PUNNETT SQUARE Flashcards
Punnett square is developed by _________ to describe the possible genetic combinations of a certain breeding experiment
Reginal Punnett
Device use to examine the genotypical outcome probabilities of an offspring
Punnett Square
heterozygous brown crossed with dad homozygous white
Mom
Genes and alleles are segregated from each other
Law of Segregation of Mendel
Controlled genes or traits crosses
Breeding experiment
homozygous parents
P generation
hybrids
F1 generation
A genetic cross involving a single pair of genes (one trait)
Monohybrid cross
allele for tall (dominant)
T
Allele for dwarf (recessive)
t
homozygous tall plant
TT
homozygous dwarf plant
tt
parentals true breeding, homozygous plants
P
ratio of possible gene combinations
Genotypic ratio
possible phenotypes expressed by offspring
Phenotypic ratio
self-fertilize F1 generation
F2 generation
9:3:3:1
Phenotypic Ratio
copying DNA to be passed down from parent cell to daughter
Replication
variation of gene
Allele
_________ is a protein coded by the Ras gene
Ras mutation
a mutation whose gene product negatively affects the biochemical activity of the normal product within the same cell
Dominant negative
A mutation that confers new or enhanced activity on a protein
Gain of function
Dominant alleles usually code for proteins that are expressed
Simple dominance
always and absolutely active throughout cell cycle
Consecutively active
The dominant alleles are both expressed, but they are segregated from each other in which areas they are expressed
Codominance
The dominant allele does not completely mask the effects of the recessive allele
Incomplete dominance
Interaction of nonallelic genes in the formation of the phenotype
EPISTASIS
different location in the chromosome
Nonallelic genes
gene that can affect the expression of another gene
Epistatic
Occurs when the recessive allele of one gene masks the
effects of either allele of the second gene
Recessive Epistasis
also known as Duplicate Gene Action
Duplicate Dominant Epistasis
Also known as Complementary Gene Action
Duplicate Recessive Epistasis
The presence of both the dominant alleles of different gene
loci forms a new phenotype
Duplicate Genes with Cumulative Effect
Also known as Dominant Inhibitory Epistasis
Dominant Recessive Interaction
Easiest type of Punnett square
MONOHYBRID CROSS
Mating that involve parents that differ in two genes independent traits
Dihybrid Crosses
Copying DNA to be passed down from parent parent cell to daughter
REPLICATION
Is the key to life; makes living possible
CENTRAL DOGMA
Variation of gene
ALLELE
Usually do not code for proteins
RECESSIVE ALLELES