Intestinal juice

contain

Carbohydrase, protease

Digestion of protein starts at

K

Constipation

Need to eat more

vegetables

Calculate the amount of milk should take to get 900mg of calcium.

Milk (per 100 mL)Energy 272 kJCarbohydrate 4.8gProtein 3.4gFat 3.8gCalcium 110 mg

900/110*100 = 818 mL

Albustix paper

Positive result

Yellow to Green

Calcium

Deficiency disease

Rickets

Which part stores faeces?

N

Scurvy

Need to eat more

Fruit, vegetable

Anaemia

Need to eat more

Meat, liver

Girls needs more iron than boys

because

Girls loss blood in menstruation. They need more iron to produce

blood

Teenager need more protein

because

They need more protein for growth

What food substances are absorbed by Y?

Water soluble substances: glucose, amino acid, vitamin C, minerals, water

Y

What is B?

Gall bladder

Glucose

Food test

Clinistix paper

Intestinal juice

Secreted by

Intestinal gland in small intestine

Spot test

Positive result

Translucent spot disappeared

Anaemia

Not enough

Iron

State two features of X that allow it to absorb food substances easily.

X is finger like to increase surface area to absorb food.There are lots of X in small intestine to increase surface

area to absorb food.

X

Vitamin C

Function

Forming connective tissue

Mouth

Digestive juice

Saliva

Chemical digestion

by

Digestive enzymes

What is the fluid inside Z?

Lymph

Z

Mouth

Physical digestion by

Chewing of teeth

Bile

Physical digestion by

Emulsify fat to oil droplet to increase surface area for lipase to act on

Small intestine

Digestive juice

Intestinal juice

Calculate the amount of milk should take to get 3600kJ ?

Milk (per 100 mL)Energy 272 kJCarbohydrate 4.8gProtein 3.4gFat 3.8gCalcium 110 mg

3600/272*100 = 1323.5mL

Small intestine is long

because

It can provide more time to digest and absorb food substances.

Bile

contain

Bile salt, hydrogencarbonate salt, bile pigment

Lipase

Can be found in

Pancreatic juice

Pancreatic juice

contain

Amylase, protease, lipase,Hydrogencarbonate salt

Gastric juice

contain

Protease, hydrochloric acid

What is Z?

Lacteal

Z

Iron

Function

Form haemoglogin

Amylase

Can be found in

Saliva, pancreatic juice

Food move in alimentary canal

by

peristalsis

Which part is acidic?

stomach

Energy requirement depands on

Age, gender, occupation, body status

What part does digestion of lipid

start?

D

Vitamin A

Function

Form pigment for night vision

Teenager need more protein

because

They need more protein for growth

Teenager need more calcium

for

The growth of bones and teeth

Villus

shape

Finger like to increase surface area for absorption

What is Y?

Blood capillaries

Y

Starch

Food test

Iodine test

Matching

Glucose . .ProteinGlycerol . .StarchAmino acid. .LipidFatty acid .

Saliva

Secreted by

Salivary gland

What is ingestion?

Food is taken in through the mouth.

Bile

Secreted by

Liver

What are the 7 types of food substances?

carbohydrate 碳水化合物protein 蛋白質lipid 脂質mineral 礦物質vitamin 維生素dietary fibre 食用纖維water

What part is ingestion take

place?H

Stomach

Physical digestion by

Churning of muscle

The average energy requirment of Sam is 12000kJ but his average daily intake is 14000 kJ. Explain how his

diet affects his body weight.

The energy intake (14000kJ) of the man is more than his daily need (12000 kJ) . Excess energy will be convert to fatty tissue and stored under skin and around internal organs. His weight increases / he will be overweight

Saliva

contain

Salivary amylase, water

What is E?

Ileum

Dietary fibre

Deficiency disease

Constipation

Vitamin D

Deficiency disease

Rickets

Constipation

Not enough

Dietary fibre

Constructive worker need more energy

because

They need more energy for stronger muscle contraction

Night blindness

Need to eat more

Fish liver oil, carrot

Rickets

Need to eat more

Dairy product, Cheese, Milk

Glucose

Function

Produce energy by respiration

What is egestion?

