Chapter 3.3 The Chemistry of food

Question 1

What are the main compounds that make up the structure of a cell?

Answer 1

carbohydrates
lipids
protein

Question 2

What do carbohydrates do?

Answer 2

-Provide us with fuel that makes all other reactions of life possible

Question 3

What chemical elements do carbohydrates contain?

Answer 3

carbon
hydrogen
oxygen

Question 4

All carbohydrates are made up of units of _________

Answer 4

sugar

Question 5

Small carbohydrates units (one and two units) are referred to as _________

a carbohydrates with a single sugar unit?

Name a carbohydrates with a two sugar unit?

Answer 5

simple sugars

glucose

sucrose

Question 6

Complex carbohydrates are made up of ___________

Give 2 examples of complex carbohydrates?

Answer 6

long chains off simple sugars bonded together.

starch and cellulose

Question 7

Simple carbohydrates turn ______________ solution brick __________on heating.

Answer 7

Blue Benedict

red

Question 8

Complex carbohydrates turn ________________ solution ___________________.

Answer 8

yellow-red iodine

blue-black

Question 9

List some food rich in carbohydrates

Answer 9

bread
potatoe
rice
pasta

Question 10

Most carbohydrates you eat will be broken down to ________ used in cellular respiration to provide _________ for __________ in your cells

Answer 10

glucose
energy
metabolic reactions

Question 11

What are Lipids?

Answer 11

fats (solids) and oils (liquids) . The supply your body with energy

Question 12

What chemical elements are lipids made up of?

Answer 12

carbon
hydrogen
oxygen
(same as carbohydrates)

Question 13

All lipids are INSOLUBLE/SOLUBLE in water

Answer 13

insoluble

Question 14

Lipids are made up of three molecules of ______________ joined to a molecule of _____________. The ________ are always the same but the _______________vary.

Answer 14

fatty acid
glycerol
glycerol (same)
fatty acids (vary)

Question 15

Name some lipid rich foods?

Answer 15

Olive and corn Oil
butter
margarine
cheese
cream

Question 16

What are proteins used for ?

Answer 16

building up the cells and tissues of your body, as well as the basis of all your enzymes.

Question 17

What percentage of your bodies mass is protein?

Answer 17

15 to 16%

Question 18

What part of the body is protein found in?

Answer 18

hair
nails
muscles
enzymes

Question 19

What chemical elements are proteins made up of?

Answer 19

carbon
oxygen
hydrogen
nitrogen

Question 20

Name some protein rich foods?

Answer 20

fish
meat
cheese

Question 21

Protein molecules are made up of long chains of small units called?

Answer 21

amino acids

Question 22

Long chains of amino acids that make up protein are folded, coiled and twisted to make specific _____________. It is these specific _________ that enable other molecules to fit into the __________.The bonds that hold proteins in their 3D shapes are very sensitive to _____and _____ and can be easily broken (DENATURED)

Answer 22

3 d shapes.

shapes
protein
temperature and pH

Question 23

What functions do proteins carry out in your body?

Answer 23

• structure components of tissues such as muscles and tendons
  -hormones such as insulin
  antibodies which destroy pathogens and are part of the immune system
  -enzymes which act as catalysts

Question 24

What are the two tests used to identify carbohydrates

Answer 24

-iodine test for starch. (yellow red iodine solution turns blue-black if starch is present
- benedicts test for sugars (blue benedict solution turns brick red on heating if a sugar such as glucose is present
)

Question 25

What are the two tests used to identify protein

Answer 25

-Biuret test - blue biuret reagent turns purple if protein is present

Question 26

What are the two tests used to identify lipids

Answer 26

ethanol test - ethanol added to a solution gives a cloudy white layer if a lipid is present. Ethanol is highly flammable and harmful