Food and biolomolecules

Question 1

what are the two main functions of food?

Answer 1

1. To provide organisms with energy
2. To provide the materials for growth and repair of cells and tissues

Question 2

The elements of food

Answer 2

Carbon, hydrogen, oxygen, nitrogen, sulphur and phosphorous

Question 3

the trace elements of food

Answer 3

Fe, Cu, Zn

Question 4

Salts in food

Answer 4

Na, Mg, Cl, K, Ca

Question 5

name 5

Biomolecules

Answer 5

carbohydrates, lipids, proteins, vitamins and water

Question 6

what are carbohydrates (saccharides) composed of?

Answer 6

C, H, O

Question 7

general formula of carbohydrate

Answer 7

Cx(H2O)y

Question 8

monosaccharides

Answer 8

single sugar units, eg. glucose

Question 9

disaccharides

Answer 9

two sugar units, eg. sucrose, maltose

Question 10

polysaccharides

Answer 10

many sugar units, eg.
1. starch- plant storage
2. cellulose- plant structural
3. glycogen- animal storage
4. chitin- animal structural

Question 11

What are lipids (fats and oils) composed of?

Answer 11

C, H, O but not in the same proportion as sugars

Question 12

triglyceride

Answer 12

smallest lipid- three fatty acid and one glycerol molecule

Question 13

phospholipid

Answer 13

a lipid with one of its fatty acids replaced with a phosphate group

Question 14

fats

Answer 14

solid at room temp

Question 15

lipids

Answer 15

liquid at room temp

Question 16

sources of lipids in diet

Answer 16

fat, butter, red meat, oil

Question 17

sources of carbohydrates in diet

Answer 17

SOURCES: bread, pasta, rice

Question 18

proteins made up of?

Answer 18

C, H, O, N and sometime sulphur

Question 19

basic unit of protein?

Answer 19

amino acid

Question 20

sources of protein in diet

Answer 20

lean meat, fish, eggs

Question 21

structural role of carbohydrates

Answer 21

cellulose in plant cell walls, chitin in fungi cell walls

Question 22

structural role of proteins

Answer 22

myosin in muscle, collagen in hair

Question 23

structural role of lipids

Answer 23

phospholipids found in cell membrane

Question 24

metabolic role of carbs

Answer 24

primary sources of energy - glucose

Question 25

metabolic role of proteins

Answer 25

enzymes control chemical reactions in cells

Question 26

metabolic role of lipids

Answer 26

release of energy and long term energy storage

Question 27

metabolic role of vitamins

Answer 27

essential organic catalysts of metabolism eg:
c— soluble in water— skin, bone, blood— citrus fruits— scurvy
D— soluble in fat — absorbs calcium— dairy, sunlight — rickets

Question 28

Minerals needed by plants

Answer 28

calcium- to make cell walls
magnesium- to make chlorophyll
nitrates- make proteins
phosphates- make ATP, DNA

Question 29

Minerals needed by animals

Answer 29

calcium- make bones and teeth
iron- make haemoglobin
sodium- regulate water content of cells and blood

Question 30

use of water

Answer 30

-maintain constant temp
-sweating
-moves material in and out of cells
-controls cell shape osmosis
-reactant in photosynthesis