Anatomy and physiology- Cardiovascular system Flashcards
what are the two main blood vessel circuit’s
- Pulmonary Circuit
2. Sytemic Circuit
What are the three major types of blood vessels
- Arteries-carry blood away from the heart
- Capillaries- enable exchange of water and chemicals between blood and tissues
- Veins- carry blood from capillaries back to the heart
What is the Tunica intima (inner layer)
the thinnest layer that allows for nutrients and gases to be exchanged when blood reaches the capillaries
What is the Tunica media (middle layer)
This is the muscular middle layer and allows blood vessels to constrict and dilate to adjust the volume of blood.
What is Tunica externa (external layer)
This is mainly composed of connective tissue and serves to protect the vessel and anchor the blood vessel to nearby organs, giving them stability.
Both arteries and veins have the same three distinct tissue layers, What are these
Tunica intima (inner layer) Tunica media (middle layer) Tunica externa (external layer)
What is the heart made from
myocardium
How many chambers are in the heart
Four:
2 upper atriums
2 lower ventricles
Why do ventricles have thicker walls than the atriums
because blood is pumped out of the heart at greater pressure from these chambers compared to the atria.
What are the atria?
The two upper chambers in the heart, which receive blood from the veins and push it into the ventricles
What are the ventricles
The two lower chambers of the heart that pumps blood out of the heart and into the circulatory system.
What is the septum
A strong muscular wall that divides the two sides of the heart
How is blood flow controlled through the heart?
Four one way valves control blood flow through the heart chambers and prevent the backflow of blood.
Label the heart chambers
- Upper body
- Left atrium
- Right atrium
- Left Ventricle
- Right ventricle
- Lower body
what is The pericardium?
A double-walled sac containing the heart, and comprises the fibrous outer layer and the serous inner layer
What are the functions of the pericardium
Fixes the heart in position
Gives protection against infection
Provides the lubrication for the heart
What are the two layers of the pericardium
Fibrous pericardium - It is made up of connective tissue and acts to protect the heart
The serous pericardium,
what are the two layers of the the serous pericardium,
The parietal pericardium
The visceral pericardium
Extra info: In between the parietal and visceral layers there is a potential space called the pericardial cavity, which contains a supply of lubricating fluid known as pericardial fluid
What are the three layers of the heart wall
Epicardium
Myocardium
Endocardium
what is the the epicardium?
The epicardium is the outermost layer of the heart wall and is just another name for the visceral layer of the pericardium. Thus, the epicardium helps to lubricate and protect the outside of the heart.
what is the myocardium?
The myocardium is the muscular middle layer of the heart wall that contains the cardiac muscle tissue. Myocardium makes up the majority of the thickness and mass of the heart wall and is the part of the heart responsible for pumping blood.
What is the endocardium?
The endocardium is a thin layer of cells that lines the inside of the heart. The endocardium is very smooth and is responsible for keeping blood from sticking to the inside of the heart and forming potentially deadly blood clots.
The human circulatory system is a double system, What are the two separate systems of blood flow?
The left side of the heart deals with systemic circulation
The right side of the heart deals with pulmonary circulation
What are the 5 great vessels
Superior vena cava Inferior vena cava Pulmonary artery Pulmonary vein Aorta
What does the superior vena cava do?
Return deoxygenated blood from circulation in the body and empty it into the right atrium
What does the Inferior vena cava do?
Return deoxygenated blood from circulation in the body and empty it into the right atrium
What does the Pulmonary artery do?
carries deoxygenated blood from the right ventricle into the lungs for oxygenation
What does the Pulmonary vein do?
Carry oxygenated blood from the lungs into the left atrium
What does the Aorta do?
The largest artery in the body - it carries oxygenated blood from the left ventricle of the heart into systemic circulation
How many valves are in the heart?
Four
2 Atrioventricular valves
2 Semilunar valves
What are the Atrioventricular valves and what do they do?
The tricuspid valve and mitral valve, which control blood flow from the atria to the ventricles
what are the Semilunar valves and what do they do?
The pulmonary valve and aortic valve, which control blood flow out of the ventricles
What is the structure of the tricuspid valve?
The tricuspid valve has three leaflets or cusps and is on the right side of the heart.
What are atrioventricular valves made of?
The atrioventricular valves are thin structures that are composed of endocardium and connective tissue
What is the structure of the mitral valve?
