Pages in this set

Page 1

Preview of page 1
Closed circulatory system:
Blood leaves the heart under high pressure and flows along arteries and then
arterioles to capillaries.
Capillaries come in large numbers and they exchange substances between blood and
cells.
After passing through capillaries, blood goes back to the heart via venules and then
veins.
Valves in veins…

Page 2

Preview of page 2
Atrial systole:
Blood under lower pressure flows along pulmonary veins and vena cava.
As atria fills with blood, pressure against the atrioventricular valves cause them to
open, leaking blood into the ventricles.
As atria walls contract more blood is forced into the ventricles.
Ventricular systole:
Ventricles contracts base upwards increasing…

Page 3

Preview of page 3
The enzymes thrombin catalyses the conversion of fibrinogen in to fibrin.
The long fibrin strands forms a mesh and traps blood cells to form a clot.

Large-scale studies:
Cohort study:
A group of people are followed over time to see who develops the disease.
Case control study:
A group of…

Page 4

Preview of page 4
Lipids:
The most common lipids we eat are triglycerides
Used as energy stores in plants and animals
They are made up of three fatty acid and one glycerol molecule
These are linked together by condensation reactions
The bond that forms between them is an ester bond
Three ester bonds are…

Page 5

Preview of page 5
A high salt intake cans cause kidneys to retain water. This also increase blood
pressure
Stress:
In stressful situations the release of adrenaline causes arteries and arterioles to
constrict resulting in raised blood pressure.
Alcohol:
Heavy drinking raises blood pressure, irregular heartbeat and obesity.


Reducing the risk of CVD:
Taking…

Comments

No comments have yet been made

Similar Biology resources:

See all Biology resources »