digestive system-1

The digestive system
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Slide 1: Slide
BiologieMiddelbare schoolhavo, vwoLeerjaar 2

This lesson contains 22 slides, with interactive quizzes, text slides and 1 video.

time-iconLesson duration is: 30 min

Items in this lesson

The digestive system

Slide 1 - Slide

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2
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heart

large intestine

small intestine

stomach

lung

liver

brain

kidney

Slide 2 - Drag question

Digestion
Digestion: Breakdown of food molecules into small food molecules 

When food is digested it is absorbed  

Slide 3 - Slide

Big vs. Small
Big molecules -> Insoluble can not get through the gut wall

Small molecules -> Soluble can get through the gut wall

Slide 4 - Slide

Fases of digestion. Put them in the right order.
1
2
3
4
digestion
ingestion
absorption
egestion

Slide 5 - Drag question

FASES OF DIGESTION:
  • INGESTION
  • CHEMICAL AND MECHANICAL DIGESTION
  • ABSORPTION
  • EGESTION

Slide 6 - Slide

CHEMICAL DIGESTION:
  • BREAKING THE FOOD INTO EVEN SMALLER MOLECULES.
  • USING ENZYMES TO BREAK DOWN THE FOOD MOLECULES. 

Slide 7 - Slide

Chemical digestion
Enzymes: Important chemicals

Slide 8 - Slide

Work
Go to classroom and follow the link 'draw a model of the digestive system'.
  • Draw the organs of the digestive system
  • label the parts
  • add the functions

Slide 9 - Slide

Chemical digestion Step 1
  • starts in: the mouth 
  • the enzyme: amylase (a carbohydrase)
  • the liquid: saliva 
  • the nutrient: carbohydrates
  • the products: glucose 

The enzymes in your saliva start breaking down the carbohydrate molecules into glucose.

Slide 10 - Slide

Down the tube!
Oesophagus
Peristalsis: moving food down your oesaphagus (gullet)

Slide 11 - Slide

Why is your stomach rumbling? 
-peristalsis, muscle activity
- mechanical digestion

-Empty stomach and intestines make a louder sound!

Slide 12 - Slide

In your stomach
Digestive juices are added

  • Proteases -> digestion proteins -> amino acids
  • Hydrochloric acid -> acid PH, best for the enzymes + acidic environment also kills germs
  • Rennin (only babies) makes milk solid, stays in the stomach longer


Slide 13 - Slide

small           intestine

Slide 14 - Slide

In your small intestine
2 important liquids added in the first part (the duodenum)
  • Pancreatic juice (carbohydrases, proteases and lipases)
  • Bile from the liver, stored in the gall bladder
  • Bile is alkaline neutralises acid from the stomach
  • Bile emulsifies fats, increases surface area of fats lipase enzymes to act upon

Slide 15 - Slide

In your small intestine

Intestinal juice (carbohydrases, proteases, lipases) Complete digestion of food, made by the wall of the small intestine

Slide 16 - Slide

Slide 17 - Video

Ingestion
Mechanical digestion
Chemical digestion
MOVING THE FOOD INTO YOUR MOUTH
BREAKING THE FOOD INTO SMALLER PIECES.
THIS IS DONE BY YOUR TEETH
BREAKING THE FOOD INTO EVEN SMALLER PIECES.
USING ENZYMES TO BREAK DOWN THE FOOD MOLECULES. 

Slide 18 - Drag question

Amylase is an example of a
A
Carbohydrase
B
Lipase
C
Protease

Slide 19 - Quiz

During the break down of proteins you get:
A
glucose
B
amino acids
C
fatty acids

Slide 20 - Quiz

The environment of the stomach is
A
Acidic
B
Alkaline

Slide 21 - Quiz

Work

  • Read pages 54-58
  • Do questions digestive system#1 on classroom

Hand in your food diary OR lab report about food tests next lesson. 

Slide 22 - Slide