3.4 Organising digestion

Organising digestion
3.4
Chapter 3: Break it down?
1 / 20
volgende
Slide 1: Tekstslide
BiologyMiddelbare schoolvwoLeerjaar 2

In deze les zitten 20 slides, met interactieve quizzen, tekstslides en 1 video.

Onderdelen in deze les

Organising digestion
3.4
Chapter 3: Break it down?

Slide 1 - Tekstslide

Deze slide heeft geen instructies

Learning goals of this lesson
  • What are the organs and theri functions of the digestive system?
  • What is peristalsis, digestion and emulsification?
  • Which digestive juices does our body produce and what do they do?

Slide 2 - Tekstslide

Deze slide heeft geen instructies

Organs in your digestive system
mouth
oesophagus
stomach
duodenum
small intestines
large intestines 
rectum 
anus

Slide 3 - Tekstslide

Deze slide heeft geen instructies

Slide 4 - Video

Deze slide heeft geen instructies

In your mouth
Your teeth, tongue and chewing mussles are mixing the food, you ate with saliva -> amylase starts to digest the startch in your food.
The oesophagus moves the food towards your stomach. 
The mussles in the oesopagus using peristalsis to transport the food.

Slide 5 - Tekstslide

Deze slide heeft geen instructies

Oesophagus
No digestive juices
Peristalsis to move the food down

Slide 6 - Tekstslide

Deze slide heeft geen instructies

Slide 7 - Tekstslide

Longitudinal mussles push the food bolus further down
Circular mussles are closing and relaxing arround the food bolus.
What is peristalsis?

Slide 8 - Open vraag

Deze slide heeft geen instructies

the Stomach
It is a muscular bag where food is churned by the mussles.
this is mechanical digestion. -> reason is to increase the surface area of the food.

But in the stomach also chemical digestion takes place.
The stomach produces HCl (hydrochloric acid) and Pepsinogen.
The pepsinogen turns in an acid environment into pepsin. And pepsin breaks down the fat in your food.
Protease breaks down the proteins in your food.

Slide 9 - Tekstslide

bolus - foodpart with saliva or other enzymes which is travelling through your digestive system

Pylorus
a circular muscle, which closes the stomach
It is between the stomach and the duodenum

Slide 10 - Tekstslide

Deze slide heeft geen instructies

the Duodenum
Latin for twelve fingers.
Digestion with two juices.
-> pancreatic juice
-> bile which is made in the liver.

Slide 11 - Tekstslide

Deze slide heeft geen instructies

Pancreatic juice
Made in the pancreas.
Mixture of different enzymes.
These enzymes break down carbohydrates, proteins and fats.
These juices appear in the duodenum.

Slide 12 - Tekstslide

Deze slide heeft geen instructies

Why is bile neccesary for you digestion?

Slide 13 - Open vraag

Deze slide heeft geen instructies

Bile
Bile is produced in the liver.
Bile is stored in the galbladder.

Slide 14 - Tekstslide

Deze slide heeft geen instructies

What is the reason why from a patient where the galbladder is removed, may not eat so much fat anymore?

Slide 15 - Open vraag

Deze slide heeft geen instructies

Small intestines
digestion is completed
enzymes in interstinal juices
break down of undigested carbohydrates and proteins
All end products of digestion are absorbed into the bloodstream

Slide 16 - Tekstslide

Deze slide heeft geen instructies

Small intestines
the lining isn't smooth
millions of small villi
The reason is to absorp as many nutrients as possible.
Network of capilaries
Hepatic portal vein -> straight to the liver

Slide 17 - Tekstslide

Deze slide heeft geen instructies

Large intestines
Indigestible waste
water from digested food
1,2 metre long tube
Solid waste is called faeces

Slide 18 - Tekstslide

Deze slide heeft geen instructies

rectum
Faeces are collected in  the rectum
Muscles control elimination
Faeces can be stored for up to three days. 
(sometimes more - constipation)

Slide 19 - Tekstslide

Deze slide heeft geen instructies

Bacteria
Bacteria are needed to break down undigested materials
Bacteria make vitamins like vitamin K and two kinds of vitamin B

Breakdown by bacteria also produces gas

Slide 20 - Tekstslide

Deze slide heeft geen instructies