B4 Blood related stuff Flashcards
What is the structure of blood plasma?
- Straw yellow liquid
- Made up of water and dissolved substances.
What is the function of blood plasma?
- Plasma transports many dissolved substances around the body.
- Examples include digested foods (e.g. glucose), gases (e.g. carbon dioxide), wastes (e.g. urea) and hormones (e.g. insulin), antibodies, anti-toxins.
- Plasma also transports heat around the body.
What is the structure of red blood cells?
- Very small in size. This provides a large surface area to volume ratio.
- They contain Haemoglobin
- This is a red pigment that binds oxygen –> oxyhaemoglobin.
- They are shaped like discs –(biconcave) but are thicker at the edges.
- They have NO nucleus (so there is more space for haemoglobin)
What is the function of red blood cells?
- To transport oxygen to all the body cells for respiration.
- Haemoglobin binds oxygen molecules forming oxyhaemoglobin.
What is the structure of white blood cells?
- Much bigger than red blood cells.
- Much fewer in number than red blood cells.
- They HAVE a nucleus.
- They have no definite shape
What is the function of white blood cells?
The fight disease in the body.
Name the 2 types of white blood cell and explain how they fight disease.
- Phagocytes – engulf (‘eat’) pathogens.
- Lymphocytes – create antibodies which destroy pathogens.
What is the structure of platelets?
- These are tiny fragments of cells.
- They have NO nucleus.
- They cause blood to clot.
What is the function of platelets?
Their function is to help form blood clots.
This helps seal wounds (and prevent blood loss) when we cut ourselves
What is meant by humans having a ‘double circulatory system’?
The heart is an organ that pumps blood around the body in a double circulatory system.
The right ventricle pumps blood to the lungs where gas exchange takes place.
The left ventricle pumps blood around the rest of the body.
Describe the structure of an artery.
- Thick collagen, elastin & muscle wall.
- Narrow lumen.
Describe the structure of a vein?
- Thin muscle & elasin wall.
- Wide lumen
- Have valves
What is the function of valves in veins?
Valves prevent the back-flow of blood.
What type of blood do arteries (usually) carry?
Oxygenated blood
What type of blood do veins (usually) carry?
Deoxygenated blood
Describe the structure of a capillary.
- Very small blood vessel
- Endothelium wall is just one cell thick
What is the function of capillaries?
Allow fast exchange/diffusion of substances e.g. glucose, oxygen - out of the blood into the body cells/tissues.
Describe the pathway of blood through the heart.
(RHS) Vena cava –> right atrium –> right ventricle –> pulmonary artery (pumps blood to the lungs) –> (LHS) Pulmonary vein –> left atrium –> left ventricle –> aorta (pumps blood all around the body)
What are the 2 top chambers of the heart called?
Left and right atria (singular atrium)
What are the 2 bottom chambers of the heart called?
Left and right ventricles
Which blood vessel carries deoxygenated blood into RHS of the heart?
Vena cava
Which blood vessel carries oxygenated blood into the LHS of the heart?
Pulmonary vein
What are the coronary arteries?
These are the arteries that supply the heart muscle with oxygen and glucose for respiration.
How can blocked coronary arteries lead to heart disease?
In coronary heart disease layers of fatty material build up inside the coronary arteries, narrowing them. This reduces the flow of blood through the coronary arteries, resulting in a lack of oxygen for the heart muscle.
