Organisation of DNA in prokaryotes and eukaryotes Flashcards
What type of chromosomes do eukaryotes have?
Linear
What are linear chromosomes?
Strings of DNA wrapped around proteins
Where are linear chromosomes contained?
Nucleus
Which eukaryotic organelles contain small circles of DNA?
Chloroplasts and mitochondria
Do prokaryotes have a nucleus?
No
Do eukaryotes have a nucleus?
Yes
What type of chromosomal DNA do prokaryotes have?
Circular
What type of chromosomal DNA do eukaryotes have?
Linear
Give an example of a prokaryote
Bacteria
Characteristics of a prokaryote
Have no nucleus but contain a circular chromosome and can also contain smaller circles of DNA called plasmids.
Do prokaryotes have plasmids?
Yes
Do eukaryotes have plasmids?
No, excluding yeasts
Do prokaryotes have organelles with circular DNA?
No
Do eukaryotes have organelles with circular DNA?
Yes (chloroplasts and mitochondrion)
Ribosome size of prokaryotes
Small
Ribosome size of eukaryotes
Large
Cell size of prokaryotes
Small
Cell size of eukaryotes
Large
How is DNA packed in linear chromosomes?
DNA is tightly coiled around histone proteins and then the coiled DNA is folded and folded again.
Why is DNA a unique molecule?
Because is can reproduce itself exactly
When does replication of DNA take place?
Before mitosis
What does replication of DNA ensure?
That the daughter cells have a full chromosome complement