Lecture 1-2 Flashcards
A genetic factor that helps determine characteristics is a…
gene
Two or more alternate forms of a gene are called…
alleles
What is the location on a chromosome occupied by an allele
locus
A specific set of alleles possessed by an organism is the organisms…
genotype
What is the term for an organism that carries two different alleles at a locus
heterozygote
What is the term for an organism that carries two of the same alleles at a locus
homozygote
What is the visual manifestation of characteristics
phenotype/trait
Who discovered the basic principles of heredity
Mendel
What did Mendel use in his study
pea plants
What was the general consensus of Mendels study
Taking one homozygous dominant parent and one homozygous recessive parent produces a heterozygous F1 product, however when the F1 plant self reproduces, 1/4 homozygous dominant, 1/2 heterozygous, and 1/4 homozygous recessive products are formed
What is the ratio in F1 heterozygous self reproduction
9:3:3:1
What is non-disjunction
When an error in cell division occurs and one daughter cell holds two sister chromatids and one daughter cell lacks a chromatid
What is the common result of recessive gene mutations
loss of gene function
What is a null/amorphic allele
a recessive mutation where either a non-functional protein is produced or no protein is produced at all (overall; no function)
What is a hypomorphic allele
a recessive mutation where a poorly functioning protein is produced or reduced amounts of a normally functioning protein are produced (overall; less function)
What is the “and” rule in terms of fractions
multiply the fractions
(ie. rolling a dice has a 1/6 chance of rolling a 4, so if you roll the dice twice what are the odds you’ll role a 4 on the first AND second roll; 1/6 x 1/6 = 1/36)
What is the “or” rule in terms of fractions
add the fractions
(ie. rolling a dice has a 1/6 chance of rolling a 4 or a 1/6 chance of rolling a 3, what are the odds you roll a 3 OR a 4; 1/6 + 1/6 = 1/3)
What is the common result of a dominant gene mutation
a gain/change in gene function
What is a dominant hypermorphic allele
over-production of protein or increased activity levels of proteins - resulting in negative phenotypic consequences
What is a neomorphic allele
protein present that has a new function, or when the altered protein has negative impacts on the wild type - resulting in negative phenotypic consequences
For traits that are rare and dominant, are affected individuals more likely to be homozygous or heterozygous and why
heterozygous - if the trait is RARE, then the dominant allele is rare in the population, and breeding between two heterozygotes to achieve a homozygous dominant product would be very rare since most do not carry the dominant allele to begin with
Practice the take home problem at the end of lectures 1-2 slides (answer on back of card)
1/6 chance of having an albino child
