Lecture 12

Question 1

chromosomal duplications are

Answer 1

repeated segment of chromosome

Question 2

how do duplications arise

Answer 2

through replication error prior to meiosis

through unequal crossing over between synapsed chromosomes during meiosis

Question 3

what are three results from duplications?

Answer 3

gene redundancy
phenotypic variation
source of genetic variability during evolution

Question 4

redundancy is

Answer 4

ribosomal RNA

Question 5

redundancy

Answer 5

multiple copies of genes code for rRNA

Question 6

is a single copy sufficient in redundancy?

Answer 6

no

Question 7

DNA that codes for rRNA is called

Answer 7

rDNA

Question 8

what is essential in abundance in a cell to support protein synthesis

Answer 8

gene product

Question 9

how do new genes arise?

Answer 9

non-functionalization
neo-functionalization
sub-functionalization

Question 10

inversions are

Answer 10

rearrangement of linear gene sequence

Question 11

during inversions the segment of a chromosome turns how far within a chromosome

Answer 11

180 degrees

Question 12

is there a loss of genetic information in inversions

Answer 12

no

Question 13

how many breaks do inversions require

Answer 13

2

Question 14

when does the chromosomal loop form

Answer 14

prior to breakage

Question 15

what do inversions create to close together and rejoin

Answer 15

sticky ends

Question 16

what may the inverted segment not include

Answer 16

centromere

Question 17

paracentric inverision

Answer 17

does not include centromere

Question 18

pericentric inversion

Answer 18

includes the centromere

Question 19

when does linear (normal) synapse not occur

Answer 19

it is not possible if only one member of homologous pair has inverted segment

Question 20

inversion heterozygotes are

Answer 20

organisms with one inverted chromosome and one non-inverted homolog

Question 21

pairing between inversion heterozygotes require an

Answer 21

inversion loop

Question 22

how many recombinants does a crossover of paracentric inversions produce

Answer 22

two- dicentric and acentric

Question 23

dicentric chromatid

Answer 23

two centromeres

Question 24

acentric chromatid

Answer 24

lacking a centromere

Question 25

translocation is the…

Answer 25

movement of chromosomal segment to new location in genome

Question 26

reciprocal translocation is

Answer 26

exchange of segments between non-homologous chromosomes

genetic information not lost or gained just rearranged

does not directly alter viability of individual

Question 27

homologs that are heterozygous for reciprocal translocation undergo…

Answer 27

unorthodox synapsis during meiosis

Question 28

what are two possible segregation patterns

Answer 28

alternate segregation leads to normal and balanced gametes

adjacent segregation leads to gametes containing duplications and deficiencies.

Question 29

alternate segregation leads to

Answer 29

normal and balanced gametes

Question 30

adjacent segregation leads to

Answer 30

gametes containing duplications and deficiencies