Chapter 7

Question 1

Principle of segregation:

Answer 1

Alleles separate during
meiosis (one allele passed into each gamete)

Question 2

Independent assortment

Answer 2

Alleles at one locus sort
independently from alleles at another locus

Question 3

Independent separation of alleles results in
Recombination

Answer 3

Alleles sort into new combinations

Question 4

Crossing over results in recombination:

Answer 4

it breaks up the associations
of genes that are close together on the same chromosome.

Question 5

Linkage

Answer 5

keeps particular genes together while crossing over mixes
them up, producing new combinations

Question 6

We must know not only the genotype but
also

Answer 6

the arrangement of genes on the
chromosomes (Horizontal lines represent
two homologous
chromosomes)

Question 7

If genes are unlinked,
the heterozygous plant
produces

Answer 7

4 types of
gametes; two
nonrecombinant
(original combinations)
and two new
combinations

Question 8

Nonrecombinant gametes –

Answer 8

contain only original
combinations of alleles that were present in the parents

Question 9

Nonrecombinant progeny

Answer 9

display the original combinations
of traits present in the P generation

Question 10

Recombinant gametes

Answer 10

new combinations of alleles

Question 11

Recombinant progeny

Answer 11

Recombinant progeny –new combinations of traits

Question 12

Crossing over Between Linked Genes

Answer 12

Valuable for genetic variation in meisos

Crossing over is typical between genes that lie on the same
chromosome.
– Producing new combinations of traits
– Remember, takes place in Prophase I of meiosis.

Question 13

Linked Genes with Crossing Over

Answer 13

If height and leaf type are linked genes,
and NO CROSSING OVER occurs:
All four gametes produced are
nonrecombinants

If height and leaf type are linked genes,
and crossing over occurs:
Two of the four gametes produced are
recombinants

Question 14

Recombination frequency =

Answer 14

(Number of
recombinant progeny/Total number of
progeny) x 100%

Question 15

Coupling (cis configuration):

Answer 15

One chromosome contains
both wild-type alleles, one chromosome contains both
mutant alleles

Question 16

Repulsion (trans configuration): Wild-type allele and
mutant allele are found on the same chromosome

Answer 16

Wild-type allele and
mutant allele are found on the same chromosome