Monera (Bacteria)

Question 1

micro organism definition

Answer 1

a small living thing

Question 2

bacteria are…

Answer 2

unicellular
microscopic
prokaryotic
heterotroph and autotroph

Question 3

prokaryotic definition

Answer 3

do not have a nucleus or cell enclosed organelles

Question 4

shape of bacteria

Answer 4

round
rod
spiral

Question 5

examples of bacteria

Answer 5

pneumonia
ecology
syphillus
tuberculosis
cholera

Question 6

capsule function

Answer 6

further protection

Question 7

plasmid function

Answer 7

resistance to drugs/antibiotics and used in genetic engineering

Question 8

flagella function

Answer 8

movement

motile

Question 9

are bacteria motile?

Answer 9

yes — flagella

Question 10

How do bacteria reproduce?

Answer 10

Asexually, by Binary Fission

Question 11

Binary Fission steps

Answer 11

1. cell reaches a certain size & DNA strand replicates itself
2. Now 2 identical strands of DNA
3. Cell ELONGATES with a strand of DNA attached to each side
4. Cell splits into 2 similar sized cells

Question 12

Mutations in Bacteria

Answer 12

Offspring genetically identical.
Short life span of bacteria mean that any new variation produced by a mutation can be passed quickly to a large number of bacteria.
This is how bacteria evolve and become resistant to new antibiotics.

Question 13

Nutrition in Bacteria
Heterotrophic : Saprophytic

Answer 13

Eg: Bacteria of decay

Question 14

Nutrition in Bacteria
Heterotrophic : Parasitic

Answer 14

Eg: Bacillus anthracis

Question 15

Nutrition in Bacteria
Autotrophic : Photosynthetic

Answer 15

Eg: purple sulphur bacteria

Question 16

Nutrition in Bacteria
Autotrophic : Chemosynthetic

Answer 16

Eg: Nitrifying bacteria

Question 17

Photosynthetic bacteria definition

Answer 17

Use light energy to make food
eg: purple sulphur bacteria

Question 18

Chemosynthetic bacteria definition

Answer 18

Use energy from chemical reactions to make food
eg: nitrifying bacteria

Question 19

Saprophytic bacteria definition

Answer 19

live off dead plants / animals (carbon cycle)
eg: bacteria of decay

Question 20

Parasitic bacteria definition

Answer 20

take food from live host, some cause disease
eg: bacillus anthracis (causes anthrax)

Question 21

Factors affecting growth of bacteria
(limiting factors)

Answer 21

Temp
pH
Oxygen Conc
External solute Conc
Pressure

Question 22

1. Temperature

Answer 22

most bacteria grow well between 20/30°C
some can tolerate higher temps without enzymes being denatured
low temps slow down rate of reaction of enzymes resulting in SLOWER GROWTH

Question 23

2. pH

Answer 23

If bacteria is placed in an unsuitable pH it’s enzymes will become denatured.
Most bacteria grow at pH7
Some can tolerate very low/high pH values.

Question 24

3. Oxygen Concentration

Answer 24

Aerobic bacteria need oxygen for respiration (eg: streptococcus) (this is why oxygen is sometimes bubbled through bioreactors)
Anaerobic bacteria don’t require oxygen to respire.
- Faculative anaerobes can respire with or without (eg: ecoli)
- Obligate anaerobes can only respire in the absence of oxygen (eg: clostridium tetani)

Question 25

Aerobic bacteria

Answer 25

need oxygen to respire

Question 26

Anaerobic Bacteria

Answer 26

don’t need oxygen to respire

Question 27

Faculative anaerobes

Answer 27

can respire with or without oxygen

Question 28

Obligate anaerobes

Answer 28

can only respire without

Question 29

4. External solute concentration

Answer 29

Bacteria can gain or lose water by osmosis If external solute conc is Higher than the bacterial cytoplasm - water will move out of bacteria, causing dehydration (tinned fish, fruits) Lower than the bacterial cytoplasm, water will enter bacteria (cell wall prevents bursting)

Question 30

5. Pressure

Answer 30

growth of bacteria is inhibited by high pressures some can withstand high pressures Pressure tolerant bacteria for use in bioreactors can be formed by genetic engineering techniques (GMO)

Question 31

Economic importance of bacteria Beneficial

Answer 31

lactobacillus bulgaricus converts milk to yogurt and cheese antibiotics can be formed bacteria are active in carbon and nitrogen cycles

Question 32

Economic importance of bacteria Harmful

Answer 32

pathogenic bacteria can cause disease in humans and animals (pathogens) bacteria can cause food spoilage bacteria can cause tooth decay

Question 33

pathogen definition

Answer 33

organisms that cause disease

Question 34

Lag phase

Answer 34

Bacterial cells adapting to new conditions. They’re producing enzymes to digest the nutrients Rate of growth begins to increase at end of lag

Question 35

Log phase

Answer 35

Rapid period of growth due to: bacteria developing enzymes and there are plenty of nutrients lack of waste products being produced

Question 36

Stationary phase

Answer 36

Rate of growth levels off Death rate equals birth rate lack of food, space, moisture and oxygen

Question 37

Death phase

Answer 37

Durina this phase more bacteria are dying than are being produced. This is because : - few nutrients are left - bacteria are poisoned by the waste produced in such large numbers - This the rate of grouth is falling

Question 38

favourable conditions for bacteria growth

Answer 38

O2 Food Space Moisture PH Temp

Question 39

Endospore formation

Answer 39

Occurs during binary fission 1. DNA replicates itself 2. One of the new strands of Dna becomes enclosed in a tough walled capsule called an endospore, formed inside the parent cell. 3. Parent cell breaks down 4. Endospores can remain dormant for long time 5. When conditions are favourable new bacteria can be formed again and continue to reproduce

Question 40

Bioreactors definition

Answer 40

a large, stainless steal vessel which biological reactions take place in the presence of micro organisms.

Question 41

Batch food processing

Answer 41

1. A fixed amount of nutrient is added to bioreactor at start 2. Micro organisms go through lag and log and stationary phase where most product is formed 3. Product is formed over short period of time. 4. Process starts again

Question 42

Continuous flow processing

Answer 42

1. Nutrients added all the time 2. Micro organisms mainly go through log phase where most product is formed 3. Long period of time

Question 43

Antibiotics

Answer 43

antibiotics are chemicals produced by micro organisms that stop growth or kill other micro organisms without damaging human tissue (NOT VIRUSES)

Question 44

Antibiotic resistance

Answer 44

Occurs during binary fission 2. mutations in bacteria genes cause antibicic resistance 3. This is known as natural selection 4. These changes in the genes can be passed on quickly to new bacteria » surviving chains multiply 5. This leads to build up of an antibiotic resistant population.

Question 45

how does antibiotic resistance occur

Answer 45

misuse of antibiotics