Topic 10: Prokaryotes Flashcards
What are prokaryotes characterized by?
Small mircoscopic size and unicellularity
What distinguishes prokaryotes from eukaryotes
Lack of
- membrane bound organelles
- circular genones
- lack of a nucleus
Do almost all prokaryotes have a cell wall?
Yes
What is peptidoglycan
A network of sugar polymers in bacterial cell wall that are cross-linked by short peptides that
What are the Structural functions that crontibuted to prokaryotic success
-cell srface structure
-endospores
- motility
- simple internal organization and DNA
- reproduction by binary fission
What is gram staining
A method to distinguish gram positive and gram negative bacteria
What do gram positive bacteria have in their cell wall
A thick layer of peptidoglycan that trap cyrstal violet crystals
What is the cell wall structure of gram negative bacteria
A thinlayer of peptidoglycan in between two lipid bilayrs
Which bacteria (negative/positive) are harder to treat since they are resistant to antibiotics
Gram negative
What is the function of a capsule in prokaryotes
Allows for adhesion to join cells and surfaces
Prokaryotes have a sticky poly saccharide protein layer called a ____
Capsule
What is the role of a capsule
Retain water, and protect cells from dessication, allow for invasion of the immune system in a host
What is an endospore
A dormant cell that develops in some prokaryotes when environment conditions become unfavourable and dissapear when favourable conditions are met
Has a coat that confers resistance
Prokaryotes have the ability to move ___
Actively
What movement do prokaryotes typically achieve?
Flagella (whip like movement)
