Paper 1: Topic 2 Organisation - Heart, blood vessels & blood (IV form) Flashcards
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?
Only capillaries
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?
Plasma
Red blood cells
White blood cells
Platelets
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
Angina
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
What is the function of the circulatory system?
To deliver oxygen and nutrients to all cells and remove all waste products from cells in a multi-cellular animal
Describe the structure of a red blood cell
Hint: Think of 3 facts
Biconcave shape
No nucleus (or mitochondria)
Contains a specialised protein called haemoglobin
Give 4 SCIENTIFIC arguments for the development of artificial hearts
Compensates for a shortage of biological donor hearts
Less likely to be rejected (as the metal and plastic is not recognised as foreign by the person’s immune system)
No need to tissue match
No need for immuno-suppressants to be taken by the patient for the rest of their life
What is the name of the main vein in the human body?
Vena cava
Why have scientists developed artificial hearts?
There is a shortage of donor hearts in the UK
They extend a patient’s life (until a donor heart is found)
They can be used to allow the patient’s own heart to rest and aid recovery
What is the role/function of the capillaries?
To allow the exchange of nutrients (e.g. glucose and oxygen) from the plasma to the cells
To allow the removal of waste products e.g. carbon dioxide and urea from cells into the blood plasma
What is the name of the main artery in the human body?
Aorta
Describe the chemical reaction that happens inside a red blood cell in the tissues
oxyhaemoglobin breaks down into haemoglobin and oxygen oxyhaemoglobin = oxygen + haemoglobin
What are the 5 key features of any blood substitute?
They must not cause rejection
They must have a long shelf-life
They must be easy to store and transport
They must not transmit infections
They must be good are transporting oxygen
List the organs that make up the digestive system
Glands = pancreas & salivary glands
Stomach
Small intestine
Liver
Large intestine
What are the consequences (signs and symptoms) of a faulty heart valve?
A person becomes breathless easily (as they have low oxygen supply)
The person can die (as a result of insufficient oxygen)
How do you calculate a person’s breathing rate?
Breaths per minute = number of breaths in a specified amount of time (number of minutes) divided by the number of minutes
Give 7 SCIENTIFIC arguments against the development of artificial hearts
Patients usually have to take anticoagulants to thin the blood and reduce the risk of clots
The device may wear out or the electric motor may fail
Surgery to fit an artificial heart can lead to bleeding & possible infection
There can be problems with the size of the artificial heart
Usually it is not a long term solution i.e. not a cure just a temporary solution
Surgery can result in bleeding and infection
Blood flow is not smooth and this can result in problems with blood clotting causing other medical problems e.g. stroke
What is the role/function of the ribcage?
To protect the heart and lungs
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 veins?
To carry deoxygenated blood towards the heart at low blood pressure
REMEMBER: the pulmonary vein is different as it carries oxygenated blood towards from the lungs to the heart
What are the 4 risks in ANY type of valve replacement?
Risks of infection (during and after surgery)
Risks of reaction to the anaesthetic during surgery
Possible clots forming leading to blocked blood vessels
Clots can result in a heart attack or stroke
What is an artificial heart?
A mechanical device that is used to treat a person whose own heart has failed
Remember: The mechanical heart only supplies the heart valves. It doesn’t generate a force. The force is generated by an external power pack.
What are the advantages of replacing a faulty heart valve? Hint 1: applies to BOTH biological and mechanical heart valves Hint 2: 5 steps
The new valve improves the circulation of blood
So more oxygen is delivered to the tissues
So more cell respiration can occur
So more energy is releases
And hence the person can lead a more active life again
What is the role/function of the arteries?
To carry oxygenated blood away from the heart at high blood pressure
REMEMBER: the pulmonary artery is different as it carries deoxygenated blood away from the heart to the lungs
What are the 3 disadvantages of taking statins?
They have to be taken long-term and regularly
They can cause side effects e.g. headaches, kidney failure, liver damage, memory loss
Their effect is not immediate - the person has to take them for some time before any benefit is observed
Define the term ‘cell’
The simplest building block of all living organisms
Describe the shape of a typical white blood cell Hint: think of 3 facts
Larger cells (larger than RBC and platelets)
May contain a large kidney bean shaped nucleus or may contain a lobed nucleus
What is the function of the left atrium?