The undigested materials are removed from the body as faeces.

What is assimilation?

The absorbed food molecules are taken up by cells for metabolism.

What are the importance of food?

Providing energy for doing activities and keeping us warm;Providing raw materials for growth and repair of body tissues;maintaining health

What is N?

Rectum

Which part absorbs the largest amount

of nutrient?

E

Iron

Deficiency disease

Anaemia

Gastric juice

Secreted by

Gastric gland in stomach

Pregnant women need more protein

because

They need more protein for foetus growth

Rickets

Not enough

Calcium/ Vitamin D

Pancreatic juice

Secreted by

Pancreas

What part is acidic?

K

Scurvy

Not enough

Vitamin C

Clinistix paper

Positive result

Red to purple

Peter: Weight:50kg, Daily energy requirements: 11500 kJ

Calculate Peter’s daily energy requirement per unit body weight (kJ/kg)?

11500/50 = 230 kJ/kg

Lipid

Food test

Spot test

What is absorption?

The digested food molecules enter the circulatory system.

What food substances are absorbed by Z?

Lipid soluble substances: fatty acid, glycerol, vitamin A, D, E, K

Z

Vitamin C

Food test

DCPIP test

Baby need more energy per unit body weight

because

The relative surface area of baby is large, they need more energy to

produce heat to compensate heat loss

What is digestion?

Food is broken down into soluble and simple molecules.

DCPIP test

Positive result

Blue to colourlessDecolorized

Reducing sugar

Food test

Benedict’s test

Blood in Y will first transport to….through……

liver; hepatic portal vein

Y

What is the fate of excess protein?

Excess amino acids cannot stored and will be broken down in liver by deamination :(i) Urea formed is carried via the bloodstream to the kidneys and is excreted in the urine.(ii) The remaining part of the amino acid is converted to glycogen and stored in liver.

Benedict’s test

Positive result

Brick red precipitate

Liver

Digestive juice

Bile

Protein

Food test

Albustix paper

Stomach

Digestive juice

Gastric juice

What is X?

Villus

X

Iodine test

Positive result

Brown to blue black

Protein

Functions

Growth and repair, produce enzyme, hormone,

haemoglobin

Lipid

Function

Produce energy, shock absorber, heat insulator

Protease

Can be found in

Gastric juice, pancreatic juice, intestinal juice

Calcium

Function

Form bones and teeth

Water

Function

As solvent, for transport, heat loss by sweating

Physical digestion

function

Increase surface area of food for digestive enzyme to act on

Vitamin C

Deficiency disease

Scurvy

Vitamin A

Deficiency disease

Night blindness

What is the fate of excess glucose?

Excess glucose is converted to glycogen by the liver for

storage. Some of the excess glucose is converted to

lipid.

Calculate the energy in 300mL milkMilk (per 100 mL)

Energy 272 kJCarbohydrate 4.8gProtein 3.4gFat 3.8gCalcium 110 mg

272*3 = 816 kJ

What is L?

Pancreas

Villus

number

Large number to increase surface area

Dietary fibre

Function

Stimulate peristalsis in gut (intestine)

Night blindness

Not enough

Vitamin A

What is the fate of excess protein?

Excess amino acids cannot stored and will be broken down in liver by deamination :(i) Urea formed is carried via the bloodstream to the kidneys and is excreted in the urine.(ii) The remaining part of the amino acid is converted to glycogen and stored in liver.

Suggest a reason why construction workers require more energy than

office clerks.

Construction worker need more energy for stronger muscle contraction.

Explain how stomach is protected from digestion.

Mucus can protect stomach from digestion

The human digestive system consists of

Alimentary canal and Digestive glands

Pancreas

Digestive juice

Pancreatic juice

Vitamin D

Function

Help Calcium absorption