Bacteria Flashcards
1
Q
what are the 3 classifications of bacterial cells
A
- Gut microbiota → Beneficial gut bacteria which aid in digestion, vitamin production and protection against pathogens
- Probiotics → live microorganisms which may give health benefits when consumed in adequate amounts
- Pathogenic Bacteria → Bacteria that cause disease by invading, releasing toxins and triggering immune responses
2
Q
what are the different types of bacterial shapes (10)
A
Cocci - ball
Bacilli - pill shapes
Club rod - dumbbell-shaped
Vibro - banana-shaped
Spirillum
Helical form
Spirochete
Filamentous
Hypha
Stalk
3
Q
How are bacteria identified through staining (4)
A
Gram ve- = pink & thin walled
Gram ve+ = purple & thick walled
4
Q
What are the structures and functions of a bacterial cell that enables infection?
A
- Capsule - protects the bacteria from desiccation by helping cells adhere to surfaces. And providing resistance to phagocytosis.
- Fimbriae - which assists with adherence to host and colonisation (infection).
- Pili - assist in surface attachment and facilitate conjugation (genetic exchange).
5
Q
What is the structure and function of a bacterial cell that enables motility. (2)
A
- The flagellum assists in swimming and bacterial mobility
- they are helical in shape and exist in 3 different arrangements: PERITRICHOUS, POLAR, LOPHOTRICHOUS
6
Q
What is the structure and function of a bacterial cell that enables bacteria survival. (6)
A
When bacteria are starved or put under extreme stress they can go under sporulation and enter a ‘dormant’ state to survive.
- vegetative growth stops and DNA is duplicated.
- septum forms and divides the cell unsymmetrically.
- larger compartment engulfs smaller compartment.
- forespore is formed in the mother cell (smaller compartment).
- peptidoglycan material is layed down between the two membranes surrounding the forespore.
- the cell is degraded and the endospore is released.
