Topic 2a- Blood and circulation Flashcards
What is the difference between the left and right side of the heart?
Left pumps oxygenated blood.
Right pumps deoxygenated blood.
Where does deoxygenated blood enter the heart?
Vena carva.
Where does deoxygenated blood go to the lungs from the heart?
Pulmonary artery.
Where does oxygenated blood from the lungs enter the heart?
Pulmonary vein.
Where does oxygenated blood leave the heart and go to the body?
Aorta.
What is the passage of blood through the heart?
From: deoxygenated blood entering heart.
To: deoxygenated blood going to lungs.
Deoxygenated blood - from vena carva into right atrium when the right atrium is relaxed.
Right ventricle relaxes- right atrium relaxes- blood forced into right ventricle.
Right ventricle contracts, atrioventricular valve contracts preventing blood from reentering the right atrium.
Semi lunar valves prevent the blood from flowing from the pulmonary artery to the right ventricle.
Blood heads for the lungs to become oxygenated.
What is the passage of blood through the heart?
From: oxygenated blood coming back from lungs into heart.
To: oxygenated blood leaving heart to be pumped around the body.
Oxygenated blood from the lungs enters the left atrium through the pulmonary vein when the left atrium is relaxed.
When the left ventricle relaxes the left atrium contracts forcing blood into the left ventricle through the atrioventricular valve.
The left ventricle contracts forcing blood out through the aorta. The semilunar valves prevent blood from going back into the left ventricle. From the aorta the oxygenated blood is pumped around the body.
Why is the heart referred to as a double pump?
Blood is pumped twice.
What is important to remember when labelling a diagram of the heart?
Left and right sides are switched around from our perspective because its looking from if someone else’s heart was facing you. Note that the left side of the heart has more muscle surrounding it.
What holds the atrioventricular valves and stops them from turning inside out?
Heart strings.
Do the left and right side of the heart move in synchrony?
Yes.
Why would a fish heart have a different structure to a human heart?
Fish heart is not a double pump like a human heart.
What are artificial pacemakers?
A small device that is put just under the skin of your chest (below your collarbone) to help your heart muscle pump blood regularly.
Where is the heart’s natural pacemaker and what does it do?
In the right atrium wall, it sends out electrical signals to the heart muscles to the heart muscle to ensure that your heart beats continuously throughout your life.
How does an artificial pacemaker work?
It has a pulse generator and one or more leads.
The leads connect the inner wall (or sometimes the outer surface of your heart) with small metal electrodes.
What is coronary heart disease?
Where the arteries that supply blood to the heart muscle (the coronary arteries) get blocked by layers of fatty material building up.
What are the effects of coronary heart disease?
Restricted blood flow due to arteries narrowing resulting in a lack of oxygen to the heart muscle which can lead to a heart attack.
What are stents?
Stents are wire mesh tubes that can be inserted into arteries to widen them and keep them open. They can be used to treat coronary heart disease for example.
What are advantages / disadvantages of stents?
ADVANTAGES:
Long term
Lower risk of heart attack
Relatively quick recovery time from surgery
DISADVANTAGES:
Risk of complications during operation
Risk of infection from surgery
Risk of patients developing thrombosis (blood clot near stent).
What are statins?
Statins are drugs that can reduce the amount of cholesterol in the blood. Although cholesterol is an essential lipid your body needs to function, however too much of it (specifically LDL cholesterol) can lead to heart problems.
What are advantages / disadvantages of statins?
ADVANTAGES:
Can reduce the risk of strokes, coronary heart disease and heart disease.
Can increase the amount of “good” (HDL) cholesterol in blood.
DISADVANTAGES:
Long term drug that must be taken regularly.
Possible negative side-effects (e.g. headaches)
Can cause serious side effects: kidney failure, liver damage and memory loss.
Effect of statins isn’t instant.
What is an artificial heart?
If a person has heart failure doctors may transplant a donor heart from someone that has recently died, however if this is not possible, a doctor may use an artificial heart.
Artificial hearts are mechanical devices that pump blood for a person whose own heart has failed.
What are the advantages / disadvantages of an artificial heart?
ADVANTAGES:
Less likely to be rejected by immune system than a donor heart.
DISADVANTAGES:
Surgery can lead to bleeding and infection.
Don’t work as well as donor ones.
Blood doesn’t flow as smoothly as in donor hearts.
Patient has to take drugs to ensure a clot doesn’t occur. This can cause problems if they bleed when hurt since the blood can’t clot properly to heal the wounds.
Artificial heart may be uncomfortable for the patient.
What are the two types of replacement heart valve and when would they be used?
Biological valves or mechanical valves.
When a valve may not open properly or be leaky resulting in poor circulation.
What is artificial blood?
A blood substitute e.g. a salt solution (saline) used to replace the lost volume of blood.
What is cardiovascular disease?
Cardiovascular disease is a term used to describe diseases of the heart or bloodvessels.
What are the features of arteries? (8)
Blood flow from heart.
High oxygen content.
Low carbon dioxide content.
High blood pressure.
High speed of blood flow.
Pulse.
Thick walls.
No valves.
What are the features of veins? (8)
Blood flow to heart.
Low oxygen content.
High carbon dioxide content.
Low blood pressure.
Slow speed of blood flow.
No pulse.
Thin walls.
Lots of valves.
What is a capillary?
One of the smallest blood vessels that link to arteries and veins.
What substances needed by cells in the body tissues pass out of the blood through walls of the capillaries?
Oxygen, glucose, other soluble products of digestion.
What percentage of the blood is blood cells and what percentage is plasma?
45% blood cells
55% plasma
What is the function of red blood cells?
Carry oxygen.
What is the function of white blood cells?
Carry out immune response.
What are the two types of white blood cells? What do they do?
Phagocytes (engulf and digest bacteria) and lymphocytes (make antibodies).
What is plasma made from?
90% water
Dissolved solutes: proteins, hormones, products of digestion, minerals and waste.
What are the features of red blood cells and how do they make the cell well adapted for its function?
Biconcave shape gives it a large surface area to volume ratio.
It is able to carry large amounts of haemoglobin.
It has no nucleus allowing for more space.
What is haemoglobin?
Haemoglobin is a red protein responsible for transporting oxygen in the blood.
What is oxyhaemoglobin?
Where oxygen has binded with haemoglobin.
What are the stages of haemoglobin being transported around the body?
From: In the lungs
To: To the lungs again
In the lungs, haemoglobin binds with oxygen.
Oxyhaemoglobin is formed.
The red blood cell is now bright red.
Blood carries the red blood cells to organs.
In the organs, the haemoglobin releases oxygen.
Oxygen diffuses to the cells.
The red cells are now dark red.
Blood carries the dark red, deoxygenated red blood cells back to the lungs.
What cells are involved in blood clotting?
Platlets.
What is blood clotting?
Blood clotting is a series of enzyme- controlled reactions resulting in the change of fibrinogen (a soluble blood protein) to fibrin (an insoluble blood protein,) which forms a network of fibres trapping blood cells and forming a clot. This clot then hardens to form a scab.
What is the term used when a white blood cell “engulfs” a bacterium?
Phagocytosis.
What do you call a fatty deposit that forms inside a blood vessel?
An athoroma.
What is angina?
When the blood supply to heart through arteries is restricted causing pain (a warning for a heart attack.)
What substance is needed for the formation of haemoglobin?
iron
