The Mouth

Where does digestion start?The mouth

Where does digestion start?Use the information and skulls to find out about

different types of teeth.

DigestionDigestion is the breakdown of large insoluble molecules into small soluble molecules which can pass into the blood.

There are two types of digestion:1. Mechanical digestion (physical breakdown)2. Chemical digestion (enzyme breakdown)

Teeth – Mechanical Digestion(Stick in teeth diagrams under this heading)

Tooth type Shape FunctionLower incisors and horny pad Thin,

straight, sharp

Cut plant materialLower canine

and spacePremolar Sharp

ridges and hollows

Grind plant materialMolar

Tooth type Shape Function

Incisor Short, pointed Pull flesh from bones

Canine Long, pointed Pierce and hold prey

Premolar Sharp edges Slice flesh

Carnassial Big, sharp Shear flesh from bones

Molar Sharp edges Crush bones

Carnivore: eats only meatExample: Dog

Herbivore: eats only plant materialExample: Sheep

Tooth type Shape Function

Incisor Chisel shaped Bite and cut food

Canine Pointed Grip foodPremolar Blunt points

and hollowsCrush and grind foodMolar

Omnivore: eats both meat and plant materialExample: Human

Challenge...From the skull:

1. Is the animal carnivore, herbivore or omnivore?

2.What animal is it?

Write your answer on the mini white board.

You should be prepared to explain your answer.

HerbivoreOx

OmnivoreChimpanzee

CarnivoreOtter

CarnivoreBrown bear

OmnivorePig

CarnivoreBadger

Carnivore/PiscivoreDolphin

HerbivoreKoala bear

CarnivoreSeal

CarnivoreConstrictor (snake)

The MouthWhat two things happen in the mouth to start

digestion?

The Mouth

Digestion begins in the mouth.

• Teeth mechanically breakdown food into smaller pieces.

• Saliva chemically breaks down carbohydrates. Saliva is made in the salivary glands and contains the enzyme amylase.

The action of amylase

1

2

3SAM

SAM

Starch MaltoseAmylase

Past Paper Practice

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