monera (eg bacteria)

Question 1

what kingdom do bacteria belong to

Answer 1

monera
they are unicellular organisms

Question 2

why are bacteria also known as prokaryotes

Answer 2

they have no membrane bound nucleus or membrane mound cell organelles

Question 3

what are the three shapes of monera

Answer 3

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

Question 4

give an example of a spherical bacteria

Answer 4

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

Question 5

give examples of rod shaped bacteria

Answer 5

tuberculosis
e. coli

Question 6

give examples of spiral bacteria

Answer 6

syphilis
cholera

Question 7

function of cell wall

Answer 7

shape and structure

Question 8

function of cytoplasm

Answer 8

contains ribosomes and storage granules but no mitochondria or chloroplasts

Question 9

function of nuclear material

Answer 9

single chromosome of DNA

Question 10

function of capsule

Answer 10

protection

Question 11

function of flagella

Answer 11

movement

Question 12

function of plasmid

Answer 12

circular piece of DNA containing few genes for drug resistance

Question 13

how do bacteria reproduce

Answer 13

asexually by binary fission

Question 14

explain the process of binary fission

Answer 14

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

Question 15

what is an autotrophic organism

Answer 15

an organism which makes their own food

Question 16

what is a heterotrophic organism

Answer 16

an organism which takes in food made by other organisms

Question 17

name the two types of autotrophic bacteria

Answer 17

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

Question 18

name the two types of heterotrophic bacteria

Answer 18

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

Question 19

name the factors affecting the growth of bacteria

Answer 19

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

Question 20

how does temperature affect bacteria

Answer 20

-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

Question 21

how does pH affect the growth of bacteria

Answer 21

enzymes will become denatured if in an unsuitable pH

Question 22

how does oxygen concentration affect the growth of bacteria

Answer 22

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

Question 23

what are the two types anaerobic bacteria

Answer 23

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

Question 24

how does external solute concentration affect bacteria growth

Answer 24

• 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

Question 25

how does pressure affect the growth of bacteria

Answer 25

-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

Question 26

beneficial bacteria

Answer 26

-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

Question 27

what are micro-organisms that cause diseases called`

Answer 27

pathogens

Question 28

harmful bacteria

Answer 28

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

Question 29

what are antibiotics

Answer 29

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

Question 30

who created the first antibiotic

Answer 30

sir alexander fleming penicillin isolated from a fungus

Question 31

what causes the growth of antibiotic resistant bacteria

Answer 31

-mutations in bacterial genes -overuse of antibiotics