1. Multicellular Organisms Key Area 7 Absorption of materials

2. Materials absorbed in the blood
Learning Intention: Describe what materials must be absorbed in the blood.
Success Criteria: state what materials are carried in the blood and why.
State that tissues contain capillary networks to allow the exchange of materials at a cellular level.

3. Skills for life, learning and work: Understanding new scientific terms
Literacy, Numeracy, HWB:
I can make notes and organise them to develop my thinking, help retain and recall information, explore issues and create new texts, using my own words as appropriate.
LIT 3-15a / LIT 4-15a
Skills for life, learning and work:
Understanding new scientific terms
Becoming confident in new biological terms
Applying new scientific knowledge to make connections and solve problems

4. Starter activity Think:
On a show me board write what the function of the blood is and what materials are carried in the bloodstream.

5. Why does the blood need to carry oxygen and nutrients
Why does the blood need to carry oxygen and nutrients? (think back to the Cell Biology unit!)
Oxygen and nutrients from food must be absorbed into the bloodstream to be delivered to cells for respiration.
Waste materials, such as carbon dioxide, must be removed from cells into the blood stream.

6. All tissues contain capillary networks to allow the exchange of materials at a cellular level.

7. Absorption surfaces
All surfaces involved in the absorption of materials have certain features in common:
Large surface area
Thin walls
Extensive blood supply
These structures include the villi in the small intestine and the alveoli in the lungs.
These increase the efficiency of absorption.
(we will go into detail about the villi and alveoli at a later date).

8. Materials absorbed in the blood
Learning Intention: Describe what materials must be absorbed in the blood.
Success Criteria: state what materials are carried in the blood and why.
State that tissues contain capillary networks to allow the exchange of materials at a cellular level.

9. The Lungs
Learning Intention: To identify the structures and functions of the respiratory system.
Success Criteria: state that the lungs are exchange organs that consist of a large number of alveoli providing a large surface area.
State that oxygen and carbon dioxide are absorbed through the alveolar walls to or from the many blood capillaries.

10. Starter questions
What substances have to be carried to cells by the blood? Which substance has to be carried away from cells?
What features do absorption surfaces have?

11. Respiratory system The lungs are gas exchange organs.
They consist of a large number of alveoli producing a large surface area.
Twig - Lungs : Twig

12. The Lungs
The Lungs

13. Lung Dissection
Bristol Science Centre

14. Alveoli
Oxygen and carbon dioxide are absorbed through the thin alveolar walls to or from the many blood capillaries.
Twig - Alveoli

15. Alveoli
Alveoli

16. Examples of absorption surfaces: alveoli in the lungs
Large surface area
Thin walls
Extensive blood supply
Large number of them to provide a large surface area.

17. Exit task Where does gas exchange takes place in the lungs?
Describe how the alveoli are adapted for gas exchange.

18. The Lungs
Learning Intention: To identify the structures and functions of the respiratory system.
Success Criteria: state that the lungs are exchange organs that consist of a large number of alveoli providing a large surface area.
State that oxygen and carbon dioxide are absorbed through the alveolar walls to or from the many blood capillaries.

19. The Digestive System- the Small Intestine
Learning Intention: to describe how nutrients are absorbed in the small intestine.
Success Criteria: Label a diagram of the digestive system.
State that nutrients from food are absorbed into the villi in the small intestine.
State that the large number of thin walled villi provides a large surface area.
State that each villus contains a network of capillaries to absorb glucose and amino acids and a lacteal to absorb fatty acids and glycerol.

20. Skills for life, learning and work: Understanding new scientific terms
Literacy, Numeracy, HWB:
 I can make notes and organise them to develop my thinking, help retain and recall information, explore issues and create new texts, using my own words as appropriate.
LIT 3-15a / LIT 4-15a
Skills for life, learning and work:
Understanding new scientific terms
Becoming confident in new biological terms

21. The Digestive System
The function of the digestive system is to break down large molecules of food into smaller molecules of food.
This is so it can be absorbed into the bloodstream.
It is absorbed in the small intestine.
Twig - Introduction to Digestion : Twig

22. Label cut out

23. Small intestine
The small intestine is the site of absorption of digested food.
It has various adaptations that make it efficient at doing this.
The small intestine is very long(5-8m) and contains many villi which increases the surface area for absorption to take place.
Villi are finger-like projections lining the small intestine.
Twig - Absorption

24. A Villus
Nutrients from food are absorbed into the villi in the small intestine.
There are millions of villi in the small intestine.
Draw out and label a villus- Highlight the adaptations for absorption

25. Digested food that is absorbed. What are these digested from?
The villi
Part of villus
Digested food that is absorbed.
What are these digested from?
Blood capillary
Glucose and amino acids
Starch and proteins
Lacteal
Glycerol and fatty acids
Fats

26. Examples of absorption surfaces: villi in the small intestine
Large surface area
Thin walls
Extensive blood supply
Large number of them to provide a large surface area.
lacteal
Blood capillary

27. The Digestive System- the Small Intestine
Learning Intention: to describe how nutrients are absorbed in the small intestine.
Success Criteria: label a diagram of the digestive system.
State that nutrients from food are absorbed into the villi in the small intestine.
State that the large number of thin walled villi provides a large surface area.
State that each villus contains a network of capillaries to absorb glucose and amino acids and a lacteal to absorb fatty acids and glycerol.

28. N5 Multicellular Organisms Key area 7 Absorption of materials
Past Paper Practice
National 5
N5 Multicellular Organisms
Key area 7 Absorption of materials

29. 1

30. 2

31. 3

32. 4

33. 5

34. 6

35. 7

36. 8

37. 9

38. 1

39. 2

40. 3
(A villus has) a thin wall/a large surface area/a good blood supply/many capillaries (any 2)
There are a large number of villi - So this also increases surface area/creates a large surface area OR makes absorption/ diffusion fast(er)/more (1 mark)

41. 4
Alveoli

42. 5 Large surface area Thin walls/walls are one cell thick
Good/rich blood supply/dense capillary network
Moist

43. 6

44. 7

45. 8
11:7
Oxygen/nutrients/glucose/amino acids

46. 9
(Large) surface area /(rich) blood supply/ (dense) capillary network