DNA mutation structures

Practice Question Solving
1

In which of the following structure(s) can DNA mutations occur?

  1. retrovirus
  2. chloroplasts
  3. erythrocytes

A. 1 only

B. 2 only

C. 3 only

D. 1 and 2 only

E. 2 and 3 only

The key says E. Can’t retroviruses occur DNA mutations?

1 Like
2

Hey,

I would actually say B should be the correct answer.

Retroviruses have RNA strands only, so DNA mutations cannot occur.

Chloroplasts have circular DNA, so mutations can occur.

Mature erythrocytes do not have nucleus nor mitochondria, so there is no DNA and therefore DNA mutations should not occur there either.

3 Likes
3

but in the example of erythrocytes as red blood cells, wouldn’t a change in the gene for haemoglobin in the blood cell affect the structure of the red blood cell or maybe that doesn’t count as a DNA mutation?

4

hmm I think the mutation would occur in the zygote or embryo before the formation of multipotent adult stem cells in bone marrow. Thus upon their cell differentiation they would produce a faulty haemoglobin

1 Like
5

hmmm yes yes that’s true since its a genetic disorder. thanks darius:))

2 Likes
6

no worries, this is a very tricky question i must say:D

2 Likes