The mitral valve is also called the bicuspid valve because it contains two leaflets or cusps. The mitral valve gets its name from the resemblance to a bishop’s mitre (a type of hat).
What are semilunar valves made from
Flaps of endocardium and connective tissue reinforced by fibres which prevent the valves from turning inside out.
What is the structure of the pulmonary valve?
The pulmonary valve lies between the right ventricle and the pulmonary artery, and has three cusps.
What is the structure of the aortic valve
The aortic valve, which has three cusps, lies between the left ventricle and the aorta.
Explain heart sounds
Heart sounds are the noises generated by the beating heart and the resultant flow of blood through it. In healthy adults, there are two normal heart sounds, often described as a lub and a dub. The lub-dup sounds are created when the heart valves snap shut:
What are the different heart sounds
First sound occurs as Atrioventricular valves close (the first heart sound S1)
Second sound occurs when Semilunar valves close (the second heart sound S2)
In addition to these normal sounds, a variety of other sounds may be present including heart murmurs ect, that may signal cardiac problems - The rarer extra heart sounds are termed S3 and S4
what is the Cardiac cycle?
The cardiac cycle refers to all the events associated with blood flow through the heart
what is Diastole
relaxation of heart muscle
what is Systole
Contraction of heart muscle
What happens in Diastole?
All heart muscle in relaxation
All heart valves are closed
Blood returning to atria
What happens in Atrial systole
Atria in contraction
AV valves are open
Blood to ventricles
What happens in ventricular systole?
Ventricles in contraction
Semilunar valves are open
blood passing to arteries
What is the cardiac conduction system?
A group of specialised cardiac muscle cells in the walls of the heart that send signals to the heart muscle
What are the main components of the cardiac conduction system.
SA node (Sinoatrial node)
AV node (Atrioventricular node)
Bundle of His
Bundle branches
Purkinje fibers
what is Polarization
is the resting state of the myocardial wall when there is not electrical activity in the heart and is recorded on the ECG strip as a flatline.
what is Depolarization?
when the electrical system if the heart stimulates a myocardial cell, resulting in the contraction of the stimulated heart muscle.
What is Repolarization?
the process of reaching the resting state before they can electrically simulated again
what is Electrocardiography (ECG)
Electrocardiography is the process of producing an electrocardiogram (ECG), a recording - a graph ofvoltage versus time
what are the three main components to an ECG
The P wave, which represents thedepolarization of the atria.
The QRS complex, which represents thedepolarization of the ventricles.
The T wave, which represents therepolarization of the ventricles.
what is the aorta?
The aorta is the main and largest artery in the human body, originating from the left ventricle of the heart and extending down to the abdomen
what are the sections of the aorta?
The aorta starts from the heart as theACSENDING aorta(upwards) then makes a hairpin turn known as theAORTIC ARCH. Following the aortic arch, the aorta then travels as theDECSENDING aorta(downwards).
what are The two parts of the descending aorta?
The aorta begins to descend in the thoracic cavity, and consequently is known as theTHORACIC aorta.
After the aorta passes through the diaphragm, it is known as theABODMINAL aorta.
what are the four Aorta branches?
- Coronary arteries (supply the heart)
- Aortic arch (supply head, neck and arms)
- Descending thoracic aorta (supply ribs and some chest structures)
- Abdominal aorta (supply most major organs)
The entire blood supply of the brain depends on two sets of paired arteries.
what are these?
The internal carotid arteries that are branches of the common carotid arteries (dark red).
The vertebral arteries arise from the subclavian arteries (light red).
what is the Circle of Willis?
The terminal branches of the vertebral and internal carotid arteries all connect to form a circular blood vessel
what are three main (paired) constituents of the Circle of Willis?
Anterior cerebral arteries
Internal carotid arteries
Posterior cerebral arteries
To complete the circle of willis, two ‘connecting vessels’ are also present what are these?
Anterior communicating artery – connects the two anterior cerebral arteries.
Posterior communicating artery– this artery connects the internal carotid artery to the posterior cerebral artery
The gut is divisible into 3 parts what are these?
Foregut
Midgut
Hindgut
what atery supplies the foregut
celiac artery
what artery supplies the midgut
superior mesenteric artery
what artery supplies the hindgut?
inferior mesenteric artery.
What is the hepatic artery?
The hepatic artery (also termed proper hepatic artery) is the artery that supplies the liver and gallbladder
