LECTURE 2B: THE MICROBIAL WORLD

Question 1

Microorganisms can be both _____and
____ to humans

Answer 1

Beneficial; harmful

Question 2

Give five (5) impact of microorganisms on human society

Answer 2

1. agents of disease
2. food and agriculture
3. valuable products for human benefit
4. energy generation
5. environmental clean-up

Question 3

essential for food chain, food security and climate mitigation

Answer 3

microbial communities

Question 4

Small numbers of potentially ____ microbes are a natural part of these communities

Answer 4

harmful

Question 5

Aquatic animals: ___ have microbial communities that support their health.

Answer 5

Fish

Question 6

Water bodies: Microbes in ____ phytoplankton communities are food for fish

Answer 6

Water bodies

Question 7

Shellfish and disease: Some microbial compounds accumulate in shellfish and cause ___ ____

Answer 7

food poisoning

Question 8

They are a food source for us

Answer 8

Single celled algae

Question 9

Agriculture: Some bacteria help ____ growth and ___ plants against diseases.

Answer 9

Crop; defend

Question 10

Plants and disease: Some microbes can cause _____ and _____, in the right environment

Answer 10

plant disease and food losses

Question 11

Animals: Have microbial communities that are ___ of the animal’s health

Answer 11

supportive

Question 12

Microbes in foods: Wrong ____ causes food to go rotten as molds take over the microbial community. These microbes often cause _____

Answer 12

food storage; food poisoning

Question 13

Food waste: rotting of food means microbes ____so that nutrients can be released back into the environment

Answer 13

Recycle food leftovers

Question 14

common when immune systems are weak

Answer 14

Microbial infections

Question 15

influenced by the food we eatt

Answer 15

gut bacteria

Question 16

Foods like yoghurt and seurkraut are rich in _____ bacteria that outnumbered those microbes which cause food go rotten.

Answer 16

Beneficial bacteria

Question 17

They are often part of the natural host microbial community and attack when immunity is weak.

Answer 17

potentially harmful microbes

Question 18

The animal food chain may spread ____

Answer 18

anti-microbial resistances.

Question 19

___form spider webs in soil to connect plants, ____ are near plant roots

Answer 19

Fungi; bacteria

Question 20

reveal three deeply branching domains of life

Answer 20

Archaea, Bacteria, Eukarya

Question 21

Types of metabolism:

Answer 21

Photoautotroph
Photoheterotroph
Organoheterotroph
Lithoautotroph
Lithoheterotroph
Fermentation
Anaerobic respiration

Question 22

Carbon and energy source of different types of metabolism:
1. Photoautotroph
2. Photoheterotroph
3. Organoheterotroph
4. Lithoautotroph
5. Lithoheterotroph
6. Fermentation
7 Anaerobic respiration

Answer 22

1. CO2 ; light
2. organic; light
3. organic; organic
4. CO2; inorganic
5. Organic; inorganic
6. organic ; organic
7. either; either

Question 23

Bacteria house

Answer 23

Eukaryotes

Question 24

Physological capabilities of microbes

Answer 24

• High acid
  High pressure
  High temperature
  Freezing temperature
  Alkaline environments
  High salt
  High radiant resistance

Question 25

_________contributes substantially to CO2 sequestration.

Answer 25

Microbial primary production

Question 26

Marine microorganisms ____ nutrients for use in the marine food web and in the
process _____ to the atmosphere

Answer 26

recycle ; release CO2