Food

Question 1

Need for food

Answer 1

Growth and repair of new/existing cells, tissues, organs
Food supplies materials and energy needed for metabolism

Question 2

Elements present in food

Answer 2

C, H, O, N, P, S
Carbon, hydrogen, oxygen, nitrogen, phosphorus, sulphur

Question 3

Elements present in salt

Answer 3

Na (Sodium), Cu (copper), Zn (Zinc)

Question 4

Trace Elements (found & needed in small quantities)

Answer 4

Fe (Iron), Cu (Copper), Zn (Zinc)

Question 5

Biomolecules

Answer 5

Chemicals found, made in living things

Question 6

The main biomolecules in food

Answer 6

Carbohydrates, fats (lipids), protein, water, vitamins, minerals

Question 7

Carbohydrates elements

Answer 7

C, H, O
General formula = Cx(H2O)y

Question 8

Carbohydrate Ratio

Answer 8

Cx(H2O)y C⁶H¹²O⁶

Question 9

Saccharide

Answer 9

Sugar unit

Question 10

Monosaccharide

Answer 10

Consist of 1 sugar unit
Sweet taste, soluble in water
E.g Glucose, Fructose

Question 11

Disaccharide

Answer 11

Consists of 2 monosaccharides joined together, sweet, soluble in water, e.g sucrose, maltose, lactose

Question 12

Polysaccharide

Answer 12

Many monosaccharides, insoluble, e.g starch, cellulose, glycogen (livers and muscles)

Question 13

Metabolic role of carbs

Answer 13

Gives energy needed for cell and bodily activities

Question 14

Structural role of carbs

Answer 14

Cellulose found in the structure of Plant Cell walls

Question 15

Elements in Lipids

Answer 15

C,H,O But not in the same ratio as carbs. Often less oxygen

Question 16

Lipid structure (Triglyceride)

Answer 16

→ Fatty Acid
Glycerol → Fatty Acid
→ Fatty Acid

Question 17

Phospholipid Structure

Answer 17

Phosphate
↓
____Glycerol____
↓ ↓
Fatty Acid Fatty Acid

Question 18

Metabolic role of lipids

Answer 18

For energy - Long term source

Question 19

Structural Role of lipids

Answer 19

Phospholipids form the structure of the cell membrane in cells
Heat insulation

Question 20

Elements in proteins

Answer 20

C, H, O, N, S, P

Question 21

Structure of protein

Answer 21

Long chains (Min 200) amino acids

Question 22

Peptide

Answer 22

Made of small no. of Amino acids (less than 20)

Question 23

Polypeptide

Answer 23

Has more than 20 amino acids but less than 200

Question 24

Fibrous proteins

Answer 24

Little or no folding, long and strong fibres. E.g Keratin

Question 25

Globular proteins

Answer 25

Show lots of folding. Forms rounded shapes. E.g Albunem in egg white

Question 26

Prions

Answer 26

Proteins that do not fold correctly. Can cause brain and nervous system diseases such as BSE in cattle

Question 27

Metabolic role of proteins

Answer 27

Used as enzymes to control reactions Antibodies are proteins that fight infections

Question 28

Structural role of proteins

Answer 28

Fibrous proteins such as keratin found in skin Myosin is found in muscles

Question 29

Water soluble vitamin

Answer 29

Vitamin C Found in fruit and veg. Role: forms connective tissue such as gums, skin, ligaments, heals as well, helps immune system function

Question 30

Fat soluble vitamin

Answer 30

Vitamin D (Fish oils, milk, liver) Helps absorb calcium - Deficiency disease - Rickets

Question 31

Calcium (Ca) Plant

Answer 31

Source: salts absorbed from soil Use: Helps form calcium pectate in cell walls

Question 32

Magnesium (Mg) Plant

Answer 32

Source: same as calcium Use: Part of the structure of chlorophyll

Question 33

Calcium (Ca) Animals

Answer 33

Source: Milk, Cheese Use: Forms teeth and bones

Question 34

Iron (Fe) Animals

Answer 34

Source: Liver, Meat, Green Veg Use: Part of structure

Question 35

Water Why is it essential to life

Answer 35

- Liquid in which all metabolic reactions take place - It provides the basis for the transport systems - It is the environment where many organisms live

Question 36

Importance of water in living things

Answer 36

Component of cytoplasm Good solvent Participates in chem reactions Good absorber of heat