Receives oxygenated blood from the lungs
Contracts to generate a small force to move the oxygenated blood to the left ventricle through the atrio-ventricular valves (bicuspid valve)
Define the term ‘cardiovascular disease’
Disease that affect the heart or the blood vessels
Give 4 disadvantages of mechanical (man-made) valves
They require the person to take anti-coagulants for the rest of their life
There is an increased risk of a blood clot forming
Open heart surgery is required to insert the mechanical valave
They can’t be used for everyone e.g. if a person is still growing
Which type of blood vessel has a pulse?
Only the arteries
What are the 4 risks in ANY type of valve replacement?
Risks of infection (during and after surgery)
Risks of reaction to the anaesthetic during surgery
Possible clots forming leading to blocked blood vessels
Clots can result in a heart attack or stroke
How do you calculate the rate of blood flow?
rate of blood flow = volume of blood passed through a blood vessel divided by the number of minutes
Which type of blood vessels have walls which are only one cell thick?
Only capillaries
Describe the pulmonary circuit
The right ventricle of the heart pumps deoxygenated blood to the lungs and then the oxygenated blood returns to the left atrium of the heart i.e. heart to lungs to heart
How does a stent work?
It pushes the artery wall open to restore blood flow and allow oxygen and glucose to be delivered to the cells
Give 4 advantages of mechanical (man-made) valves
Last a ling time ~20-30 years
Very effective
No need to replace the valve i.e. permanent fix
There are no ethical issues
What can happen if a person lacks sufficient platelets?
Bruising and excessive blood loss
Why may a person need a blood transfusion?
After an accident which has caused SEVERE blood loss
What is the function of the right atrium?
Receives deoxygenated blood from the rest of the body
Contracts to generate a small force to move the deoxygenated blood to the right ventricle through the atrio-ventricular valves (tricuspid valve)
How can coronary heart disease be treated?
Hint: 2 methods
Stents
Statins
What are the two types of valves found in the heart?
Semi-lunar valves
Atrio-ventricular valves
Describe the systemic circuit
The left ventricle of the heart pumps oxygenated blood to all the parts of the body (except the lungs) and then the deoxygenated blood returns to the right atrium of the heart i.e. heart to body to heart
What is the role of the diaphragm during ventilation?
The diaphragm contracts during inhalation so that the diaphragm flattens causing the volume of the thorax to increase
The diaphragm relaxes during exhalation so that the diaphragm becomes dome shaped causing the volume of the thorax to decrease
Why do the artery walls contain elastic fibres?
The elastic fibres stretch and recoil when blood surges through them
Why do arteries walls contain muscle fibres?
The muscle fibres can help move the blood through the blood vessel
What is the function of the right ventricle?
The right ventricle pumps deoxygenated blood to the lungs where gas exchange takes place
Receives deoxygenated blood from the right atrium
Contracts to generate a low force to move the deoxygenated blood to the lungs via the pulmonary artery
Why is it important to maintain a patient’s blood volume?
To enable the heart to continue to contract to move the blood around the body
This ensure oxygen and glucose are still delivered to all respiring cells and also removes any waste products from cells
What is the role/function of platelets?
They help the blood to clot by helping to produce a mesh that covers the open wound
Platelets get trapped in the mesh and form a clot that seals the wound
What are atrio-ventricular valves?
Valves which are located between the atrium and the ventricle
What is the function of the pulmonary vein?
Carries oxygenated blood from the lungs to the left atrium
The blood has high oxygen and low carbon dioxide
What is artificial blood?
A blood substitute e.g. a salt solution
Give 3 possible causes of a faulty heart valve
Old age
Heart attack
Infection
What features must any blood substitute have?
It must not cause rejection
It must have a long shelf-life
It must be easy to transport and store
It must not transmit any infections
It must be good at transporting oxygen
How can faulty heart valves be treated?
Replace the valve with either a biological heart valve or a mechanical valve
What is the function of the aorta?
Carries oxygenated blood at high pressure to the arteries of the circulatory system
The blood has high oxygen and low carbon dioxide
What are the key structures in the thorax?
