Exam 2 genetics

Question 1

linked genes

Answer 1

Genes that are close together on a chromosome and likely to be inherited together

Question 1

Recombinant class

Answer 1

the gametes that result when chromosomes experience crossing over and exchange material

also the lowest number classes when looking at observed ratio

Question 2

recombinant class is lower than expected ratio

Answer 2

expect linkage of genes

Question 3

Recombination Frequency formula

Answer 3

(# of recombinant/ total offspring) * 100

< 50 means linked

Question 4

Double crossover class

Answer 4

2 lowest # of offspring

Question 5

Coefficient of Interference formula

Answer 5

(# of obs. double crossovers/ # of exp. double crossovers)

Question 6

c > 1

Answer 6

Negative Interference

more double crossovers than expected

Question 7

c < 1

Answer 7

Positive interference

less double crossovers than expected

Question 8

c=1

Answer 8

no interference

expected amount of double crossovers

Question 9

Level of Interference (I) Formula

Answer 9

I = 1-c

Question 10

Gene Conversion

Answer 10

One allele is changed to another as a result of DNA repair

results in a weird tetrad pattern such as 5:3

Question 11

Transduction

Answer 11

process by which a virus transfers genetic material from one bacterium to another

Question 12

Bacteriophages

Answer 12

Viruses that infect bacteria, use the bacteria’s resources to replicate

nucleic acid surrounded by coat material

Question 13

F’ factor

Answer 13

F plasmid genome with some of the bacterial host cell genome inside of it

Question 14

HFr

Answer 14

Host cell genome (chromosome) contains F plasmid integrated into it’s chromosomal DNA

Question 15

Conjugation

Answer 15

Process by which one bacterium transfers genetic material to another through direct contact.

Question 16

Lytic vs Lysogenic cycles

Answer 16

Lytic cycle: Bacteriophage virus infects cell, and uses the host cell material to replicate and kill the cell.

Lysogenic cycle: Bacteriophage virus infects cell and inserts itself into the host cell genome to replicate when the cell replicates.

Question 17

Endonuclease

Answer 17

Cleaves phosphodiester bond between nucleotides in DNA

Question 18

Phosphodiester bonds

Answer 18

Linkage between adjacent bases in a DNA strand

Question 19

solenoid

Answer 19

nucleosomes form a helix when stacked up, making a solenoid fiber, a unit of DNA compaction.

Question 20

Loops

Answer 20

Solenoid fiber arranged into loops of varying size that are anchored to protein scaffold

Question 21

Rosettes

Answer 21

loops arrange into these helical shapes that include about 6 loops, which then organize into a coil

Question 22

Okozaki fragments

Answer 22

short sequences of DNA nucleotides which are synthesized discontinuously and later linked together by the enzyme DNA ligase to create the lagging strand during DNA replication

Question 23

blackburn used the ciliate protists Tetrahymena and Oxchytricha to find
telomeres. Give a brief explanation of what makes these organisms so useful for
telomere studies?

Answer 23

Large Telomeres, both have telomorase activity, rapid growth of these organisms