Enzymes

Question 1

What are enzymes?

Answer 1

Enzymes are all proteins that act as BIOLOGICAL CATALYSTS within the body

Question 2

What is a catalyst?

Answer 2

A catalyst is a substance which increases the speed of a reaction without being CHANGED or USED UP in the reaction

Question 3

Why do enzymes have special shapes?

Answer 3

Enzymes have special shapes so they FIT onto the substance involved in a reaction.

Enzymes are really fussy and usually only catalyse one reaction.

This is because each enzyme will only fit one particular substance.

Question 4

What two things do enzymes need in order to function?

Answer 4

The right temperature and PH.

The temperature can change the rate of an enzyme catalyst reaction.

PH needs to be just right as if its too high or too low the PH interferes with the BONDS holding the enzyme together.

Question 5

Explain how a change of temperature can affect the rate of an enzyme catalysed reaction.

Answer 5

A higher a temperature increases the rate at first.

If it gets too hot some of the bonds holding the enzyme together break. This destroys the enzyme’s special shape and so it wont work any more.

Question 6

What is the ideal temperature for enzymes in the human body?

Answer 6

37c

Question 7

What is the ideal PH for enzymes

Answer 7

It’s ofetn neutral PH7

However some enzymes such as PEPSIN it works best at PH2 as they break down proteins in the stomach which is very acidic

Question 8

What do digestive enzymes do?

Answer 8

They break down big molecules into smaller ones.

BIG MOLECULES = starch, protein and fats

SMALL MOLECULES = sugars, amino acids, glycerol and fatty acids

Question 9

Name the enzyme that breaks down starch and was it broken down into?

Answer 9

This is known as the Amylase Enzyme and it breaks down stach into sugars such as MALTOSE and DEXTRINE

Question 10

Where in the body is Amylase Enzyme created?

Answer 10

The salivary gland, pancreas and the small intestine

Question 11

Name the enzyme that breaks down proteins and what is it broken down into?

Answer 11

This is known as PROTEASE Enzyme and it breaks down proteins into amino acids

Question 12

Where in the body is the emzyme Protease produced?

Answer 12

It is produced in the stomach, pancreas and small intestine.

Question 13

What enzyme breaks down lipids and what is it broken down into?

Answer 13

It is the Lipase Enzyme and it breaks down lipids into glycerol and fatty acids

Question 14

Where in the body is lipase enzymes produced?

Answer 14

In the pancreas and small intestine

Question 15

Enzymes in the stomach work in acidic conditions but in the intestine enzymes wok better in alkaline conditions.

What substance neurtalises the acid and makes it more alkaline in the intestine?

Answer 15

Bile

Question 16

Where is bile produced and where is it stored?

Answer 16

Bile is produced in the liver and it is stored in the gall bladder

Question 17

What does bile do to fats?

Answer 17

It emulsifiers them which means it breaks them down into small droplets

Question 18

Do you know the digestive enzyme diagram?

Answer 18

Ok then please draw it now.

Here’s a clue:

1. Salivary glands produce AMYLASE ENZYME in saliva.
2. Food goes down the Gullet.
3. It hits the stomach which prodcues the PROTEASE ENZYME called PEPSIN
4. Stomach also produces hydrochloric acid which KILLS bateria and provides the right PH for PROTEASE enyme to work
5. Liver produces BILE
6. GALL BLADDER stores Bile
7. Pancrease produces PROTEASE, AMYLASE and LIPASE
8. Small intestine produces PROTEASE, AMYLASE and LIPASE
9. Large intestine is where excess water is absorbed from the food
10. Rectum is where the faeces is stored before they are poohed out

Question 19

Is respiration breathing in and out?

Answer 19

No it is the PROCESS of RELEASING ENERGY from the breakdown of glucose.

It happens in animals and plants

Question 20

What do you call respiration which uses oxygen?

Answer 20

Aerobic respiration

Question 21

Aerobic respiration has an equation what is it?

Answer 21

Glucose + Oxygen = CO2 + water + energy

Question 22

Name another type of respiration apart from aerobic respiration

Answer 22

Anaerobic respitaion which produces less energy that aerobic respiration but it does not need oxygen

Question 23

Respiration releases energy for all kinds of things. Give some examples

Answer 23

1. To build up larger molecules from smaller ones
2. In animals to allow the muscles to contract
3. In mammals and birds to maintain body temperature
4. In plants to build sugars, nitrates and other nutrients into amino acids

Question 24

Explain how exercise gets you out of breath

Answer 24

1. An increase in muscle activity requires more glucose and oxygen to be supplied to the body.
2. Extra CO2 needs to be removed from the muscle cells
3. To get more oxygen and glucose to the muscle and to remove the extra CO2 the blood needs to flow faster and this means the heart must beat faster.
4. To get more oxygen into the body breathing rate also increases

Question 25

What is glycogen?

Answer 25

Glycogen is glucose which is stored as glycogen in the liver.

Muscles also have its own store of glycogen.

When exercising if the muscle runs out of glucose it can tap into the stored glycogen for more energy.

Question 26

What does the word “anaerobic” mean?

Answer 26

It means “without oxygen”

Question 27

Provide the equation for anaerobic respiration

Answer 27

Glucose - Energy + Lactic Acid

Question 28

Give an example of aerobic respiration and anaerobic respiration

Answer 28

Aerobic respiration is when you run

Anaerobic respiration is when you weight train

Question 29

What is the difference between aerobic respiration and anaerobic respiration?

Answer 29

Anaerobic uses less energy and builds up lactic acid which can be painful.

Anaeobic does allow you to keep using your muscles.

Question 30

Anaerobic respiration leads to an ______ debt

Answer 30

Oxygen debt

Question 31

What is meant by oxygen debt in terms of anaerobic respiration?

Answer 31

As anaerobic respiration does not use oxygen there is an oxygen debt.

This means you breath hard for a while after you stop exercising so you can get more oxygen into the blood.

This is necessary as the blood takes the oxygen to your muscles to remove the lactic acid by OXIDISING it to CO2

Whilst there are high evels of CO2 and lactic acid are present the pulse and breathing rate stays high to try and rectify the problem.

Question 32

Look at mummy’s washing powder. Does it say it is biological?

What does this mean?

Answer 32

It means that the washing pwder contains “biological” ingredients such as protein digesting enzymes such as PROTEASES and fat digesting enzymes LIPASES

Question 33

How do biological washing powders work?

Answer 33

THey contain enzymes (PROTEASES and LIPASES) which are ideal for removing stains like food or blood.

They are also more effective at lower temperatures (30c).

Question 34

How do enzymes work with baby food?

Answer 34

The proteins in some baby foods are “pre-digested” using protein-digesting enzymes (PROTEASES).

Carbohydrate-digesting enzymes (carbohydrases) can be used to turn starch syrup into sugar syrup.

Question 35

Name 4 advantages of using enzymes in industry

Answer 35

1. They are specific so they only catalyse the reaction you want.
2. Using lower temperatures and pressures means lower cost as it saves energy.
3. Enzymes work for a long time so you can continually use them.
4. They are biodegradable so cause less environmental pollution.

Question 36

Name 4 disadvantages of using enzymes in industry

Answer 36

1. People may be allergic to certain enzymes
2. Enzymes can be denatured by even a small increase in temperature so must be tightly controlled.
3. Enzymes can be expensive to produce
4. Contamination of enzymes with other substances can affect reaction