Circulatory System Flashcards
What are the 3major components of the circulatory system?
Blood, Heart + Blood vessels
What is the circulatory systems function?
Carries numerous materials found the body
E.g oxygen, co2, waste (urea), heat, hormones, digested food etc
What are the steps of double circulation?
1) deoxygenated blood enters the heart
2) blood is pumped to lungs to pick up oxygen
3) blood is oxygenated and travels back to heart.
4) blood is pumped around body (every cell gets oxygen so that every cell can carry out respiration)
What is pulmonary circulation?
Blood flowing through right side of the heart and going to the lungs
What is systemic circulation?
Blood flowing through left side of the heart and going round rest of the body
Name the 3 types of blood vessels
Arteries, Veins, Capillaries
What do arteries do? (+ What do they have that help carry out their jobs)
Carry blood away from the heart
-muscular, thick walls to withstand high pressure
-no valves
-pulse created by heart pumping + contraction of heart muscle
-strong walls
What do veins do? (+ What do they have that help carry out their jobs)
Carry blood towards the heart
-thinner, less muscular walls as blood is at very low pressure
-valves to stop blood flowing back
-no pulse
-flexible walls
What do capillaries do? (+ What do they have that help carry out their jobs)
Sites of exchange (co2, oxygen)
-very thin walls
-no valves
-no pulse
-delicate and easily broken
How is a pulse created?
By heart pumping + contraction of heart muscle
Where is aorta
Left side of heart
Where is vena cava
Right side of heart
Takes deoxygenated blood to heart
Where is hepatic vein
Liver
Takes blood from liver to heart
Where is hepatic artery
Liver
Where is hepatic portal vein
Liver
Carries blood stomach/intestines to liver
Where is gastric artery
Stomach
Where is mesentric artery?
Intestines
Where is renal artery?
Kidneys
Where is renal vein?
Kidneys
Where is iliac artery?
Lower organs (eg legs)
Where is iliac vein?
Lower organs (pelvis)
What is the heart? (What, where, etc)
4 chambered muscular pump, found left of the sternum
What is the wall of the heart made from?
Cardiac muscle. Which is is supplied with blood via the coronary arteries
What is the septum? (Function)
Prevents oxygenated and deoxygenated blood from mixing, improving efficiency.
What are valves?
Ensure blood flows in one direction only. Stop blood flowing backwards (clot)
Describe the different types of valves
One type is found between atria and ventricles. Ensure blood flows in one direction only.
Also, there are valves at points where blood leaves ventricles. These stop blood flowing back into heart between heart beats. Closing of valves cause heart sounds
Which ventricle has thickest wall and why?
Left ventricle
It has to generate enough pressure to pump blood the greatest distance.
Right ventricle wall is thinner as it only pumps blood to lungs
What is the thickness of atria walls and why?
Thin walls.
They don’t pump blood a great distance
Name the 4 main valves and where they are
Tricuspid valve, pulmonary valve, aortic valve and mitral valve
Tricuspid- right atrium to right ventricle
Pulmonary- between right ventricle and pulmonary artery
Aortic- final valve encountered by oxygenated blood as it leaves heart
Mitral- between left atrium + left ventricle
Where is bicuspid valve
Between left atrium + ventricle
What are the 4 main components of the blood?
Red blood cells, white blood cells, platelets + plasma
Describe red blood cells (function + appearance etc)
Transports oxygen around the body
Very small, no nucleus
Biconcave shape, (giving large SA:VOL ratio)
Contain haemoglobin
Oxygen+haemoglobin—> oxyhaemoglobin (bright red)
Describe white blood cells (function + appearance etc)
Larger than red blood cells, have nucleus
Come in many different types
Protect us from infection, fights disease
Describe platelets (function + appearance etc)
Cell fragments
Function- blood clotting
Goes to damaged site + forms network of fibres
Red blood cells get caught + form a clot which hardens into a scan which stops blood loss + keeps bacteria out
Describe plasma (function + appearance etc)
Yellow liquid
Makes up approx 55% blood volume
Contains nutrients, hormones, wastes etc
Transports co2, glucose, hormones, cells etc
