Flashcards in B6 Beyond The Microscope Deck (92)
What is the average size of a bacteria cell.
A few microns or a thousandth of a mm long
What is a microbe?
A microscopic organism
What is a pathogen ?
A disease causing bacteria
What part of a bacteria helps it to move?
Flagellum it tail or whip like
What does a bacteria not have?
Nucleus. It has DNA strands inside instead
Where can bacteria survive?
Anywhere, they adapt to their environment
What are the four types of classified bacteria?
What shape is cocci bacteria?
What shape is bacilli bacteria?
What shape is vibrio bacteria?
Curved rods or v shape
What shape is spirilli bacteria?
Spiral shaped much like a spring
What does a Bactria not have (4things)
In what way do bacteria multiply?
Binary fission they do it exponentially
How is bacteria grown?
In perti dishes in agar fell. It is done in an incubator it increase the speed. the lab needs to be sterile to stop cross contamination and infections
Aseptic techniques are used.
What technique needs to be used when culturing bacteria
Why do we use aseptic techniques when handling bacteria
To protect from infection and the agar gel being contaminated by microbes
What is the aseptic technique. How do you do it?
Seal the perti dish
Dispose of bacteria safely.
How is yogurt made?
1.Milk is pasteurized to kill microorganisms
2.Starter culture is added(lactobacillus)
3.Mixture incubated in fermenter
4.Bacteria break down lactose sugar into lactic acid and the milk clots and solidifies
5. Flat ours added
What is the structure of a virus
It is not a cell. It has strands of genetic material surrounded by a protein coat. The come in many shapes and sizes.
How do viruses reproduce
Inside living cells .they attack specific host cells
How does a virus reproduce.. Stages
1.attaches to the host cell and injects genetic material
2. Uses the host cell to make new viruses inside
3. The host cell splits releasing the new viruses
How can diseases be transmitted
FOOD. Food poisoning
AIRBORNE . Influenza
CONTACT . Athletes foot
List the 4 stages in an infectious disease.
1. The microorganism entered the body
2. The reproduces rapidly
3. This is the incubation period and the organisms produce toxins which damage cells and tissues
4. The toxins cause symptoms
What does an antiseptic do
Cleans wounds and surfaces outside the body.
It prevents infection not treat it
What's an antibiotics job
A drug that's used inside the body to treat infected patients .
It only kills bacteria
How does yeast respire?
Anaerobically or are aerobically
When yeast respire anaerobically it is fermentation, what is made and used?
Glucose = ethanol + carbon dioxide
What does yeasts growth rate depend on (4)
Amount of food or yeast
Build up of waste toxins
What makes sandy soil so special
It's made up of large particles and has large air gaps
High air content and very permeable.
What is clay soils structure like?
Tiny particles with small pores.
Low air content and low permeability
What is the structure of loam soils
Mixture of sand and clay.
The structure depends on the amounts of each particles
How is cheese made?
Milk + enzymes + lactobacillus = cheese(curds and whey)
How is silage made?
Vegetation or grass + lactobacillus = silage
What is the process of making silage called?
How is vinegar made ?
Wine. Wine vinegar
Cider + acetobacter = cider vinegar
Beer Malt vinegar
What do silage cheese and yoghurt all have in common?
They all preserve food
(Milk or grass)
What is the components of soil
Humus(decomposed dead organic matter)
How is yoghurt made? 4 stages
1. Sterilise equipment
2. Pasteurise milk( 72 degrees 15secs) kill bacteria
3. Add lactobacillus form previous batch and incubate
4. add colours flavours
What is the process of making yoghurt?
What does lactobacillus do in yoghurt making?
Milk contains lactose sugar this is broken down by lactobacillus and turns into lactic acid
What happens to milks acidity as it turns into yoghurt?
Ph decreases acidity increases
How does a virus reproduce?
Inside other living cells, they use specific host cells
What's different about viruses
They have strands on genetic material inside a protein coat
How can diseases be transmitted? 4 ways
Food food poisoning
Contact athletes foot
How can poor sanitation link to disease?
Clean water supplies means low disease vice versa
Education helps stop disease eg flu education
4 stages of infectious disease..
