Chapter 7 Handout

what is segregation

what is segregation

partitioning of genetic material into two daughter cells

law of independent assortment

states that random orientation of homologous chromosome pairs during metaphase I allow for the production of gametes with diff assortments of homologous chromosomes

linked genes

the principle that genes that are physically close to eachother on a chromosome tend to not get separated in meiosis and recombine

what happens to genes in linkage

genes/alleles that are physically close on the chromosome are inherited together

if two genes are on the same chromosome, and crossing over doesnt occur, what is the recombination frequency?

0%

when is there complete linkage between genes?

when there is no crossing over between them and recombination is 0%

in meiosis, how many genetically different gametes does complete linkage produce

two

if two genes are on different chromosomes, or the same and the recombination frequency is 50% what does this mean

they are not linked

if recombination frequency is 0%

it is complete linkage

if recombination frequency is 10%

it is linkage

if recombination frequency is 50%

it is no linkage

if recombination frequency is 20%

it is linkage

genes that are inherited as a group are termed as what

a linkage group

what did morgan postulate

that genes exist in a linear order on the chromosome

how is the distance of genes from eachother calculated

recombination frequencies

how is the distance between chromosome positions measured?

map units (mu), genetic map unit (gmu), or centimorgan (cM)

1 mu = 1 gmu = 1 cM = % recombination frequency btwn genes

gene mapping refers to the process of determining the what of genes on chromosomes

location

single crossover is for what

determining the distance between two linked genes

double crossovers determine the distance and what of genes

distance and order between genes

what is the double crossover frequency if the single crossover frequency is 20% and 30%

6%

what is the double crossover frequency if the single crossover frequency is 2% and 3%

.06%