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Flashcards in Distribution & Enzymes Deck (29):

What is a habitat?

the place where an organism lives


What does 'the distribution of organisms' mean?

where an organism is found


What factors affect the distribution of organisms?

water availability
oxygen/ carbon dioxide supply
nutrient supply
amount of light


What is a quadrat?

a square frame enclosing a known area, usually 1m2


How can you examine the distribution of organisms using a quadrat?

1/ Split the first sample area into a grid
2/ pick a random coordinate and place the quadrat there
3/count all the organisms within the quadrat
4/repeat at different points in the same sample area
5/ calculate mean
6/ do the same for sample area 2


how do you work out a population size?

number of organisms per m2 * total area of habitat


What is a transect?

Lines that can help find out how an organism is distributed across an area


give an example of what you could find out from using a transect

if an organism becomes more/less common as you move from a hedge towards the middle of a field.


How do you use a transect?

count all the organisms that touch the line or place quadrats along the line.


How could you make your results more reliable?

By using a larger sample size e.g using more quadrats and transects


what are enzymes?

protein consisting of big molecules


what do enzymes work as?

biological catalysts, structural components of tissues, hormones and antibodies.


as catalysts, what do enzymes do and not do?

Enzymes do not make reactions happen which would not normally, they just speed up reactions without being changed or used up.


What do digestive enzymes do?

They break down big molecules like starch, proteins and fats into smaller molecules like sugar, amino acids, gylcerol and fatty acids.


Why do digestive enzymes have to do this?

because they become smaller molecules so can pass through digestive system walls easily.


What do carbohydrase enzymes do and give an example of one

They break down starch to glucose and fructose
e.g amylase


What do protease enzymes do and give an example of one

They break down big proteins into amino acids
e.g pepsin


What do lipase enzymes do and give an example of one

break down fats and oils (aka lipids) into glycerol and fatty acids
e.g pancreatic lipase


Where is amylase made?

salivary gland
small intestine


Where is protease made?

small intestine


Where is lipase made?

small intestine


What is the process of digestion?

1/ Mechanical digestion in the mouth
2/ salivary gland produces amylase enzymes in the saliva which start to break down the food
3/ Bolys formed
4/ Bolys enters stomach
5/ Stomach produces protease enzymes called pepsin and releases hydrochloric acid to kill bacteria and give the right pH for the protease to work.
6/ Bile from the gall bladder in the liver is released into the small intestine which neutralises the stomach acid and emulsifies fat.
7/ Pancreas also releases protease, amylase and lipase enzymes into small intestines, the pancreatic juice breaks down the fat.
8/ The first 1/5 of the small intestine finishes off digestion
9/ the rest of the intestine absorbs the products.


How are enzymes used commercially to make chocolate sweets?

-The centre of the chocolate begins rock hard
-melted chocolate is poured arround it
-Chocolates are frozen
-they are then left in a warm environment and the carbohydrase enzyme digests the inside
hence the centre goes soft


Why is baby food so runny and pulpy?

The baby food has been liquidized by enzymes- pre- digested


What happens if an enzyme gets too hot?

some of the bonds holding the enzyme together break. This destroys the enzymes special shape and so it won't work anymore. We say that the enzyme has denatured.


At what temperature do enzymes in the human body work best?

37 degrees celcius


What enzymes are used in biological detergents?

mainly protein- digesting enzymes (proteases) and fat digesting enzymes (lipases). The enzymes break down animal and plant matter so they're ideal for removing stains like food or blood. More effective at lower temperatures.


What are the advantages of using enzymes in industry?

- They're specific, so they only catalyse the reaction you want them to.
- using lower temperatures and pressures means a lower cost as it saves energy.
- enzymes work for a long time, so after the initial cost of buying them you can continually use them.
- they are biodegradable and therefore cause less environmental pollution.


What are the disadvantages of using enzymes in industry?

-Some people can develop allergies to the enzymes
- Enzymes can be denatured by even a small increase in temperature and are vulnerable to poisons and change in pH. Their conditions must be tightly controlled.
- Enzymes can be expensive to produce
- contamination of the enzyme with other substances can affect the reaction.