Transporting Materials Unit 3 Flashcards
Why do we need a double circulation system
One carries blood from your heart to your lungs and back. This allows oxygen and carbon dioxide to be exchanged with the air in the lungs.
The other carries blood around the rest of your body and back again to the heart.
A double circulation system like this is vital in warm blooded active animals like humans. It makes our circulatory system very efficient. Fully oxygenated blood returns to the heart from the lungs. This blood can be sent off to different parts of the body at a high pressure. So more areas of the body can receive fully oxygenated blood quickly
Function of coronary arteries.
Supplies the heart muscle with oxygen and glucose
Describe how the heart works. And how it’s adapted for pumping blood around the body.
The structure of the human heart is adapted for pumping blood to your lungs and your body. The two sides of the heart fill and empty at the same time. This gives a strong coordinated heart beat.
Blood enters the top chambers of your heart (the atria). The blood coming into the right atrium from the vena cava is deoxygenated blood from your body.
The blood coming into the left atrium in the pulmonary vein is oxygenated blood from the lungs.
The atria contract together and force blood down into the ventricles. Valves close to stop the blood flowing backwards out of he heart.
- the ventricles contract and force blood out of the heart
- the right ventricle forces deoxygenated blood to the lungs in the pulmonary artery.
- the left ventricle pumps oxygenated blood around the body in a big artery called the Aorta.
As the blood is pumped into these two big vessels valves close to make sure the blood flows in the right direction.
Function of heart valves.
Ensuring blood flows in the right direction stopping blood flowing backwards out of the heart.
How are capillaries adapted to their function
Capillaries form a huge network of tiny blood vessels linking the arteries and the veins. Capillaries are narrow with very thin walls (1 cell thick) this enables substances such as glucose and oxygen to diffuse easily out of your and into the cells.
Similarly the substances produced by your cells such as carbon dioxide pass into the blood through the walls of your capillaries.
What is the function of the blood circulation system
Supplying Oxygen and Glucose , Water, Ions to cells and removing waste products that they produce.
What is carried in blood plasma
Plasma carries.
1) red blood cells
2) white blood cells
3) platelets
4) many dissolved substances
5) urea is carried to your kidneys in plasma
6) Carbon dioxide produced in the organs of your body is carried back to the lungs in plasma.
How are red blood cells adapted to their function
They are biconcave discs, this gives them an increased surface area to volume ratio, over which the diffusion of oxygen can take place.
They are packed full of a special red pigment called haemoglobin that carries oxygen
They don’t have a nucleus this allows for more space to carry haemoglobin molecules.
What is oxygenated haemoglobin called
Oxyhaemoglobin
