Biology - Enzymes

Question 1

What is the area of a root where many cells are dividing by mitosis?

Answer 1

Meristem

Question 2

How does oxygen move into and out of cells?

Answer 2

Diffusion

Question 3

What is used to test for the presence of protein?

Answer 3

Buiret Reagent

Question 4

What is used to test for the presence of starch?

Answer 4

Iodine Solution

Question 5

What is used to test for lipids/fatty acids?

Answer 5

Ethanol Emulsion Test

Question 6

What is used to test for protein?

Answer 6

Biuret Test

Question 7

What are enzymes?

Answer 7

Biological catalysts that speed up reactions in living organisms

Question 8

Where is enzyme amylase found and what does it break down?

Answer 8

It’s found in the saliva and small intestine, and it breaks down starch to small sugars, such as maltose

Question 9

Where is enzyme catalase found and what does it break down?

Answer 9

Most cells, but especially liver cells, and breaks down hydrogen peroxide made in many cells reactions to water and oxygen

Question 10

What is enzyme starch synthesise?

Answer 10

It’s found in plants, and is the synthesis of starch from glucose

Question 11

What is enzyme DNA polymeraise?

Answer 11

It’s found in the nucleus and is the synthesis of DNA from its monomers

Question 12

Which carbohydrate, found in foods such as pasta, is the substrate for amylase?

Answer 12

Starch

Question 13

What is the colour solution turns if it contains starch?

Answer 13

Black/blue

Question 14

What is the colour solution turns if it contains reducing sugars?

Answer 14

Orange/red

Question 15

What is the colour solution turns if it contains protein?

Answer 15

Purple

Question 16

What happens to a solution if it contains lipids (fats)?

Answer 16

A layer of emulsion forms on top

Question 17

What is part of a protein molecule broken down (digested) into?

Answer 17

Amino acids

Question 18

What is part of a starch molecule broken down (digested) into?

Answer 18

Glucose molecules

Question 19

What is part of a lipid molecule broken down (digested) into?

Answer 19

Fatty acids/glycerol

Question 20

How do you calculate the rate of reaction?

Answer 20

Product (mass/volume) / time

Question 21

What are optimum conditions?

Answer 21

Fastest rate of reaction

Question 22

What are the factors that influence enzyme activity?

Answer 22

pH, concentration and temperature

Question 23

Iodine Test for Starch?

Answer 23

1. 1 spatula of food sample on dish. (1cm3 if liquid)
2. Using a pipette, place a few drops of iodine solution into the food.
3. If starch present, then turns blue/black

Question 24

Benedict’s Test for Reducing Sugars?

Answer 24

1. 2 spatulas of food sample into test tube (1cm3 if liquid).
2. About 1cm3 depth of water should be added to the tube and stir.
3. Add an equal volume of Benedict’s solution and mix
4. Place the tube in a water bath (95) for a few minutes
5. If reducing sugars present, then turns orange/red

Question 25

Biuret Test for Proteins?

Answer 25

1. 1-2 spatulas of food sample into test tube (1cm3 if liquid)
2. Add 1cm3 depth of water and mix
3. Add an equal volume of potassium hydroxide solution to tube and stir
4. Add 2 drops of copper sulfate solution and stir
5. If protein is present, then turns purple

Question 26

Emulsion Test for Lipids?

Answer 26

1. 2 spatulas of food sample into test tube (1cm3 if liquid)
2. Add 2cm3 of ethanol to tube
3. Cover end of tube and shake
4. Allow contents to settle
5. Pour liquid from top of mixture into test tube 1/2 full of water
6. Record level of food and whether water is cloudy or clear