Gel Electrophoresis and DNA Fingerprint

What is the role of restriction enzymes?

• To cut the DNA into fragments

• To dye the DNA

• To move the DNA fragments throughout the gel

• To remove DNA from the nucleus

According to the gel electrophoresis results shown, which suspect committed the crime?

• A

• B

• C

• D

Tags

NGSS.HS-LS3-1

According to the gel electrophoresis results shown, which suspect committed the crime?

• Suspect 1

• Suspect 2

• Suspect 3

• not enough data to tell

The table shows the STR alleles of a set of parents for a specific gene. Based on the STRs of the mother and father, which of the following is NOT a possible STR combination for the offspring?

• 27, 8

• 32, 19

• 27, 32

• 8, 32

Tags

NGSS.HS-LS3-1

NGSS.HS-LS3-2

The table shows the STR alleles of a set of parents for a specific gene. Based on the STRs of the mother and father, which of the following is NOT a possible STR combination for the offspring?

• 11, 13

• 13, 13

• 12, 11

• all are possible combinations

Tags

NGSS.HS-LS3-1

NGSS.HS-LS3-2

This laboratory procedure is known as

• CLONING

• gel electrophoresis

• chromatography

• use of a dichotomous key

Answer explanation

The laboratory procedure known as gel electrophoresis is used to separate and analyze DNA fragments based on their size and charge.

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

Answer explanation

Enzymes are added to DNA to cut it into fragments for electrophoresis, not to convert it into gel, change its color, or produce longer sections of DNA.

Why do the fragments of DNA in gel electrophoresis travel away from the negative electrode?

• DNA is negatively charged so attracted to the positive end of the unit

• DNA is positively charged to attracted to the negative end of the unit

• the agarose gel in negatively charged

• the agarose gel is positively charged

Answer explanation

DNA fragments in gel electrophoresis travel away from the negative electrode because DNA is negatively charged and is attracted to the positive end of the unit.

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

Answer explanation

The largest DNA fragment will appear closest to the starting wells in gel electrophoresis.

What is the approximate size of the largest fragment for elephant #1 (on left)?

• 200 base pairs

• 180 base pairs

• 190 base pairs

• 70 base pairs

Answer explanation

The approximate size of the largest fragment for elephant #1 (on left) is 180 base pairs, which is the correct choice.