Biology Science 1

Cardiovascular (Blood)

Cardiovascular system is divided into 2 main parts

1. Heart : 

- Acts as a pump 

- Circulation of blood throughout the body

2. Blood vessels :

- Forms a network of blood flow throughout the body 

Also includes ; 

3. Blood :

- Carries essential substances to cells

- Carries wastes away from cells 

4. The lymphatic system :

- Transport tissue fluid to bloodstream 

- Delivers nutrients from digestive tract into bloodstream 

Blood 

- Connective tissue 

- The body contains 5 Litres of blood

- Colour : Bright red > High in oxygen ; Dark red > Low in oxygen 

- Arterial Blood pH : 7.35 - 7.45 [ slightly alkaline ]

- 2 Contents Components : Fluid portion [ plasma ] ; Formed elements [ cells and cells fragments ]

Plasma

- Slightly thick and straw-coloured fluid ( slightly yellowish )

Contains [ Very Important* ] : ( remember at least 5 )

1. Water

2. Plasma protein 

3. Gases 

4. Nutrients 

5. Mineral salts

6. Waste products 

7. Hormones 

8. Antibodies and antitoxins 

9. Enzymes 

Plasma : 1. Water 

- 90% - 92% of the plasma 

- Functions : Maintenance of all body fluids & Production of secretions 

Plasma : 2. Plasma protein 

- Location : Mostly produced in Liver 

[ Very Important* ] ; ( remember at least 3 ) 

1. Albumin > Keep water in plasma 

2. Fibrinogen > Essential for blood clotting 

3. Heparin > Prevent from abnormal blood clotting ( e.g. Heart Attack )

4. Globulin

5. Prothrombin > Essential for blood clotting 

Plasma : 3. Gases

- Consist of Oxygen, Nitrogen and Carbon Dioxide 

- Oxygen and Nitrogen enters during inhalation 

- Carbon Dioxide is the end product during respiration 

Plasma : 4. Nutrients