Rib cage
Heart
Lungs
Diaphragm
What is the role/function of red blood cells?
Oxygen diffuses into the red blood cell and combines with haemoglobin to form oxyhaemoglobin
Hence red blood cells transport oxygen around the body
What are semi-lunar valves?
Valves which are located between the ventricle and the blood vessel leaving the heart
Give 3 SOCIAL arguments against the development of artificial hearts
- It is not natural
- Inconvenience of having to carry a battery pack all the time
- May have to remain in hospital therefore lifestyle is affected long term (possible loss of job etc)
What is the role of the bronchioles?
To carry air from the bronchi to the alveoli
What is the main component of plasma?
Water
What is the role/function of the trachea?
To carry air from the mouth to the bronchi
What are platelets?
Fragments of cells that have no nucleus
What are the names of the four chamber of the heart?
Right atrium
Right ventricle
Left atrium
Left ventricle
How to statins work? Hint: think of 2 facts
They reduce blood cholesterol levels
This reduces the rate at which the fatty materials are deposited in the artery walls
What is the difference between biological and mechanical valves?
Biological valves: usually taken from other humans or animals such as pigs and cattle
Mechanical valves: made of titanium and polymers i.e. man-made
What is the function of epithelial tissue?
To cover the inside and outside of certain organs e.g. stomach
Which type of blood vessels have valves inside them?
Only veins
What is the function of the semi-lunar valves?
To prevent the back flow of blood from the blood vessel leaving the heart back into the ventricle
Define the term ‘tissue’
A collection of similar cells that work together to carry out a specific function
What is the function of the atrio-ventricular valve?
To prevent the back flow of blood from the ventricle back into the atrium
How to statins reduce blood cholesterol levels?
They reduce the LDLs in the blood and they increase the HDLs in the blood
What is a stent?
A metal mesh that can be inserted into an artery to keep the artery lumen open
What are the 4 advantages of taking statins?
They reduce the amount of LDLs in the blood
They reduce the risk of strokes, heart attacks and coronary heart disease
They increase the amount of HDLs in the blood
There is some evidence that they also help prevent some other diseases
Why are the alveoli covered in a large network of capillaries?
To allow efficient gas exchange by maintaining a rich blood supply to maintain the concentration gradient
Different blood components have different uses. What is the use of fresh, frozen plasma?
To treat patients who have suffered excessive blood loss
What is the role/function of the bronchi?
To carry air from the trachea to the bronchioles
What is the function of muscular tissue?
To contract to bring about movement of what the muscle is attached to
What are the 6 positives/advantages of having a stent fitted?
- They are very effective
- Surgery is quick
- Surgery is less invasive as it can be fitted using a cather (and not open heart surgery)
- Only a local anaesthetic is required
- The risks from the surgery are reduced (as the procedure is less invasive)
- Recovery time is short
What are the names of the two circuits in the double circulatory system in humans?
Pulmonary circuit and systemic circuit
What are the 3 types of blood vessel?
Arteries, veins and capillaries
Different blood components have different uses. What is the use of packed red blood cells?
To restore the oxygen carrying capacity in a patient who has anaemia or has suffered excessive blood loss
Describe the size (width) of the lumen of the 3 different blood vessels. In each case explain why this is important.
Arteries = narrow lumen (to maintain high blood pressure)
Veins = wide lumen (to reduce resistance to blood flow and maintain blood pressure)
Capillaries = width of the lumen is the same as the width of a red blood cell (to reduce the diffusion distance for oxygen)
Give 3 SOCIAL arguments against the development of artificial hearts
It is not natural
Inconvenience of having to carry a battery pack all the time
May have to remain in hospital therefore lifestyle is affected long term (possible loss of job etc)
How effective are stents?
They are effective in keeping a person alive for a long time
What is the function of the coronary arteries?
Deliver oxygen and nutrients to the cardiac muscle cells that make up the heart walls
Why is it important that any blood or blood substitute is transferred without any bubbles?
The bubbles would enter the bloodstream and could cause a heart attack or stroke or respiratory failure
Define the term ‘organ’
A group of tissues working together to carry out specific function(s)
What are HDLs?
They carry fat AWAY from the artery wall and DECREASE the amount of fat that is deposited in the artery wall
Hint- Think: “H” = healthy
What tissue is the heart made up from?
