WorksheetsPBS
Total questions: 25
Worksheet time: 25mins
A student performed a gel electrophoresis experiment. The results are represented in the diagram
below. Compared to the fragments at the top of the gel, the fragments at the lower end are
larger, and move slower
larger, and move faster
smaller, and move faster
smaller, and move slower
Why do the fragments of DNA in gel electrophoresis travel away from the negative electrode?
DNA is negatively charged
DNA is positively charged
the agarose gel in negatively charged
the agarose gel is positively charged
In gel electrophoresis, the largest DNA fragment will appear
closest to the starting wells
farthest from the starting wells
three quarters away from the starting wells
it depends on how many fragments there are
How many fragments resulted from the cut above?
1
2
3
4
Which letter represents amplitude? (a)
A
B
C
D
E
How many restriction sites appear in the picture?
1
2
3
4
Which restriction enzyme listed below was isolated from E.coli bacteria?
AluI
HindIII
HaeII
EcoRI
This process produces millions of copies of a DNA sequence from a small amount of DNA.
Amplification
PCR (Polymerase Chain Reaction)
DNA Digestion
Transcription
The location where restriction enzymes cut DNA is called a..
nucleotide
recognition site
phosphate
molecular clevage site
Check all the places from where you can collect DNA.
Red Blood Cells
Clothing
Bone
Hair with a follicle
Body Fluids
A person's unique individual DNA code is called a ...
identity sequence
code or organization
DNA Profile
nucleotide fingerprint
This laboratory procedure is known as
CLONING
gel electrophoresis
chromatography
use of a dichotomous key
In preparation for an electrophoresis procedure, enzymes are added to DNA in order to
convert the DNA into gel
cut the DNA into fragments
change the color of the DNA
produce longer sections of DNA
Restriction Enzymes . . .
cut DNA at precise locations
help bacteria to pick up DNA
move DNA through a gel
copy DNA
Restriction Enzymes come from . . .
viruses
bacteria
goats
spiders
Why do bacteria have restriction enzymes?
To prevent being infected by viruses
To help DNA get into the cell
To be able to grow in an incubator
They don't - viruses have restriction enzymes
What charge is DNA?
positive
negative
neutral
During gel electrophoresis, DNA moves from the ___ end to the ___ end.
positive, negative
negative, positive
Which is the primary purpose of using restriction enzymes in gel electrophoresis?
It allows the strands of DNA to be cut into various lengths for testing
It restricts the number of base pairs that can be tested in a sample
It makes the testing simpler by moving the strands into the gel faster
It charges the DNA strands
Which suspect is likely guilty?
Suspect #1
Suspect #2
Suspect #3
PBS is commonly used in laboratories as a buffer solution. What does PBS stand for?
Phosphate Buffered Saline
Potassium Buffered Solution
Phosphorus Bicarbonate Solution
Polymer Buffered Saline
What is the primary purpose of using PBS in cell culture experiments?
To provide nutrients to cells
To maintain pH balance
To act as a staining agent
To increase cell growth rate
In which of the following applications is PBS NOT typically used?
DNA extraction
Protein purification
Cell washing
As a primary energy source
PBS is often used in immunoassays. What is its role in these experiments?
To enhance the signal of the assay
To wash away unbound antibodies
To act as a substrate for enzyme reactions
To directly bind to antigens
Why is PBS preferred over water for washing cells in laboratory experiments?
It is cheaper than water
It prevents osmotic shock to cells
It enhances cell adhesion
It provides essential nutrients
