Biology CT1

Question 1

Why do cells need oxygen?

Answer 1

and glucose to respire

Question 2

What is an enzyme?

Answer 2

A biological catalyst.

Question 3

What is a catalyst?

Answer 3

Something that speeds up a chemical reaction without being used up.

Question 4

What is an amylase?

Answer 4

A type of enzyme in salva that is used to break down carbs and starch

Question 5

What does amylase break down carbs and starch into?

Answer 5

simple sugars (glucose)

Question 6

Why is an enzyme a specific shape?

Answer 6

it will only fit or work on certain substrates

Question 7

What is an enzyme made up of?

Answer 7

large proteins (amino acids)

Question 8

Where is protease found?

Answer 8

in the stomach

Question 9

What does protease break down?

Answer 9

proteins into amino acids

Question 10

Where is lipase found?

Answer 10

small intestine
stomach
pancreas

Question 11

What dceroloes lipase break down?

Answer 11

fats into glycerol

Question 12

Why are enzymes important for digestion?

Answer 12

-break down large food molecules
-small enough to cross cell membranes
-supply body with nutrients and sources of energy

Question 13

How many enzymes are in our bodies?

Answer 13

thousands

Question 14

What is known as synthesis?

Answer 14

building larger molecules from smaller subunits

Question 15

what are substrates?

Answer 15

the substances that enzymes work on

Question 16

What are known as products?

Answer 16

the substances that are produced

Question 17

What is the iodine test used to identify?

Answer 17

starch in foods

Question 18

What colour is the solution of iodine in potassium iodine

Answer 18

yellow-orange

Question 19

What colour does the solution go when iodine is in a food that contains starch

Answer 19

blue-black

Question 20

What does benedict’s test identify

Answer 20

reducing sugars, glucose, fructose

Question 21

1. Steps to benedict’s test

Answer 21

-mix equal parts of food solution and benedict’s solution in a test tube.

Question 22

2. Steps to benedict’s test

Answer 22

Place the test tube into water bath at 95 degrees for 5 mins

Question 23

What colour will show in the benedict’s test when the food contains no reducing sugars

Answer 23

blue

Question 24

What colour will show in the benedict’s test when the food contains little reducing sugars

Answer 24

green

Question 25

What colour will show in the benedict's test when the food contains some reducing sugars

Answer 25

Orange

Question 26

What colour will show in the benedict's test when the food contains lots reducing sugars

Answer 26

red

Question 27

What does the ethanol test identify?

Answer 27

fats and oils

Question 28

1. Steps to ethanol test

Answer 28

Half-fill a tube with ethanol. Add some crushed or liquid food and mix

Question 29

2. Steps to ethanol test

Answer 29

Pour some of the mixture into a tube of water and mix

Question 30

What happens to the solution when there are fats and oils present in the ethanol test

Answer 30

cloudy suspension near the top of the tube

Question 31

What does the biuret test identify?

Answer 31

protien

Question 32

1. Steps to biuret test

Answer 32

Mix equal volumes of food solution and dilute potassium hydroxide solution in a test tube.

Question 33

2. Steps to biuret test

Answer 33

Add a few drops of copper sulfate solution and mix

Question 34

What colour will the substance turn when protein is present.

Answer 34

from blue to lilac (pale purple)

Question 35

Define active site

Answer 35

the space in an enzyme where the substrate bonds with the substrate during an enzyme reaction

Question 36

Define denatured

Answer 36

When the active site of an enzyme changes shape so that the substrate can no longer fit

Question 37

What model shows how enzymes work?

Answer 37

lock-and-key model

Question 38

What does denatured mean?

Answer 38

The enzyme has changed shape.

Question 39

What is the graph called about enzymes?

Answer 39

A graph that shows enzyme activity across pH values

Question 40

What is it called at the top of the curve on an enzyme graph?

Answer 40

Enzyme optimal function

Question 41

What is visking tu