monera (eg bacteria) Flashcards

You may prefer our related Brainscape-certified flashcards:
1
Q

what kingdom do bacteria belong to

A

monera
they are unicellular organisms

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

why are bacteria also known as prokaryotes

A

they have no membrane bound nucleus or membrane mound cell organelles

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

what are the three shapes of monera

A

spherical (cocci)
rod (bacillus)
spiral (spirillum)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

give an example of a spherical bacteria

A

staphlococcus aureus (causes pneumonia)
streptococcus (causes sore throat)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

give examples of rod shaped bacteria

A

tuberculosis
e. coli

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

give examples of spiral bacteria

A

syphilis
cholera

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

function of cell wall

A

shape and structure

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

function of cytoplasm

A

contains ribosomes and storage granules but no mitochondria or chloroplasts

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

function of nuclear material

A

single chromosome of DNA

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

function of capsule

A

protection

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

function of flagella

A

movement

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

function of plasmid

A

circular piece of DNA containing few genes for drug resistance

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

how do bacteria reproduce

A

asexually by binary fission

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

explain the process of binary fission

A
  1. the chromosome attaches to the cell membrane and the DNA is replicated
    2.the cell elongates and the two chromosomes separate
    3.the cell wall grows to divide the cell in two
    4.two identical daughter cells are formed
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

what is an autotrophic organism

A

an organism which makes their own food

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

what is a heterotrophic organism

A

an organism which takes in food made by other organisms

17
Q

name the two types of autotrophic bacteria

A

photosynthetic bacteria
-use light energy to make food eg purple sulphur bacteria
chemosynthetic bacteria
-use energy from chemical reactions to make food
eg nitrifying bacteria

18
Q

name the two types of heterotrophic bacteria

A

saprophytic bacteria
-live off dead organic matter
eg bacteria of decay in soil
parasitic bacteria
-take food from live host, some cause diseases
eg bacillus anthracis- causes anthrax

19
Q

name the factors affecting the growth of bacteria

A

-temperature
-oxygen concentration
-pH
-external solute concentration
-pressure

20
Q

how does temperature affect bacteria

A

-most bacteria grow well between 20-30 degrees
-some can tolerate higher temperatures without their enzymes becoming denatured
-low temperatures slow down the rate of reaction of enzymes resulting in slower growth

21
Q

how does pH affect the growth of bacteria

A

enzymes will become denatured if in an unsuitable pH

22
Q

how does oxygen concentration affect the growth of bacteria

A

-aerobic bacteria require oxygen for respiration eg streptococcus
-this is why oxygen is sometimes bubbled through bioreactors

23
Q

what are the two types anaerobic bacteria

A

-facultative anaerobes
can respire with or without oxygen eg e.coli
-obligate anaerobes
can only respire without oxygen eg clostridium tetani (causes tetanus)

24
Q

how does external solute concentration affect bacteria growth

A
  • bacteria can gain or lose water y osmosis
    -if the external solute concentration is higher than the bacterial cytoplasm, water will move out of bacteria (dehydration)
    -food preservation techniques are based on this
    -if the external solute concentration is lower than the bacterial cytoplasm, solute concentration water will enter the bacteria
    -cell wall prevents bursting in most cases
25
Q

how does pressure affect the growth of bacteria

A

-the growth of most bacteria is inhibited by high pressures
-some bacteria can withstand high pressures
-pressure tolerant bacteria for use in bioreactors can be formed by genetic engineering techniques

26
Q

beneficial bacteria

A

-lactobacillus is used to convert milk products such as cheese and yoghurt
-genetically modified bacteria such as e.coli are used to make products such as insulin, enzymes, drugs, food flavourings and vitamins

27
Q

what are micro-organisms that cause diseases called`

A

pathogens

28
Q

harmful bacteria

A

-bacillus anthracis causes anthrax in humans
-tuberculosis, typhoid, cholera etc

29
Q

what are antibiotics

A

substances produced by micro-organisms that stop the growth of or kill other micro-organisms without damaging human tissue
can be used to control bacterial and fungal infections but do not effect viruses

30
Q

who created the first antibiotic

A

sir alexander fleming
penicillin isolated from a fungus

31
Q

what causes the growth of antibiotic resistant bacteria

A

-mutations in bacterial genes
-overuse of antibiotics