Cardiac muscle
What are LDLs?
They carry fat TO the artery wall and INCREASE the amount of fat that is deposited in the artery wall
Hint -Think: “L” = lethal
What are the 3 components (parts) of the circulatory system?
Heart
Blood vessels (arteries, capillaries and veins)
Blood
Give 7 different chemicals are found in plasma?
Glucose
Amino acids
Urea
Hormones
Proteins
Antibodies
Antitoxins
Place these chambers of the heart in order of the thickness of their wall (start with the thinnest wall) Right atrium Left ventricle Right ventricle Left atrium
Right and left atria (thinnest)
Right ventricle (thicker)
Left ventricle (thickest)
Why must faulty heart valves be replaced, for example if they become stiif or hardened as the person ages?
- The faulty valve will reduce the amount of oxygenated blood leaving the heart
- This means the heartwill have to beat faster so that it can supply sufficient oxygen to the cells
State 3 structural differences between an artery and a vein
Remember the Q is about structural differencs so you can’t discuss the functions of the blood vessels
- Artey lumen is narrow, lumen of vein is wide
- Arteries do not have valves, veins do have one-way valves
- Artery has thick muscular wall, vein has thin muscle layer in its wall
State 2 structural differences between an artery and a capillary
Remember the Q is about structural differencs so you can’t discuss the functions of the blood vessels
- Artey lumen is narrow, lumen of capillary is very narrow (only the same as a single red blood cell)
- Artery has thick muscular wall, capillary wall is only one cell thick
State 2 structural differences between a vein and a capillary
Remember the Q is about structural differencs so you can’t discuss the functions of the blood vessels
- Vein lumen is wide, lumen of capillary is very narrow (only the same as a single red blood cell)
- Vein has muscular wall, capillary wall is only one cell thick
Compare the composition (contents) of the blood in an artery and the blood in a vein
- Blood in an artery has high levels of oxygen, a vein has low levels
- Blood in an artery has high levels of glucose, a vein has low levels
- Blood in an artery has low levels of carbon dioxide, a vein has high levels
- Blood in an artery has low levels of lactic acid, a vein has high levels
State 4 advantages of using artifical blood for a transfusion
- No risk of rejection
- There is an abundant supply
- There is a lower risk of infection e.g. no risk of HIV
- It has a longer shelf-life than human blood
Name the blood vessel that supplies the cardiac (heart) muscle with oxygen and glucose
Coronary artery
Describe what happens if the coronary artery becomes blocked (2)
The person may have a heart attack
As the cardiac muscle no longer recieves oxygen and glucose and so the heart tissue dies
Describe the structure and function of red blood cells
Structure:
- Biconcave cells
- Appear smaller than white blood cells when observed under a light microscope
- Have no nucleus
Function:
- conatin haemoglobin to carry oxygen
Describe the structure and function of lymphocytes
Structure:
- Have very little cytoplasm
- Have a large nucleus
Function:
- Produce antitoxins
- Produce antibodies
- Produce memory cells to provide active immunity
Describe the structure and function of phagocytes
Structure:
- Have a lobed nucleus
- Nucleus looks C-shaped
Function:
- carry out phagocytosis
- engulf and break down pathogens
Give 5 reasons why the alveoli are good exhange surfaces.
- Hint:*
- these 5 points are how the aveoli are specialised for gas exchange*
- They have a very good blood supply
- They have thin walls
- They are well ventilated
- They have a large surface area
- Their walls are permeable to gases
- Their walls have a moist layer of surfactant
Comare and contrast inhaled (inspired) and exhaled (expired) air.
- Hint:*
- You must make direct comparisons*
- e.g. inhaled air has….. but exhaled air has….*
- or*
- inhaled air has more/higher (or less/lower)…..*
- Inhaled air has more oxygen in it
- Inhaled air has less carbon dioxide in it
- Inhaled air is cooler/has a lower temperature
- Inhaled air has less water vapour
Define the term inhalation
The drawng in of air from the atmosphere into the lungs
Describe 7 key steps in inhalation
Define the term exhalation
The process of breathing out to remove air from the lungs
Describe the 7 key steps of exhalation
