Biological Agents

Question 1

Define

Biological agent

Answer 1

Every: microorganism and human endoparasite.

Cell cultures not considered biological agents, but microorganisms present in them are.

Question 2

Define

Commensals

Answer 2

Necessary microorganisms living in and on the human body. Mutually beneficial symbiosis.

Question 3

Define

Saprophytes

Answer 3

Microorganisms living independently of humans (on the ground or on plants)

Question 4

Categories of microorganisms

Answer 4

• Bacteria
• Archaea
• Viruses
• Fungi and yeasts

Question 5

Bacteria size range

Answer 5

0.5-5 micrometers (light microscope)

Question 6

When working with bacteria that form spores…

Answer 6

Use correct disinfectants and longer autoclave times

Question 7

Bacteria dividing time (approx.)

Answer 7

30 mins

Question 8

Time for 1 bacterium to form a colony (approx.; favourable conditions)

Answer 8

16 hrs

Question 9

Are any archaea pathogenic?

Answer 9

Nope

Question 10

Virus size

Answer 10

20-300 nm (electron microscope)

Question 11

Define

Capsid

Answer 11

Protein shell of a virus

Question 12

Define

Lipoprotein envelope

Answer 12

Second layer encasing some viruses

Question 13

Steps of viral multiplication

Answer 13

1. Bind to receptors on surface of cell; penetrate cell.
2. Remove coat, replicate genetic material, produce proteins from it (host cell ribosomes).
3. New virus particles form from proteins + genetic material. Cell dies, particles released.

Question 14

Fungi and yeasts mainly cause infections in…

Answer 14

patients with immunological disorders.