B6

- a flagellum for a movement

- a cell wall to maintain shape and stop it from bursting

- DNA to control the cell's activities and replication of the cell

Spherical

Rod shaped

Spiral

Curved rods

By splitting into two in a type of asexual reproduction

Binary fission

Yes, all equipment need to be sterilised first to prevent contamination by other microbes. This is called aseptic technique

- they can survive on an enormous range of different energy sources

- can live in a very wide range of habitats

- some bacteria live by taking in organic nutrients but others can make their own food

This means that they fan very rapidly spoil food or cause disease

This means that they must be handled carefully to avoid contamination of people, animal or food

Yeast is a single celled fungus

Single celled fungus

- changing food availability

- changing temp

- changing ph

- removing waste products

The growth rate of yeast doubles for every 10°C rise in temp until the optimum is reached.

They aren't living cells but very small structures made of a protein coat surrounding a strong of genetic material

- they only reproduce in other living cells

- they only attack specific cells, which may be plant, bacterial or animal cells.

* attach itself to a specific host cell

* inject it's genetic material into the cell

* use the cell to make the components of new viruses

* cause the host cell to split open and die to release the viruses

- spread in food

- spread in water

- via direct contact

- spread in airborne droplets

By correct food hygiene

By correct water treatment

By barrier methods

By correct use of paper tissues and isolation of patients

- the microbe enters the body

- it reproduced many times without causing symptoms. This is the incubation period

- microbes cause the production of toxins

- the toxins cause symptoms such as fever

Microbes producing more of microbes without showing symptoms

* damage to sewage systems may lead to water supplies being contaminated

* damage to electrical supplies may stop refrigerators working so food decays

* large numbers of people moving to other areas means the facilities are not able to cope

* hospitals may be damaged or there may be shortage of medical staff

- Louis Pasteur who helped to prove that the germ theory of disease by realising that microbes from the air could make the food go bad

- Joseph Lister who invented the first antiseptic using carbolic acid to prevent wounds becoming infected

- Sir Alexander Fleming who discovered the first antibiotic, penicillin which is produced from a fungus

Antiseptics are used on the outside of the body to kill microbes and prevent their entry

Antibiotics tend to be used inside the body to kill microbes once they've entered

Antiseptics work on most microbes but antibiotics don't work on viruses

Some strain of bacteria are developing resistance to antibiotics.

By mutation

- all the equipment is sterilised.

- then milk is pasteurised by heating it to about 78°C

- when the milk is cooled down it is incubated with a culture of bacteria

- this is followed by sampling and then adding flavours, colours and packaging

The yeast will be killed if not ensured

Lactobacillus

It causes breakdown of lactose in milk to lactic acid which makes the yoghurt taste acidic

Glucose -> ethanol (alcohol) + carbon dioxide

- sugar is extracted by crushing grapes (wine) or from barley grain (beer )

- yeast is added

- it's kept warm to allow it to ferment. Air and other microorganisms are kept out.

- the wine or beer is allowed to clarify (clear). The clear liquid is then drawn off

- the wine or beer may then be pasteurised and put into casks or bottles

Stronger it is

C6H12O6 -> 2 C2H5OH + 2 CO2

Distillation

Oxygen in the container by respiring aerobically. This allows The number of cells to increase rapidly. Then conditions are kept anaerobic do that alcohol is made

Temp and the presence or absence of oxygen

To kill harmful microbes

Because high concentrations of alcohol kill yeast cells although some strains of yeast are more resistant to alcohol than others

Fuel that we get from plants

- alternative source to fossil fuels which are running out

- their waste makes no net increase in greenhouse gas levels

- don't release particulates when they are burnt

Areas of land are cleared of other plants in order to grow crops for biofuels

- this may mean that the fuel is not carbon neutral because the other plants cannot now remove carbon dioxide

- important habitats may be lost and species may become extinct

- mainly methane

- some carbon dioxide

- very small amounts of hydrogen, nitrogen and hydrogen sulfide

- burnt to generate electricity

- burnt to produce hot water and steam for heating systems

- used as a fuel for vehicles

Biogas production increases as temp increases up to 45°C, over it the production slows down

Biogas containing more than 50% methane can be burnt in a controlled way but a lower percentage of about 10% is explosive

