What are the 4 advantages of using a single blood component rather than whole blood?
- More patients can be treated from each single pint of donated blood
- The dose of the blood component can be change so that it is optimal for each specific patient
- It is more cost effective
- The process is more efficient
- There is an abundant supply
- There is no risk of rejection
- There is no risk of infection e.g. HIV
- It has a longer shelf-life than whole blood
Why are scientists trying to develop artificial blood products?
Whole blood has a short shelf-life i.e. it can't be stored for very long
Why does the left ventricle have the thickest wall of all the 4 chambers in the heart?
The LV has to contract to generate the largest force to move the blood from the LV to all over the body i.e. they have to move the blood over the largest distance and overcome the greatest resistance (friction)
What is the purpose/function of the valves inside veins?
To prevent the back flow of blood and ensure blood only flows in one direction
The valves also prevent blood from pooling (collecting) in the lower limbs
What is the role/function of the plasma?
It is the liquid component of the blood that the cells are suspended in and chemicals are carried in
How are the lungs adapted for gaseous exchange?
They have many alveoli
The alveoli have walls which are one cell thick
The alveoli are covered in a rich blood supply (many capillaries)
The lining of the alveoli is moist (to dissolve the gases)
Give 2 advantages of biological heart valves
No medication needs to be taken
They are fully effective
Which type of blood vessels have tiny gaps (pores) in their walls?
What are the 3 different roles/functions of white blood cells?
To produce antibodies
To produce antitoxins
To carry out phagocytosis (engulf bacteria or toxins and break them down into harmless products)
What is a double circulatory system?
A system where the blood passes through the heart twice per full circuit around the body.
What is the function of the left ventricle?
Receives oxygenated blood from the left atrium
Contracts to generate a high force to move the oxygenated blood to the rest of the body via the aorta
The left ventricle pumps oxygenated blood around the rest of the body.
Give 2 SOCIAL arguments for the development of artificial hearts
- Gains time for the patient
- No waiting time
Why does the right ventricle have thicker walls than the atria?
The RV has to contract to generate a larger force to move the blood from the RV to the lungs i.e. they have to move the blood over a larger distance and overcome a larger resistance (friction)
Give 2 disadvantages of biological heart valves
They usually need replacing after 15 years
There are ethical issues for some people e.g. is it right to use tissue from animals
Describe the chemical reaction that happens in the red blood cell in the lungs
haemoglobin binds with oxygen to form oxyhaemoglobin haemoglobin + oxygen = oxyhaemoglobin
What is the role/function of the pulmonary artery?
Carries deoxygenated blood away from the heart to the lungs
The blood has low oxygen and high carbon dioxide
How do cells become specialised?
The cells differentiate
This means they change in different ways:-
- they change their shape e.g. sperm cell becomes streamlined and develops a flagellum (tail)
- they change their cell contents e.g. produce specific proteins e.g. haemogobin in a RBC, mucus in a goblet cell
- they change the number of certain cell organelles to become suited for a specific function e.g. pallisade mesophyll cells increase thier number fo chloroplasts
What are blood components?
These are parts of blood that have been separated from donated blood e.g. red blood cells platelets plasma
What is the function of glandular tissue?
To produce and secrete chemicals such as enzymes and hormones
What happens to the heart valve when it becomes faulty?
The valve may not open fully (as they can become stiff)
The valve may develop a leak (which then allows blood to flow in both directions)
What are the 4 main components of blood?
Red blood cells
White blood cells
Define the term 'organ system'
A group of organs working together to carry out specific functions
What is the function of the vena cava?
Carries deoxygenated blood from the rest of the body back to the right atrium
The blood has low oxygen and high carbon dioxide
What are the 3 negatives/disadvantages of having a stent fitted?
There can be complications during surgery e.g. having a heart attack, reacting to the anaesthetic
There is a risk of a blood clot forming near the stent - this is called a thrombosis
If a thrombosis forms there is a risk of a stroke or heart attack or pulmonary embolism
What are blood products?
They are components (parts) of blood that are obtained from donated blood e.g. red blood cells, plasma, platelets
How does coronary heart disease occur? Hint: 5 steps
Layers of fatty material build up INSIDE the coronary artery wall
This narrows the lumen of the coronary artery
This reduces the blood flow through the coronary srtery
This reduces the amount of oxygen & glucose delivered to the cardiac muscle cells that make up the heart walls
This can cause a heart attack
Give an example of a cardiovascular disease
Coronary heart disease
Myocardial infarction (heart attack)
What is the importance of blood clotting? Hint: 3 purposes
To seal and close a wound
To prevent blood loss
To prevent the entry of micro-organisms
Which type of blood vessels have smooth muscle and elastic fibres in their walls?
ONLY arteries and veins
Different blood components have different uses. What is the use of platelets?
To treat or prevent bleeding in patients with a low platelet count