Flashcards in The Blood And Blood Vessels - Part 2 (T2) Deck (19):
What are the three types of blood vessels in the human body?
What is the function of the arteries?
To pump blood away from the heart.
What three main characteristics do arteries have to ensure they can do their job?
- they need to be TOUGH and elastic so they do not burst.
- they are THICK and have a small lumen down the centre.
- they possess a TOUGH OUTER LAYER and an ELASTIC INNER LAYER to cope with the stretching and contracting caused by the high pressure pulses of blood.
How does the elastic inner layer of the arteries help to keep the blood flowing?
The elastic layer is made up of elastic fibres and smooth muscle which contracts, helping to keep the blood flowing.
What is the name of the third layer that lines the lumen in the arteries?
What is the endothelium made up of and how does it help keep the blood flowing?
It is made up of endothelial lining cells, giving a smooth surface to the lumen, helping to keep the blood flowing.
What is the function of the veins?
To carry blood back to the heart.
Why don't veins need to be as strong as the arteries?
Blood returning to the heart is at a much lower pressure to blood leaving the heart.
What similar structure do veins and arteries share?
They both have a similar cross-sectional structure.
What are the main differences between veins and arteries?
- veins have a much wider lumen and thinner walls
- veins have valves, arteries do not
Why do veins have valves and where are they?
Valves occur occasionally along the length of the veins, ensuring blood can only travel in one direction.
What is the function of the capillaries?
To carry blood close to all the tissues and organs.
What are the capillaries made of?
Capillaries are made of a single layer of endothelial cells around a very small lumen.
How does the structure of the capillaries help make them do their job?
- the one cell thickness of capillaries allows molecules to move in and out of them by diffusion.
- nutrients can be taken to every cell in the body and waste products like carbon dioxide can be removed.
What makes up the circulatory system?
- the heart
How does blood go to and from the liver?
- to the liver by the hepatic artery
- from the liver via the hepatic vein
How does blood travel to and from the kidneys?
- to the kidney via the renal artery
- from the kidney via the renal vein
How does blood travel to and from the lungs?
- to the lungs via the pulmonary artery
- from the lungs via the pulmonary vein