Diesel and petrol

Doesn't contain as much energy as natural gas

Alcohol mixed with petrol

By fermentation

Used instead of petrol to fuel cars in countries such as Brazil

Where there is a ample sugar cane but little oil. Its cheaper than importing oil

Clay soil

* a mixture of clay and sand

* large amount of partly decomposed animal and plant waste called humus

A material that decays on top of soils layer such as leaves

- humus content can be found by burning off the humus using a Bunsen burner

Air content fan be found by seeing how much eater is needed to fill the air spaces

Water content can be found by slowly heating the soil to evaporate the water

Usually higher

Water and air

Because it will decompose to release minerals

Increase the air content of the soil

- bury organic material for decomposition by bacteria and fungi

- aerate and drain the soil

- mix up soil layers

- neutralise acid soil

Allow organisms yo respire aerobically

Because if the ph is too low some plants won't be able to grow

So that dead material is decomposed

Charles Darwin

- Theres no risk of water shortage or dehydration

- temp of water varies less than air temp

- water helps provide support

- waste products are easily disposed of into the water

- water content of the body can vary and needs to be controlled

- water is denser than air so resists movement

They have contractile vacuole

Organisms such as amoeba have a contractile vacuole that can store any excess water. The vacuole can then fuse with the cell membrane and empty the water to the outside

Phytoplankton

Zooplankton

- there will be less light in winter and deeper in winter

- the temp will be lower in winter and deeper in the water

- minerals are here up towards the end of the summer

- most rely directly on green plants

- others deeper in the ocean feed on dead material called marine snow that floats down

- some rely on bacteria deep in the ocean acting as producers

Eutrophication

Rapid growth of algae which then all die and decay. This uses up oxygen, causing the death of animals because they're unable to respire

Biological indicators for pH and oxygen

1. Toxic

2. Don't break down quickly and so accumulate and become concentrated higher up the food chain

3. Affect animals with a long lifespan such as whales

Amylase, lipase and protease

To digest carbohydrates such as starch

To digest fat and remove fatty stains

To digest protein and remove protein stains

Because this is the optimum temp got enzymes to work

The become soluble and so will easily wash out of the clothes

Because this is not the optimum for the enzymes and they might start to denature

Type of sugar

Enzymes

The product is much sweeter, allowing the food industry to use less in food products

Glucose and fructose

They are sweeter than sucrose so less has to be added to the food,lowering the cost and the energy content

@ mixing the enzyme with alginate

@ dropping the mixture into calcium chloride solution

- the mixture does not become contaminated with the enzyme

- they can be used in continuous flow processing

Because they can't produce the enzyme lactase

Bacteria in the gut ferment lactose which products diarrhoea and wind

Because bacteria have converted lactose in milk to lactic acid

- immobilised lactase is used to convert lactose in milk into glucose and galactose

- glucose and galactose can then be absorbed from the milk with no side effects

Transgenic organism

- identifying and removing a desired gene from one organism

- cutting open the dna in another organism

- inserting the new gene into the dna

- making sure that the gene works in the Transgenic organism

Enzymes

To cut open DNA during genetic engineering

Restriction enzyme

They leave several unpaired bases (single strands) on the cut end. This acts as a "sticky end"

Ligase enzymes will join DNA strands because the "sticky ends" on each cut section of DNA can join by complementary base pairing

- cutting the gene for producing human insulin out of human DNA

- cutting open a loop of bacterial DNA

- inserting the insulin gene into the loop

- inserting the loop into a bacterium

Many copies of bacteria are cultured by cloning and large quantities of insulin are harvested

Plasmids

Cytoplasm of bacteria

Vectors for genes

Via assaying technique

- scientists add genes that make the bacteria resistant to antibiotics

- the bacteria are then flooded with the antibiotics by being grown on nutrient agar containing the antibiotic

- scientists then choose the bacteria that survives

Identify

People worried that they may be used for a variety of other reasons, such as assessing the likelilhood of a person developing a disease. The info could also be used as a reason to withhold life insurances

- extracting DNA from a sample, such as blood.

- cutting up or fragmenting the DNA using restriction enzymes

- separating the fragments using electrophoresis

- making the fragments visible using a radioactive probe