Prokaryotic cells and viruses Flashcards
What are prokaryotes?
Single-celled organisms
What is an example of a prokaryotic?
Bacteria
What is their cell-surface membrane made from?
Proteins and lipids
What is the function of a cell surface membrane?
to control the movement of substances in and out of the cell
What does the cell wall do?
Supports the cell
Prevents it from changing shape
What are the parts of a prokaryotic cell?
Cytoplasm Cell wall Cell membrane Capsule Ribosomes Plasmid DNA Flagellum
What is the flagellum?
long, tail-like structure
What is the function of the flagellum?
Rotate for movement of the cell
Where is the DNA found? Why?
Free in the cytoplasm
No nucleus
What is the capsule?
Protective slime layer
What are plasmids?
Small loops of DNA
What genes do plasmids contain?
Antibiotic resistance
What length are prokaryotic cells?
less than 2µm
What is the process called by which prokaryotic cells replicate?
Binary fission
What is step one in binary fission?
The circular DNA and plasmid replicate
In step one of binary fission, how many times is the DNA loop replicated?
Once
In step one of binary fission, how many times can the plasmid be replicated?
Lots of times
What is step two of binary fission?
The cell gets bigger
The DNA loops move to opposite sides of the cell
What is step 3 of binary fission?
The cytoplasm divides
New cell walls form
What is the fourth step of binary fission?
Two daughter cells are produced
In binary fission, what do each of the daughter cells have?
One copy of the circular DNA
What are viruses?
acellular
What are viruses consisted of?
Nucleic acids surrounded by protein
Are viruses dead or alive?
Dead
