circulatory system Flashcards
1
Q
what is the circulatory system?
A
the link between cells inside the body which have certain requirements and the environment outside the body
2
Q
what are the functions of blood?
A
transport O2 and nutrients to all cells
- transport CO2 & waste away from cell
- transport hormones
- maintaining Ph of body fluid
- maintain body temp
- protect against disease
3
Q
what is plasma?
A
- 55%
- watery liquid
- transport cells, nutrients, hormones and proteins
4
Q
what are erthrocytes?
A
- 41%
- red blood cells
- bioactive shape
- don’t contain a nucleus
- transport oxygen from lungs to cells
5
Q
what are leucocytes?
A
- 1%
- white blood cells
- fight infection
6
Q
what are the different types of leucocytes?
A
- neutrophils = contains enzymes to digest pathogens
- monocytes = form other cells
- lymphocytes = involved in immune response
- basophils = responsible for allergies, produces heparin and histamine to defence
- eosinophils = inflammatory responses
7
Q
what are thrombocytes?
A
- platelets
- clot blood when needed
8
Q
what occurs during blood clotting?
A
- vasoconstriction: muscles in small artery’s contract
- platelet plug: platelets build up in the affected area to stop blood flow
- coagulation: blood clots to reduce blood flow
9
Q
what are capillaries?
A
- form a network to carry blood to cells in the body
- one cell thick for easy diffusion
- link between arteries and veins
10
Q
what are arteries?
A
- carry blood away from the heart
- thick, muscular walls, elastic
- no valves
11
Q
what are veins?
A
- carry blood towards the heart
- thin, inelastic walls
- often have valves
12
Q
what is the heart?
A
- pump that pushes blood around the body
- enclosed by the pericardium
- left and right separated by the septum
13
Q
how does blood flow through the heart?
A
- enters through the superior vena cava and inferior vena cava
- goes into the right atrium
- then through the tricuspid valve
- it goes through the right ventricle
- into the pulmonary valve
- out through the pulmonary artery
- goes to the lungs where it becomes oxygenated
- returns back through the pulmonary vein
- into the left atrium
- through the mitral valve
- into the left ventricle
- through the aorta where it is pumped to the rest of the body
14
Q
what is the cardiac cycle?
A
- Comprises two separate “circuits” in the body in which blood will travel
- Left and right of the heart function as 2 separate pumps
15
Q
what is diastole?
A
- heart muscle relaxes
