8.24.2022. part 2

Question 1

What is thought to be the origin of life on our planet?

Answer 1

Microbial origin, under the sea in hypothermal vents

Question 2

What is the difference between a microbe and a microorganism?

Answer 2

Microbe: general term to encompass 3 domains of life + acellular infectious agents
Microorganism: only refers to living things (3 domains)

Question 3

What is the difference between infection and disease?

Answer 3

Infection: colonization of host
Disease: disorder of structure or function that is not simply a direct result of physical injury

Question 4

Pathogenic microbes can be….

Answer 4

Cellular (3 domains) or acellular (A.I.A.)

Question 5

What did Agostino Bassi do?

Answer 5

first to prove that a disease was caused by a microorganism

Question 6

what was Agostino Bassi’s experiment?

Answer 6

finding that a fungus caused a disease in silkworms

Question 7

What did Robert Koch do?

Answer 7

developed scientific method that established the microbial cause of disease

Question 8

What were Koch’s postulates?

Answer 8

1. microorganism must be found in sick animals, and not healthy ones
2. must be able to isolate and grow microorganism
3. microorganism must be able to make a healthy animal sick
4. microorganism must be isolated from the newly sick animal and be identical to the one found in the originally sick animal

Question 9

What are the revised Koch’s postulates for the 21st century?

Answer 9

• nucleic acid sequence is present in most cases
• present when you’re sick, absent when you’re not
• sequence-disease association is more likely to be causal (lung tissue more affected with covid)
• should be able to show presence of microbial sequence
• sequence based forms of evidence for microbial causation should be reproducible

Question 10

What is the main challenge facing microbiology?

Answer 10

Hard to identify and grow microorganisms (we’ve only ID’d and grown 1%)

• either v harmful or v beneficial
• are mysterious diseases of microbial origin?

Question 11

What size are prokaryotes?

Answer 11

0.1-5 microns

Question 12

What size are eukaryotes

Answer 12

10-100 microns

Question 13

What size are viruses?

Answer 13

0.02-0.4 microns

Question 14

Do bacteria have DNA?

Answer 14

Yes, it’s just not enclosed in a membrane. It’s free floating. Or in a nucleoid

Question 15

Do bacteria have a membrane-bound nucleus?

Answer 15

No

Question 16

Are bacteria single celled, multi celled, or both?

Answer 16

Single celled

Question 17

What molecule is unique to bacteria?

Where is it found?

Answer 17

Peptidoglycan

Rigid cell wall

Question 18

What type of cell wall does bacteria have?

Answer 18

Rigid cell wall

Question 19

How do bacteria multiply?

Answer 19

Binary fission

Question 20

How do bacteria move?

Answer 20

Flagella

Question 21

What is a PAMP?

What’s its significance?

Answer 21

pathogen-associated molecular pattern.

body says “that’s not mine” and starts an immune response.

Question 22

How are archaea similar to bacteria?

Answer 22

Prokaryotes
Similar shapes, sizes, and appearances
Binary fission
May move via flagella
Rigid cell walls

Question 23

How are archaea different than bacteria?

Answer 23

No peptidoglycan
Ribosomal RNA sequences are different
No known pathogens

Question 24

Relate archaea to extremophiles

Answer 24

Many are extremophiles

Not all archaea are extremophiles, but most extremophiles are archaea

Question 25

Are archaea more closely related to bacteria or eukarya?

Answer 25

Eukarya