(3.2) Circulatory Systems Flashcards
Why do we need transport systems?
- Size
- SA:V
- Level of metabolic activity
What are the common features of a circulatory systems?
- Fluid
- Pump
- Exchange surfaces
What is the role of fluid in circulatory systems?
To transport dissolved nutrients
What is an example of an organism that has an open circulatory system?
Insects
What is an example of an organism that has a closed circlulatory system?
Fish
What is a closed circulatory system?
When the fluid is trapped in vessels
What is an open circulatory system?
The fluid is not enclosed in vessels
What are the disadvantages of an open circulatory system?
- Less efficient
- Low blood pressure
- Can’t direct the flow of fluid and it is rather affected by body movement
What are the disadvantages of an open circulatory system?
- Less efficient
- Low blood pressure
- Can’t direct the flow of fluid and it is rather affected by body movement
What is a single circulatory system?
Where the fluid only enters the pump once per circuit
What is an example of an organism with a single circulatory system?
Fish
What is an example of an organism with a double circulatory system?
Mammals
What are the disadvantages of a single circulatory system?
The blood pressure decreases as the blood gets further away from the heart
What is peristalis?
The way in which the fluid within an insect’s circulatory system moves - in waves as the pump contracts
What fluid is within the circulatory system of an insect?
haemolymph
What are the two parts of a mammilian circulatory system?
- Systemic circulation
- Pulmonary circulation
Why are there two circulatory systems within the mammilian body?
- they have a high metabolic rate
- to change blood pressure
What happens if blood pressure is too high when entering the lungs?
If the blood pressure is too high, the lungs will be damaged. This is because the capillaries start to leak fluid into the alveolus space and they can no longer carry out gaseous exchange. This is called pulmonary adema.
What is the flow of blood within a humans circulatory system?
- deoxygenated blood is pumped into the lungs
- oxygenated blood enters back into the heart
- the oxygenated blood leaves the heart and enters the systemic circulation
- the blood travels past the tissues and oxygenates then
- the deoxygenated blood then returns to the heart
What are the advantages of a double circulatory system?
- blood pressure in lungs is not too high to damage them
- heart can boost pressure before it travels around the body
- body circulations are at a high pressure
What are the materials within the Arteries and Veins?
- lumen
- endothelium
- elastic fibres
- smooth muscle
- collagen fibres
What is the lumen like in an artery and why?
Narrow to maintain a high blood pressure
What is the role of an artery?
Carry blood away from the heart
What is the role of a vein?
Carry blood towards the heart
What is the role of a capillary?
Site of exchange and how tissue fluid is produced
What is the structure of the endothelium and why in the arteries and veins?
- flattened
- smooth - blood flow has minimum resistance due to friction
What is the role of the elastic fibres in an artery?
To allow flexibility of the vessel as it can stretch and recoil when a wave of blood is pushed through