Distribution & Enzymes

Question 1

What is a habitat?

Answer 1

the place where an organism lives

Question 2

What does ‘the distribution of organisms’ mean?

Answer 2

where an organism is found

Question 3

What factors affect the distribution of organisms?

Answer 3

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

Question 4

What is a quadrat?

Answer 4

a square frame enclosing a known area, usually 1m2

Question 5

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

Answer 5

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

Question 6

how do you work out a population size?

Answer 6

number of organisms per m2 * total area of habitat

Question 7

What is a transect?

Answer 7

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

Question 8

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

Answer 8

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

Question 9

How do you use a transect?

Answer 9

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

Question 10

How could you make your results more reliable?

Answer 10

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

Question 11

what are enzymes?

Answer 11

protein consisting of big molecules

Question 12

what do enzymes work as?

Answer 12

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

Question 13

as catalysts, what do enzymes do and not do?

Answer 13

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

Question 14

What do digestive enzymes do?

Answer 14

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

Question 15

Why do digestive enzymes have to do this?

Answer 15

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

Question 16

What do carbohydrase enzymes do and give an example of one

Answer 16

They break down starch to glucose and fructose

e.g amylase

Question 17

What do protease enzymes do and give an example of one

Answer 17

They break down big proteins into amino acids

e.g pepsin

Question 18

What do lipase enzymes do and give an example of one

Answer 18

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

Question 19

Where is amylase made?

Answer 19

salivary gland
small intestine
pancreas

Question 20

Where is protease made?

Answer 20

stomach
pancreas
small intestine

Question 21

Where is lipase made?

Answer 21

pancreas

small intestine

Question 22

What is the process of digestion?

Answer 22

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.

Question 23

How are enzymes used commercially to make chocolate sweets?

Answer 23

-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

Question 24

Why is baby food so runny and pulpy?

Answer 24

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

Question 25

What happens if an enzyme gets too hot?

Answer 25

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.

Question 26

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

Answer 26

37 degrees celcius

Question 27

What enzymes are used in biological detergents?

Answer 27

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.

Question 28

What are the advantages of using enzymes in industry?

Answer 28

• 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.

Question 29

What are the disadvantages of using enzymes in industry?

Answer 29

• 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.