Food

Question 1

Definition: Nutrition

Answer 1

The way in which organisms obtain and use food

Question 2

Autotroph

Answer 2

Autotrophs can make their own food by photosynthesis (Eg:) Plants

Question 3

Heterotroph

Answer 3

Heterotrophs: Cannot make their own food, they eat plants or animals (Eg:) Humans

Question 4

What does nutrition supply?

Answer 4

The materials for growth and reproduction in organisms

Question 5

Food gives what? to an organism for what?

Answer 5

Food gives nutrients to an organism for metabolism and continuity

Question 6

Nutrients are needed:

Answer 6

• To make chemicals needed for metabolic reactions
• As a source of energy
• Growth and repair of structures in an organism

Question 7

Most common chemical elements in living things:

Answer 7

C (carbon)
H (hydrogen)
O (oxygen)
P (phosphorus)
S (sulphur)
N (nitrogen)

Question 8

Dissolved salts/ Mineral elements

Answer 8

Na, Mg, Cl, K, Ca

body needs 100mg or more

Question 9

Trace elements

Answer 9

Zn, Cu, Fe

body needs less than 100mg

Question 10

Bio molecule definition

Answer 10

are chemicals made inside an organism

Question 11

Carbohydrate Elements

Answer 11

C H O

formula: Cx (H2O)y

Question 12

glucose formula

Answer 12

C6H12O6

Question 13

Monosaccharides

Answer 13

a carbohydrate composed of a single sugar unit

Example: glucose, fructose, galactose

Question 14

Disaccharides

Answer 14

a carbohydrate composed of two sugar units

Example: sucrose, maltose, lactose

Question 15

Polysaccharides

Answer 15

composed of multiple sugar units

Example:
Starch (plant glucose reserve)
Glycogen (glucose reserve of animals, stored in liver)
Cellulose (present in plant cell walls) (indigestible fibre)

Question 16

Sources of carbohydrates

Answer 16

pasta, potato, rice, bread, flour, sweets

Question 17

Structural role of Carbohydrates

Answer 17

Cellulose is the major component of rigid plant cell walls. Neighbouring plant cell walls are glued together forming a well built sturdy structure

Question 18

Metabolic role of carbohydrates

Answer 18

Glucose is made in photosynthesis (anabolic reaction)
Glucose is broken down and energy released in respiration (catabolic reaction)

Question 19

Use of carbohydrates

Answer 19

To supply and store energy

Question 20

Reducing sugar test

Answer 20

Heated Benedict’s Reagent
Blue before
Brick red of glucose is present

Question 21

Starch test

Answer 21

Iodine
Brown
Blue black if starch is present

Question 22

Lipids elements

Answer 22

C H O

Question 23

Difference between fats and oils lipids

Answer 23

Fats are solid and room temperature
Oils are liquid at room temperature

Question 24

Basic structure of a triglyceride

Answer 24

One glycerol
Three fatty acids

Question 25

Basic structure of a Phospholipid

Answer 25

One glycerol Two fatty acids One phosphate group

Question 26

Difference between triglyceride and phospholipid

Answer 26

Triglyceride: is made up of one glycerol and three fatty acids Phospholipid: is made up of one glycerol, two fatty acids and one phosphate group

Question 27

Sources of lipids

Answer 27

Meat, cream, butter, cod liver oil, sunflower oil

Question 28

Structural role of lipids

Answer 28

Energy store Fat surrounds our delicate organs protecting them (heart, kidneys) Insulation A modified form of lipid, phospholipid forms a bilayer of all cell membranes

Question 29

Metabolic role of lipids

Answer 29

Energy can be released from lipids by aerobic respiration Excess carbohydrate in our diet is converted to fat and stored

Question 30

Lipid Test

Answer 30

Brown paper Translucent spot evident if lipid is present Control: water: dries out

Question 31

Protein elements

Answer 31

C H O N sulphur, phosphorus

Question 32

Building blocks of protein

Answer 32

amino acids

Question 33

Many amino acids join together to form

Answer 33

Peptides

Question 34

Over 20 amino acids

Answer 34

poly peptides

Question 35

More than 200 amino acids

Answer 35

Protein

Question 36

Sources of protein

Answer 36

Meat, fish, eggs, milk

Question 37

Structural role of protein

Answer 37

Protein form structures such as: Keratin, found in hair and nails, which protects and insulates the body Myosin, found in muscle, muscle is present in the heart, in the wall of the arteries and veins etc

Question 38

Metabolic role of protein

Answer 38

Enzymes are proteins that control particular biochemical reactions. The metabolism of a cell depends on the set of active enzymes present in the cell at the time Some hormones are made of protein

Question 39

Test for Proteins

Answer 39

Bliuret test Sodium Hydroxide (colourless) Copper Sulphate (blue) Turns purple/ lilac is protein is present

Question 40

fibrous

Answer 40

Collagen (bones and tendons) Keratin (hair and nails) Myosin (muscle)

Question 41

Globular

Answer 41

Enzymes (biological catalysts) Haemoglobin (red blood cells) Hormones (chemical messengers)

Question 42

Role of Vitamins

Answer 42

Health cell production tissue growth

Question 43

Vitamin C sources

Answer 43

Oranges, lemons, limes, blackcurrant

Question 44

Use of Vitamin C

Answer 44

Vitamin C is needed to form skin, gums Role in fighting infection

Question 45

Deficiency in Vitamin C

Answer 45

Scurvy

Question 46

Symptoms of scurvy

Answer 46

Poor healing of skin Bruising poor gums with loose teeth

Question 47

Vitamin D sources

Answer 47

Liver, fish, oils, milk ALSO made in skin (UV rays)

Question 48

Use of Vitamin D

Answer 48

Need to absorb calcium from our intestines into the blood

Question 49

Deficiency in Vitamin D

Answer 49

Rickets, osteomalacia

Question 50

Symptoms of Osteomalacia

Answer 50

weak, deformed, brittle bones

Question 51

What are minerals essential for?

Answer 51

metabolism

Question 52

Minerals needed by plants

Answer 52

Calcium (support to cell walls) Magnesium (to make green pigment chlorophyll, essential for photosynthesis)

Question 53

Minerals needed by animals

Answer 53

Calcium (formation of bones and teeth) Iron (red pigment haemoglobin (which carries oxygen) (prevents anaemia)

Question 54

Importance of water in living things

Answer 54

Component of the cytoplasm and body fluids of living organisms. Excellent solvent which allows, 1. Cell reactions to take place 2. transport of, vitamins, minerals etc, of hormones, of waste products (CO2)

Question 55

Metabolic role of water

Answer 55

water plays a key role in many metabolic reactions (respiration and photosynthesis)

Question 56

Water moves

Answer 56

in and out of cells very easily giving them the correct shape

Question 57

Water has a specific high heat capacity

Answer 57

This means that water is difficult to warm up or cool down. This means that water tends to maintain a fairly constant temperature. Organisms living in water or mainly composed of water tend to have stable temperatures, this allows their reactions to take place at constant rated

Question 58

metabolism definition

Answer 58

the sun of all chemical reactions in the body

Question 59

anabolic reaction

Answer 59

form larger molecules from smaller ones anabolic reactions require energy and enzymes to take place. Example: Photosynthesis

Question 60

Catabolic reactions

Answer 60

Break down large molecules to form smaller ones Catabolic reactions need enzymes but they release energy Example: Respiration