• Improve Tuition
  • Improve Tuition
  • Improve Tuition
  • Improve Tuition
  • Improve Tuition

Blood vessels

Fill in your details and we
will get back to you shortly

 Book a trial session enquiry

 

Science


Blood vessels


There are three types of blood vessels, which have different functions:

 

⇒   Arteries – they carry blood away from the heart and usually

     carry oxygenated blood ( except from the pulmonary artery)

⇒   Veins – they carry blood to the heart and usually carry

     oxygenated blood (except from the pulmonary vein)

⇒   Capillaries – they are involved in the exchange process between

     cells

 

 

Arteries


When the heart pumps blood out, is leaves the heart at very high pressure,

therefore to withstand this pressure the walls of the arteries are very elastic

to ensure they can expand and deal with the extreme pressure without

bursting.

 

The walls are made of thick muscle and elastic fibers which allows it to recoil

back into position and help maintain that  pressure around the body.

 

Veins


Veins take blood back to the heart, because after the blood has traveled

around the body, it looses the pressure it gained from the initial contraction.

Therefore the walls of the veins do not have to have thick walls as it does

not need to deal with the pressure.

 

The veins do have a unique mechanism, which allows the blood to flow in the

right direction. The veins have valves to make the sure the blood travels

towards the heart.

 

Capillaries


Arteries branch into capillaries, which then divide into even more capillaries.

The capillaries are really close to the cells and are extremely thin. They also

have a very high total surface area.

 

All these aspects help to increase the diffusion rate into the cells.

Related Topics


Classification                             The Heart

Inside the heart                         Blood