Mendelian Genetics -- Lecture 10 Flashcards
genetics (definition)
study of heredity and the variation of inherited characteristics
Gregor Mendel
founder of modern science of genetics
Mendel studied ___ in pea plants
inherited traits
Mendel studied inherited traits in ___
garden pea plants (possum sativum)
importance of Mendel:
ideas about inheritance before Mendel:
not quantitative
‘blending of inheritance’ (offspring’s traits are a blend of parents’ traits)
importance of Mendel:
Mendel took a ___ approach to studying inheritance
quantitative
importance of Mendel:
Mendel hypothesized a ___ –> genes
particulate unit of inheritance
importance of Mendel:
Mendel hypothesized a ‘particulate’ unit of inheritance –> ___
genes
important terminology:
gene (definition)
a portion of DNA, w/in a chromosome, that contains the information necessary to specify or influence a trait
important terminology:
polygenic (definition)
multiple genes may govern 1 trait
important terminology:
chromosome (definition)
a unit of DNA that contains many genes
important terminology:
locus of a gene (definition)
physical location (address) of a gene on a chromosome
important terminology:
remember diploids have ___ copies of each chromosome
2
important terminology:
remember ___ have 2 copies of each chromosome
diploids
important terminology:
so diploids have ___ copies of each gene
2
important terminology:
so ___ have 2 copies of each gene
diploids
important terminology:
there are ___ versions of each gene
different
important terminology:
allele (definition)
each version of a gene
important terminology:
if allele on each chromosome is the same
homozygous
important terminology:
homozygous…
if allele on each chromosome is the same
important terminology:
if allele on each chromosome is different
heterozygous
important terminology:
heterozygous…
if allele on each chromosome is different
important terminology:
an individual will be ___ for some alleles and ___ for others
homozygous
heterozygous
important terminology:
genotype (definition)
particular set of alleles carried by an individual
important terminology:
phenotype (definition)
physical trait resulting from a particular genotype
important terminology:
different genotypes can have the ___ phenotype
same
important experimental terminology:
true-breeding organisms (definition)
organisms that always show a particular phenotype in every generation
important experimental terminology:
parental generation (P0)
parents in original cross
important experimental terminology:
1st filial generation (F1)
offspring of parental generation
important experimental terminology:
2nd filial generation (F2)
offspring of 1st filial generation
important experimental terminology:
Mendel’s experiments used:
monohybrid crosses
dihybrid crosses
important experimental terminology:
monohybrid crosses (what are they and example)
parents that are only different in 1 trait
ex. RR vs. rr
important experimental terminology:
dihybrid crosses
parents that only are different in 2 traits
ex. RRYY vs. rryy
example of 1-trait cross (monohybrid cross)
crossed true-breeding round pea plants w/ true-breeding wrinkled pea plants
Mendel’s Law of Dominance
1 allele/phenotype is dominant over the recessive allele/phenotype
dominant and recessive:
recessive phenotype
phenotype not observed in the F1 generation
dominant and recessive:
dominant phenotype
phenotype that is observed in the F1 generation
dominant and recessive:
dominant allele
allele that gives rise to the dominant phenotype
dominant and recessive:
recessive allele
allele that gives rise to the recessive phenotype
phenotypic ratio in F1 cross
3/4 : 1/4
3 : 1
