Unit 1 Topic 2 - Organisation Of DNA

Question 1

Describe the differences between prokaryotes and eukaryotes

Answer 1

Prokaryotes:
Prokaryotes do NOT have a nucleus.
These are bacteria and Archaea

Eukaryotes:
DNA of a Eukaryotic cell is generally animal, plant & yeast

Question 2

Describe how DNA is organised in prokaryotes

Answer 2

Prokaryotes DNA is found in the cytoplasm as:
1. Circular chromosomes
2. Plasmids

Question 3

Describe how DNA is organised in eukaryotes (nucleus, mitochondria & chloroplasts)

Answer 3

Eukaryotic cell DNA is found in:
1. Nucleus (linear chromosomes)
2. Mitochondrial DNA (Circular Chromosomes)
3. Chloroplast DNA in plant cells (Circular Chromosomes)
4. Plasmids (ONLY IN YEAST)

Question 4

Explain how linear chromosomes are organised to prevent them becoming tangled.

Answer 4

DNA in the NUCLEUS is organised to avoid the strands from becoming tangled. It is:
•TIGHTLY Coiled
•Packaged/wrapped around bundles of proteins called histones.