ENZYMES

Question 1

Active Site

Answer 1

The part of the enzyme into which the reactant molecule fits

Question 2

Catalyst

Answer 2

A substance that changes the rate of a reaction without being used up

Question 3

Denatured

Answer 3

The state of an enzyme when it has been irreversibly damaged and has changed shape. and doesn’t work anymore.

Question 4

Enzyme

Answer 4

A biological Catalyst. They can be used to break apart

molecules or build them up

Question 5

Inhibitor

Answer 5

A molecule that decreases the rate of enzyme-catalyzed reactions

Question 6

Lock and Key

Answer 6

A model of how enzymes work and the importance of their shape

Question 7

Optimum

Answer 7

The temperature and pH at which an enzyme-catalyzed reaction proceeds at the fastest rate

Question 8

Reactant

Answer 8

The molecule that binds to and reacts with the enzyme

Question 9

Respiration

Answer 9

The series of reactions that release energy from glucose, in the presence of oxygen

Question 10

Activation energy

Answer 10

The energy needed to start a chemical reaction

Question 11

Fermentation

Answer 11

The conversion of sugar to ethanol and carbon dioxide by enzymes in yeast

Question 12

Digestive System

Answer 12

Where large molecules are broken down into small soluble ones. These molecules
can be absorbed into the blood plasma in the small intestine (villi, microvilli) via diffusion/active
transport.

Question 13

Carbohydrates

Answer 13

Starch can be broken down into glucose using the amylase enzyme. This happens in
the mouth and small intestine. Glucose is the fuel for respiration. The process by which energy is
released.

Question 14

Lipids

Answer 14

Digestion happens in the small intestine. It is first broken down into smaller droplets by bile,
increasing the surface area for lipase, to then break it down into glycerol and fatty acids. Used as a
store of energy and can be used as a fuel for respiration. Also is used for cell membranes and
insulation.

Question 15

Proteins

Answer 15

• Broken down in the stomach using pepsin (protease enzyme). It can also be broken down
  in the small intestine using trypsin (another protease enzyme). Proteins break down into amino
  acids. To be used for growth and repair of cells and tissues. Can also be a fuel for respiration.
  Antibodies, enzymes and some hormones are made of protein.

Question 16

Substrate

Answer 16

The molecule/molecules that are being catalysed by the enzyme.

Question 17

Products

Answer 17

This is the molecule/molecules that are released at the end of the reaction.

Question 18

Amylase

Answer 18

• Enzyme made in the salivary glands and the pancreas. It works in the mouth and small
  intestine to break down starch into glucose.

Question 19

Protease

Answer 19

Enzyme made in pancreas and stomach lining. It works in the stomach and small intestine
to break down protein to amino acids.

Question 20

Lipase

Answer 20

Enzyme made in the pancreas. It works in the small intestine to break down small fat
droplets into glycerol and fatty acids.

Question 21

Salivary glands

Answer 21

Produces and secretes amylase.

Question 22

Stomach

Answer 22

Where protein is broken down by pepsin (protease enzyme which has an optimum pH at
pH2). It is acidic due to the presence of hydrochloric acid, which works to kill bacteria that have been
ingested.

Question 23

Pancreas

Answer 23

Makes all digestive enzymes to be secreted into the small intestine.

Question 24

Small intestine

Answer 24

Where protein, carbs and lipids are broken down into small soluble molecules. These
are absorbed through microvilli and villi (large surface area) into the blood plasma.

Question 25

Liver

Answer 25

Make bile

Question 26

Gall bladder

Answer 26

Stores bile

Question 27

Bile

Answer 27

Made in the liver and stored in the gall bladder. Emulsifies/Breaks down large fat droplets into smaller ones, to increase the surface area for lipase to work on. It also neutralises stomach acid.

Question 28

Large intestine

Answer 28

Where water is absorbed into the blood by osmosis and faeces begins to form.

Question 29

Rectum

Answer 29

Stores faeces.

Question 30

Anus

Answer 30

Where faeces is egested.

Question 31

Tissue

Answer 31

A group of specialised cells that have a similar structure and function working together. E.g heart/cardiac muscle

Question 32

Water

Answer 32

- Absorbed by osmosis in the large intestine. Used in the blood plasma for transporting substances. Is also essential for regulating temperature.

Question 33

Amino acids

Answer 33

The building blocks of proteins

Question 34

Carbohydrase

Answer 34

An enzyme that catalyses the breakdown of | carbohydrates such as starch into simpler sugars.

Question 35

Oesophagus

Answer 35

Muscular tube which pushes food from the mouth to the | stomach by using peristalsis.

Question 36

Teeth

Answer 36

Hard structures in the mouth that break up and grind food into smaller pieces to increase surface area for digestive enzymes to work on.

Question 37

Mouth

Answer 37

Hole where food is first placed to be chewed and | swallowed.

Question 38

Saliva

Answer 38

Liquid substance that lubricates food making it easier to swallow and contains amylase which begins the breakdown of carbohydrates.

Question 39

Digestion

Answer 39

The breakdown of large insoluble food molecules into small soluble food molecules that can be absorbed into the blood stream.

Question 40

Why can enzymes be described as biological catalysts?

Answer 40

Sometimes, enzymes can be described as biological catalysts because they seed up reactions like respiration and photosynthesis, and they make new proteins

Question 41

Why do enzymes only usually catalyse one reaction?

Answer 41

Enzymes only usually catalyse one reaction because the active site has a specific shape which only one substrate can fit in

Question 42

What does it mean when an enzyme has 'denatured'?

Answer 42

When an enzyme has denatured, it means that the enzyme has exceeded past its optimum pH and temperature which changes the shape of the active site meaning the specific substrate can no longer fit.

Question 43

List three places where amylase is made in the human body?

Answer 43

►Salivary glands ►Pancreas ►Small intestine

Question 44

What is the role of lipases?

Answer 44

The role of lipases are to break down lipids in to glycerol ad fatty acids

Question 45

Where is bile stored?

Answer 45

Bile is stored in the gall bladder before it is released in to the small intestine. it produced in the liver.

Question 46

Name the solution that you would use to test for the presence of lipids in a food sample.

Answer 46

Sudan III test is used to test for lipids in food.