Cardiovascular System And Disease Flashcards
What is the role of the heart?
To pump oxygenated blood around the body to allow for aerobic respiration?
What is the heart made of and why is it useful for the heart?
- Cardiac muscle
- Can contract continuously without tiring
How is nutrients supplied to the heart?
Via coronary arteries
Label the heart
Um idk look in your notebook page 3 of year 10 bio
What is the acronym for the route blood takes through the heart?
Vava Vava
Vena Cava
Atrium (right)
Ventricle (right)
Artery (Pulmonary)
-Oxygenated in lungs-
Vein (pulmonary)
Atrium (left)
Ventricle (left)
Aorta
Why is left ventricle muscles thicker than right?
Needs to push blood all around the body rather than just to the lungs, so stronger and bigger muscle
Why do we need valves?
To prevent backflow, maximising amount of oxygenated blood reaching tissues
How does a double circulatory system work?
- pulmonary circuit pumps deoxygenated blood to lungs and oxygenated back to heart
- systemic pumps oxygenated around the body and back to heart
Advantages of a double circulatory system?
Separates oxygenated and deoxygenated blood
Allows for higher pressure in systemic circuit, increasing rate of 0² delivery
What is Plasma?
The fluid in your blood
-Makes up ~55% of blood volume
-Transports hormones, nutrients, antibodies, C0² and other waste around body
-Distributes heat
What are platelets?
Cell fragments (not whole cells)
- essential for blood clotting
- produce enzymes for blood clotting
What are RBCs (Red blood cells)?
Oxygen carrying cells in blood
- small and flexible with no nucleus
- contain haemoglobin to bind to O²
- biconcave shape for large SA for gases to diffuse
What are WBCs (White blood cells)?
Large cells that defend against pathogens
- large nucleus
- lots of mitochondria
- Lymphocytes produce antibodies to neutralise pathogens
- Phagocytes ingest and destroy invading microorganisms
What do antitoxins do?
Neutralise toxins produced by pathogens
How is O² carried in our blood?
- binds to the red pigment haemoglobin in RBCs
- is a weak and reversible binding to form oxyhaemoglobin
- Oxygen + haemoglobin <=> oxyhaemoglobin
How is CO² carried in our blood?
- dissolves into plasma to form carbonic acid
- a small amount of CO² can also bind to haemoglobin
Features of arteries and their purpose?
- small lumen to maintain high pressure
- thick muscle walls containing elastic fibres
- carry blood away from heart to organs
- when blood passes through, they can stretch and then return to original shape
Features of veins and their purpose?
- large lumen
- thinner walls than arteries
- have valves to prevent backflow
- carry blood away from organs towards heart
Features of capillaries and their purpose?
- narrow
- very thin 1 cell thick walls to let substances easily diffuse between blood and cells and vice versa
- form a huge network of tiny vessels linking arteries and veins
Define cardiovascular disease
Any disease in heart or cardiovascular system
What is coronary heart disease?
When coronary arteries become narrowed by fatty deposits building up.
Can stop blood from flowing to heart, potentially causing a heart attack
What is HDL?
High density lipoprotein
Has a positive effect, taking excess cholesterol to liver to be disposed of
What is LDL?
Low density lipoprotein
Levels are raised by consuming too much saturated fats
Increases risk of heart disease and stroke
What are risk factors for coronary heart disease?
- diet high in saturated fats
- lack of exercise
- obesity
- stress
- alcohol
- nicotine
- genetics
What are symptoms of coronary heart disease?
- fatigue
- breathlessness/Inc. breathing rate
- muscle weakness
- high blood pressure (Inc. risk of fainting)
- Inc. heart rate
- heart attack
- stroke
How does a stent treat coronary heart disease?
Stent is a metal grid that is placed in an artery. A catheter with a balloon is inserted into the vessel.
When narrow section of artery is found, balloon is inflated, stent expands and keeps artery open, allowing blood and O² to flow freely around body
What are the benefits of a stent?
- lowers risk of heart attack
- works for a long period of time
- recovery time is quite short
What are the drawbacks of a stent?
- risk of a blood clot near stent
- risk of complications during surgery
- risk of infection
How do statins treat coronary heart disease?
They are a drug taken every day
- reduce LDL and promote production of HDL
What are the drawbacks of statins?
- can cause headaches, dizziness and nausea
- can cause kidney and liver damage if taken over a long period of time
How does an artificial heart treat coronary heart disease
It doesn’t!!
It’s a mechanical device that replaces the function of the heart, but is only temporary until a donor heart is found
What are the positives and negatives of an artificial heart?
Positives
- lower chance of rejection than donor heart
Negatives
- surgery can lead to bleeding out and infection
- doesn’t work as well as healthy heart
- risk of blood clots and strokes
- you must take blood thinning drugs
How does a heart transplant work?
If heart is severely damaged, it is necessary to save life.
- It is essential to find a don’t that matches the patient to prevent rejection
- Patient must take immunosuppressant drugs to prevent rejection, but this increases risk of infection
Where are pacemaker cells and what do they do?
- located in right atrium
- control heartbeat
Where do pacemakers go and how do they work
- sit under skin on chest
- replace role of pacemaker cells by firing electrical impulses into right atrium
What is tachychardia?
Heart beating to fast without reason
What is bradychardia?
Heart beating too slow without reason
What do you do if your valves get a hole 😨
Get a biological valve transplant from a human or pig heart or get a mechanical man made one
