Question

Can anyone tell me what the # of DNA fragments are?

Answer 1

Answer:

1. 3

2. 2

3. 3

4. 3

5. 3

6. 3

The total number of fragments is 17

Explanation:

What the image shows is 6 columns of DNA sequences. It looks like the annotations represents cut sites for restriction enzymes. Restriction enzymes cut at defined sequences. The cut site is represented by the horizontal line (see attached pic, red arrows).

That means any time there is a horizontal line, a new fragment is made. Remember that the DNA is double stranded, so the cuts made will produce what we call "overhangs" or "sticky ends" where they are uneven in length.

Column 1

There are 2 cut sites on each strand, producing 3 fragments

(TGGGC) (CTAGGGCACAT) (TCGAAC)

(ACCCGGATC) (CGTGTAAGCT) (TC)

Column 2

There is 1 cut site on each strand, producing 2 fragments

Column 3

There are 2 cut sites on each strand, producing 3 fragments

Column 4

There are 2 cut sites on each strand, producing 3 fragments

Column 5

There are 2 cut sites on each strand, producing 3 fragments

Column 6

There are 2 cut sites on each strand, producing 3 fragments