Microorganism entered the body
It reproduces rapidly
Toxins produce symptoms
What's an antiseptic
Cleans wounds and surfaces
What does an antibiotic do?
Pills. Kills bacteria
How does bacteria become resistant to antibiotics
Not following the whole course of pills
Mutations in the cells so they don't get affected by the biotics
MRSA is one of these
What do Louis Pasteur do?
Came up with the germ theory
What did Joseph lister do?
Used the first antiseptic in surgery.
What do Alexander Fleming discover?
Antibiotic penicillin by accident
How does yeast respire
Anaerobically without oxygen
What four things does yeast growth rate depend on?
Amount of food
Toxin build up
What do worms in the soil do
Mix the soil
Reduce chances of flooding
Dead and decaying matter
Organism that feeds on detris break up the matter and help decomposes do their job
Eg, earthworm wood louse maggots
In ecosystems they break down material they are usually fungi or bacteria. They release nutrients back into the soil to be reused.
What's the best conditions for fast decay?
Warm, moist and oxygen rich
What is a saphrotroph?
The first stage of decay
They produce enzymes to break down dead matter to release nutrients
How do bacteria and fungi feed?
What is lightning a purpose in the nitrogen cycle?
To convert atmospheric nitrogen into nitrates
What does nitrifying bacteria do?
Convert ammonia into nitrates
What does denitrifying bacteria do?
Converts nitrates into nitrogen
What does nitrogen fixing bacteria do.
Lives in roots of legumes and fixes nitrogen
Define legumes And how they use nitrogen
They are self sufficient (peas clover lupine) they don't need nitrifying bacteria that other plants need. They rely on nitrogen fixing bacteria in root nodules to convert nitrogen into nitrates.
List 4 advantages of living in water
No water shortage
Less temp variation
Provides support eg jellyfish
Wast disposal easy
List 3 disadvantages of living in water
More resistant to movement
Manual water regulation required
Lots of chemicals
Define grazing food web
Photosynthetic producers common on ocean surface, lots of light
Define detritral food chains
In deeper oceans with no light it uses detrivores
Name the process in which food chains start form bacteria which get energy from chemical reactions
What is a microscopic plant in the sea?
Diatoms dinoflagellates cyanobacteria
What is microscopic animals in the sea called?
Dinoflagellates copepods krill daphnia
What does plankton rely on?
Water currents to move.
They are producers in food chains
What do seasonal variations of plankton depend on?
Light nutrients and temp
Define amoeba and their characteristics
Heterotrophs and live in fresh water whilst feeding of other organisms
They have a contractile vacuole to move nutrients
How does a contractile vacuole work (amoeba)
It gets larger and fills with excess fluid this is then discharged outside the cell. The vacuole continues this process
Name a property of fish skin
Impermeable to water so places a barrier between the body and the outside water
How do fresh water fish do osmotic regulation?
Water is gained, salts lost passively. Salts pumped in at gills. They have lots of Dilute urine
How do salt water fish use osmotic regulation?
Water lost passively at the gills
How is water polluted?
Detergents, acid rain
PCB or DDT chemical
What does non bio washing downer contain?
Chemicals that break up stains on clothesw
What does biological washing powder contain?
Chemicals and enzymes to break down stubborn stains of starch protein or fats
How do diabetic testers use enzymes?
Reagent strips change colour is glucose or sugar is present. iTunes a sequence of enzyme reactions which causes. Chemical to change colour in the strip
How is pectinase used in the food industry
Fruit juice extraction. It breaks down pectin in the cell wall causing the cells to release juice
How is rennet used in the food industry
It clots milk in the fist stages of cheese making
How is sucrase or invertase used in the food industry
Sucrose help sweeten food.
The enzyme sucrase breaks sucrose into glucose and fructose with is much sweeter. Is is used it diets and low calorie foods as it's sweeter with less sugar
Using but not taking with you
it is done with enzymes
What is an advantage if immobilising enzymes
They don't contaminate the product
When in alginate beads they are used in a continuous flow process
People who are lactose intolerant are missing a enzyme what is it?
Lactase in the digestive system
What happens in a lactose intolerant persons stomach if they drink milk?
The lactose is not broken down by lactase but fermented by the bacteria. This causes abdominal pains wind and diarrhoea