2 c Biological molecules

Question 1

What are the 3 main molecules in organisms

Answer 1

-Carbohydrates
-Proteins
-Lipids

Question 2

Chemical elements of carbohydrates

Answer 2

Carbon, oxygen, hydrogen

Question 3

Chemical elements of protein

Answer 3

Carbon, oxygen, hydrogen, nitrogen (sometimes others)

Question 4

Chemical elements of lipids

Answer 4

Carbon, hydrogen, oxygen

Question 5

What are glucose and fructose

Answer 5

Monosaccharides

Question 6

What happens when glucose is broken down

Answer 6

It releases a lot of energy

Question 7

How are disaccharides made

Answer 7

Two monosaccharides joint together

Question 8

How is maltose formed

Answer 8

Two glucose molecules

Question 9

How is sucrose formed

Answer 9

One glucose & one fructose molecule

Question 10

How is a polysaccharide formed

Answer 10

Lots of monosaccharides joint together

Question 11

Examples of polysaccharides

Answer 11

Starch, glycogen, cellulose

Question 12

Why are polysaccharides useful as storage molecules

Answer 12

Theyre insoluble

Question 13

What are most of lipids made up of in the body

Answer 13

Triglycerides

Question 14

What are lipids divided into

Answer 14

Fats (solid at room temperature)
Oils (liquid at room temperature)

Question 15

What are proteins made of

Answer 15

Long chains of amino acids

Question 16

How many amino acids are there

Answer 16

20

Question 17

Examples of proteins

Answer 17

Enzymes, haemoglobin, ligaments & keratin

Question 18

What solution is added to test for glucose

Answer 18

Benedicts solution

Question 19

What colour change would be positive for test for glucose

Answer 19

Blue to orannge / brick red

Question 20

What is used to test for starch

Answer 20

Iodine solution

Question 21

What colour change would be a positive test for starch

Answer 21

orange-brown to blue-black

Question 22

What solution is used to test for proteins

Answer 22

Biuret solution

Question 23

What colour change would be a positive test for proteins

Answer 23

Blue to purple

Question 24

What liquid is used to test for lipids

Answer 24

Ethanol

Question 25

What would form to signify a positive test for lipids

Answer 25

Cloudy emulsion

Question 26

Name the safety measures for
-Biuret solution & iodine
-Sodium hydroxide
-Ethanol

Answer 26

-Irritants to the eyes
-Corrosive
-Flammable

Question 27

What are enzymes

Answer 27

Biological catalyst that speeds up the rate of reaction without being changed

Question 28

Why are enzymes necessary

Answer 28

They maintain the reaction speeds of metabolic reactions

Question 29

How are enzymes specified to one particular substrate

Answer 29

They have an active site which has a specific shape

Question 30

What is the name when a substrate moves into the active site

Answer 30

enzyme-substrate complex

Question 31

What’s the optimum temperature for enzymes

Answer 31

37ºC

Question 32

What will happen if the temperature is too high for enzymes

Answer 32

The bonds that hold the enzymes together will break: Denature

Question 33

What happens during denaturation

Answer 33

The active site changes shape, the substrates no longer fit. Its irreversible

Question 34

Why do enzymes work less at lower temperatures

Answer 34

The molecules have less kinetic energy so they move slower and there’s less collision

Question 35

What is the optimum pH for most enzymes

Answer 35

7

Question 36

What happens if the pH is too high or too low for the enzyme

Answer 36

The bonds can be disrupted/destroyed; denaturation

Question 37

What are the factors that affect the activity of enzymes

Answer 37

-Temperature
-pH