linkage and mapping

Question 1

genetic linkage

Answer 1

DNA sequences that are close together on a chromosome to be inherited together during meiosis phase of sexual reproduction

Question 2

which of the following defines genetic linkage?
A. two or more genes that are physically connected on a chromosome
B. genes that are transmitted to the next generation as a group
C. process by which genetic information is exchanged between homologous chromosomes
D. A and B

Answer 2

two or more genes that are physically connected on a chromosome and genes that are transmitted to the next generation as a group

Question 3

linkage group

Answer 3

2 or more genes that do not independently assort and tend to be transmitted together

Question 4

which of the following best describes a linkage group

Answer 4

a chromosome

Question 5

Assume that genes F and G are located on the same chromosome. On one chromosome alleles F and G are found, while the homologue contains alleles f and g. Which of the following would be an example of a recombination event?
A. alleles F and G together on one chromosome
B. alleles f and g together on one chromosome
C. alleles F and g together on one chromosome
D. alleles f and G together on one chromosome
E. C and D

Answer 5

alleles F and g together on one chromosome and alleles f and G together on one chromosome

Question 6

which of the following is a statistical test used to determine if 2 genes are linked or assorting independently

Answer 6

chi-square test- used to determine if the outcome of a cross is consistent with linkage or with independent assortment

Question 7

while mapping 2 genes in Drosophila, you observe 30 recombinants among 200 total offspring. What is the distance between these genes?

Answer 7

15 map units

Question 8

map distance formula

Answer 8

(# of recombinant offspring/ total # of offspring) x 100

Question 9

a map distance between genes indicates which if the following

Answer 9

23.6% of the offspring exhibit recombination between 2 genes

Question 10

in a mapping experiment, which phenotype should occur most often in the F2 offspring

Answer 10

parental phenotypes as they are the most frequent

Question 11

crossover

Answer 11

single cell divides twice to produce 4 cells containing 1/2 the original amount

Question 12

a crossover in meiosis is na exchange of genetic material between

Answer 12

non-sister chromatids of homologous chromosomes

Question 13

synteny

Answer 13

physical linkage of genes into the same chromosomee

Question 14

the number of linkage groups=

Answer 14

the number of types of chromosomes of the species

Question 15

likehood of crossing over depends on

Answer 15

it depends on the distance between the two genes

Question 16

chi square analysis

Answer 16

method used to determine the outcome of a cross is consistent with linkage or with independent assortment

Question 17

recombination

Answer 17

physical change of the DNA from one chromosome to the other

Question 18

genetic mapping

Answer 18

purpose is to determine the linear order of linked genes along the same chromosome

Question 19

which crosses involving linked genes occur less frequently

Answer 19

double crossover

Question 20

double crossover

Answer 20

separate the gene in the middle from the other two genes at either end

Question 21

genome

Answer 21

haploid set of chromosomes

Question 22

recombination

Answer 22

exchange of genetic material between different organisms which lead to production of offspring with combinations of traits that differ from those found in either parent

Question 23

crossover

Answer 23

swapping of genetic material that occurs in the germ line