Calico cat
Phenotypic plasticity
production of different phenotypes for same genotype due to environmental conditions
Continuous variation
Variation in trait occurs along continuum, ex: height. Occurs when trait is determined by >1 genes
Epistasis
interaction of genes that are not alleles, where one modifies phenotypic expression of other. ex: suppression of the effect of one such gene by another.
SRY gene
encodes protein involved in primary sex determination, if SRY protein is present embryo develops testes
Dosage compensation
One X chromosome in females is inactivated early in embryonic development, ensures equal level of expression from sex chromosomes in males and females
Maternal inheritance
uniparental inheritance from mother, males and females are equally affected. Organelles usually inherited from mother
Epigenetic inheritance
cell-to-cell and organism-to-organism inheritance of trait that doesn’t involve alterations to DNA, mediated by changes in chromatin structure that dont alter DNA itself
Epigenetic change
mitotically and/or meiotically stbale change in gene function that doesnt involve change in DNA sequence
Recombinant gametes
formed by recombining parental alleles, created through crossing over
Linked genes
Genes that are close together on same chromosome, typically transmitted as a unit
Locus
specific position on chromosome where particular gene is located
Pedigree
Squares are male
Circles are female
Colored are affected by trait
