Lab 3: DNA isolation

Question 1

Nucelotides are _____ attached to each other and ___ bonded to a second DNA strand

Answer 1

covalently
hydrogen

Question 2

In this lab, ____ will be used to break open the cell membrane but keep the nuclear membrane intact

Answer 2

TRITON X 100 detergent

Question 3

A homegenate contains:

Answer 3

cytoplasmic components, organelles, and plasma membrane fragments

Question 4

The nuclei in a homogenate can be separated from other components by

Answer 4

low-speed centrifugation

Question 5

EDTA is added to the pellet to inhibit _____activity, an enzyme that will hydrolyze the DNA once normal cell regulatory mechanisms have been disrupted

Answer 5

DNAse

Question 6

EDTA is a ____ agent that binds divalent cations, which are necessary for a hydrolyzing ion’s activity

Answer 6

Chelating

Question 7

In order to break down the nuclear envelope as well as denature proteins, a second detergent is used,_____

Answer 7

Sodium Dodecyl Sulfate

Question 8

SDS inhibits…

Answer 8

most protein-protein and protein-lipid interactions, such as those in nuclear envelope by denaturing histones and disrupting bonds linked to DNA

Question 9

DNA wrapped around ___ form the basic packing unit of DNA, called the nucleosome

Answer 9

histones

Question 10

In this lab, sodium chloride is used to…

Answer 10

precipitate the nnuclear proteins that are separated from the DNA during centrifugation

Question 11

DNA is insoluble in alcohol, so it will ___when ethanol is added

Answer 11

precipitate

Question 12

in this lab, you will centrifuge the wheat germ for five minutes at

Answer 12

2.0 X 1000 rpm