1. The cardiovascular system, diabetes and obesity

2. Overview
This topic looks at the structure and function of the cardiovascular system with an emphasis on diabetes, obesity and their effects on the system.
There are 4 areas of study
The structure and function of arteries, capillaries and veins
The structure and function of the heart
The pathology of cardiovascular disease
Blood glucose levels and obesity

3. The structure and function of arteries, capillaries and veins
What do you know already?
Label the diagrams provided and write any notes
What you need to know?
Structure of all 3 types of blood vessel
Flow of blood in the vessels including pressure changes
The exchange of materials between blood vessels and tissues
How the lymph system works with the circulation

4. Overview

5. Overview

6. Overview Heart pumps blood 2 circulations (lungs/body) Arteries
Capillaries
Veins
Blood variety of reds
Diagrams Oxygenated blood (red)
Diagrams Deoxygenated blood (blue)
Diagrams arteries red except pulmonary artery
Diagrams veins blue except pulmonary vein
Arteries blood away from heart
Veins blood towards the heart
Arteries>arterioles>capillaries>venules>veins
Pressure changes from high to low

7. Arteries

8. Arteries Outer layer of connective tissue with elastic fibres
Middle layer with smooth muscle and elastic fibres
Inner lining is the endothelium
Lumen (channel) is relatively narrow
Elastic walls stretch and recoil with surge of blood
Smooth circular muscle can contract (vasoconstriction)
Smooth circular muscle can relax (vasodilation)
Blood flow can be controlled
Pressure higher than capillaries and veins

9. Capillaries Link arteries to vein
Allow exchange of substances with tissues
Endothelium 1 cell thick
Close to all cells
O2, dissolved food, ions
CO2, metabolic waste

10. Tissue fluid Fluid is squeezed out of the blood from capillaries
Difference in pressure between capillary and tissue cells causes fluid to leave capillaries (plasma)
Tissue fluid contains glucose, amino acids, respiratory gases and ions
Tissue fluid contains very little or no protein, it is too big to be passed out of the capillaries

11. Veins

12. Veins Outer layer of connective tissue with elastic fibres
Middle layer with smooth muscle
Elastic fibres and muscle wall much thinner than arteries
Not very elastic
Wider lumen (channel) than arteries
Lower pressure than arteries
Valves prevent backflow of blood
Surrounding muscle tissue helps move blood by contractions
Pressure lower than capillaries and arteries

13. Lymphatic system and circulation
Some excess fluid enters the lymphatic vessels
Lymph fluid is moved by muscles compressing lymph vessels
Lymph fluid is returned to veins in the arms via lymphatic ducts

14. What do you know? What are the 3 types of blood vessel?
Describe them (diagram and label)
Describe their function and relate to structure
Describe and explain pressure changes in system
What is vasoconstriction?
What is vasodilation?
Why do veins have valves?
What is tissue fluid?
What is lymph?
What does the lymphatic system do?