prokaryotic cells Flashcards
1
Q
what is a prokaryotic cell?
A
a cell with no nucleus or membrane bound organelles
2
Q
what is the approximate size of a bacterial prokaryotic cell
A
0.1 - 10 micrometres
3
Q
describe the DNA in a prokaryotic cell
A
- usually one DNA molecule
- chromosomal = compact
- free in cytoplasm
- contains genes needed to grow and reproduce
- plasmid DNA contains additional genes
4
Q
describe the ribosomes in prokaryotic cells
A
smaller than in eukaryotic cells (70S)
5
Q
describe the cell wall in prokaryotic cells
A
- made of peptidoglycan
- composed of carbohydrates and amino acids to stop it bursting
6
Q
describe the flagella in prokaryotic cells
A
- thinner than eukaryotes
- energy from chemiosmosis
- no 9+2 arrangement
- rotates to enable movement
- attached to cell membrane and rotated by molecular motor
7
Q
what is the function of pili?
A
increases surface area
8
Q
what is the prokaryotic capsule?
A
- waxy layer surrounding cell wall
- prevents it drying out
- protects against white blood cells
9
Q
describe 2 differences between mitochondria and prokaryotic cells
A
- prokaryotic cells have a cell wall
- mitochondria has a double membrane
