chapter 2

Chapter 2: Nutrition

2.1) Classes of Food

1. Importance of food

a) Provides _______________ to carry out ________________________ and functions

b) Provides _______________ to do _________________

c) Growth of ____________________________ and repair ________________ tissues

d) Maintain good ______________ and fight _______________

2. Food are divided into _____ classes:

a) e)b) f)c) g)d)

3. Carbohydrate

a) Consists of carbon, ______________________________________________________

b) Includes sugar, _________________________________________________________

c) Smallest unit is _______________

d) Sources : ______________________________________________________________

e) Function : Provide _________________

4. Protein

a) Consists of carbon, ____________, _______________ and _______________

b) Some may have sulphur and phosphorus

c) Smallest unit is _________________________

d) Sources : ______________________________________________________________

e) Functions : (i) Growth and ________________ repair body tissues

(ii) Form enzymes, hormones and antibodies

(iii) Source of energy during _______________

(iv) Prevent _____________________

1 © Gabriel Chua, 2013

5. Fats

a) Consists of carbon, _______________ and _______________

b) Smallest unit are ___________________ and _____________________

c) Sources : ______________________________________________________________

d) Functions : (i) Source of ________________ (two times more than carbohydrate)

(ii) Heat __________________ (keeps body warm)

(iii) Protect __________________ from injury

(iv) Dissolve _______________________ vitamins (Vitamin A, D, E & K)

6. Vitamins

a) Organic compound needed in ___________________ amount.

b) Vitamin deficient can cause ________________ but excess of vitamins can become

_____________ to our body.

c) Divided into water soluble (Vitamin ____ & ___ ) and fat soluble (Vitamin ___, ___,

___ & ___ )

Vitamin Sources Effect of deficiencyA

B

C

D

E

K


7. Minerals

a) Inorganic compounds required in __________ amount.

b) Needed for proper growth and development.

c) Excess minerals are excreted through _____________ and ____________.

Mineral Sources Functions DeficiencyCalciumPhosphorus

Iodine

Iron

Sodium

Potassium

8. Fibre / Roughage

a) From ______________ in plants

b) Sources : ______________________________________________________________

c) Importance : Stimulate peristalsis

d) Lack of fibre causes _________________________________

9. Water

a) Average _____ glasses per day.

b) Lost a lot of water from ______________ and _____________

c) Sources : ______________________________________________________________

d) Importance : (i) Helps in __________________ and ________________ process


(ii) Controls body _____________

(iii) As _____________ for chemical reaction in body.

10. Food test

Food Test Procedure ObservationStarch 2cm3 starch solution + few

drops iodine Brown colour of iodine

turns _________________ colour

Glucose 2cm3 glucose solution + 2cm3 Benedict solution

Heat in water bath

Light blue colour of Benedict solution turns into _________________ precipitate

Protein 2cm3 albumen + 2 drops Million’s reagent

Heat in water bath

White precipitate is formed when Millon’s reagent is added.

White precipitate turns ____________ precipitate on heating

Fat Ethanol + 5 drops of cooking oil

Shake and let it settle for 2 minutes

________________ is formed

1 drop of cooking oil on filter paper

Allow to dry

_________________ is formed

2.2) Balanced Diet

1. Balanced diet is eating all classes of food in ____________ proportion.

2. Food pyramid


3. Factors determining balanced diet

Factor Example

Size

Jobs

Health

4. Calorific value

a) Calorific value is of food is the amount of _______________ released from 1 gram of a

particular food

b) The energy stored in food is measured in _______________ and ________________.

c) 1 cal = ___________ Joule

d) Kamal has his lunch which consists of nasi lemak (421 cal), curry (530 cal), roti canai

(275 cal) and a cup of Milo (316 cal). Calculate the calorific value of the lunch Kamal

had in kiloJoule.


2.3) Human Digestive System

1. The process of ________________________ food into soluble and diffusible molecules.

2. Carried out by _______________, a special protein produced by body to ____________

up chemical reactions in body.

3. 3 main types of digestive enzymes:

a) ________________________ (helps in carbohydrate digestion)

b) ________________________ (helps in protein digestion)

c) ________________________ (helps in fat digestion)

4. Non-digestive enzymes that help in digestion:

a) Hydrochloric acid (produced in ______________ )

b) Bile (produced in _________________ )

5. Human digestive system


Mouth (enzyme _____________________ )

Starch __________________

EsophagusFood is churned into ____________ via process ______________________

Stomach (gastric juice)Protease : Protein ____________________Hydrochloric acid (not enzyme):Stops action of enzyme from saliva and kills _____________________

Partially digested food in stomach is known as __________________

Duodenum (pancreatic juice + bile)Protease : Polypeptides ________________Amylase : Starch __________________Lipase : Fat _______________________ + _________________Bile (not enzyme): ________________ fat, neutralize ___________ from stomach

Small intestine Maltose _________________________Peptides _________________________Fat ________________________ + ___________________

6. Digestion in human

2.4) Absorption of Digested Food

1. Digested food (glucose, amino acids, fatty acids and glycerol) and vitamins are absorbed

by ________________ of __________________________ via diffusion into bloodstream.

2. Adaptations of small intestine

a) Has a lot of _______________ on its surface to increase the ______________________

b) Each villus has ____________ epithelial wall to enable diffusion of digested food.

c) There is a rich network of ________________________ in each villus.

d) ___________ (6m) for greater absorption.

e) Moist lining of epithelial wall allows digested food molecules to dissolve easily.


f) Peristalsis in small intestine enhances absorption

2.5) Reabsorption of Water and Defecation

1. Undigested food, minerals and water enters ______________ intestine.

2. Most water and minerals are ___________________ in the large intestine.

3. As water is absorbed, the mixture becomes solid waste, known as __________________.

4. Feaces is stored in _________________ before being expelled via anus. This process is

known as ____________________.

5. Lack of fibre will cause ____________________________.


chapter 2

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