Molecular Genetics Exam 4 Flashcards
Chromosome linkage is based on
linkage
The position of a gene on a chromosome is known as a
loci
The loci can be determined based on its
distance and ability to recombine with other genes
Genes assort independently if they are on different
chromosomes
Independent assortment
non homologous chromosomes orient independently at metaphase 1 of meiosis
when genes are on the same chromosome, genes are linked because of __ not the ___
chromosome, gene
what is the unit of transmission during meiosis for gene linkage?
chromosomes
Crossing over results in
recombinants
parental are the products that look like the
parents
Crossing over occurs during
prophase 1 of meiosis
crossing over is an __ exchange of __ material
equal, genetic
synapsed chromosomes in meiosis wrap around each other to create
chiasmata
chiasmata are
x shaped intersection points of genetic exchange
if crossing over occurs between 2 linked genes, both __ and __ gametes are produced
parental (non recombinant) abd recombinant (crossover)
Gene distance is called
map units
map units are equal to the
percent recombination which suggests how far apart genes are on the chromosome
Despite how far away genes are, they will never get more than
50% recombination
The further away the recombination, the __ of recombination
greater chance
How to create map units
(total number of recombinants/total number of progeny)*100
The lowest numbers for progeny represent
recombinants
if 2 crossovers take place between marker genes, and both involve the same pair of chromatids, then neither crossover is detected because
all of the resulting chromosomes are nonrecombinant
DNA markers
short segments of DNA whose sequence and location are known
Represent landmarks along the chromosome
Single nucleotide polymorphism is a
molecular marker that can determine cancer
Restriction fragment length polymorphisms(RFLPs)
polymorphic sights that are specific DNA sequences that are recognized and cut by restriction enzymes
