Introduction to Cardiovascular Anatomy Flashcards
What is the basic function of the cardiovascular system?
To maintain a constant internal environment through homeostasis
It delivers oxygen and nutrients to cells and removes CO2 and waste
Why are high pressures needed in the arterial system?
To be able to pump blood to the extremities
Where does gas exchange occur in the cardiovascular system?
At the capillary bed in the organ
Why does the venous system require valves?
They prevent the backflow of blood as venous blood is acting against gravity
Why is the heart referred to as a ‘dual-action’ pump?
It has 2 circulations:
Pulmonary circulation concerns blood going to and from the heart
Systemic circulation concerns blood going to the rest of the body
What are the 2 pumps in the ‘dual-action’ pump system?
Pump 1 is the RA and RV
Pump 2 is the LA and LV
What are the 2 functional parts of the cardiovascular system?
- conducting system
2. exchange system
What is the conducting system of the cardiovascular system?
The vasculature (tubes)
Arteries carry blood away from the heart and veins carry blood towards the ehart
What is the exchange system of the cardiovascular system?
The capillary beds which have thin walls where exchange of gases and nutrients can occur
How is a continuous exchange system between the blood and extracellular fluid formed?
The capillary beds link the smallest arterioles with the smallest venules
How does the structure of the heart allow for efficiency?
Why?
Right side of heart deals with deoxygenated blood and left side deals with oxygenated blood
If the blood was mixed, some structures would not receive as much oxygen
How are the atria specialised to their function?
What is this function?
The atria receive blood
They are specialised to this function as they can distend
How does the right atrium receive blood?
What then happens to this blood?
It receives deoxygenated blood from the superior and inferior vena cavae
This blood passes through the atrioventricular valve into the right ventricle
What happens to the blood after it has entered the right ventricle?
The ventricle ejects blood towards the lungs via the pulmonary trunk
The pulmonary trunk then splits into the right and left pulmonary arteries
After reoxygenation at the lungs, how does the blood return to the heart?
It returns to the left atrium via pulmonary veins
It then passes through the atrioventricular valve into the left ventricle
What is systole?
Systole occurs when the muscles in the heart contract
Atrial systole occurs when the atria contract and ventricular systole occurs when the ventricles contract
What is diastole?
The period when the heart chambers are relaxed and receiving blood
What is the role of the interatrial septum?
It separates the right and left atria to prevent the mixing of blood
What are pectinate muscles and what is their role?
They are muscular elevations in the wall of the atria
They prevent the atria from over-distending
What is the function of the atrial auricle?
It acts as a reserve for when there is increased blood flow
It allows the atrium to receive a bit of extra blood
What is the crista terminalis?
It is an elevation which separates the smooth and the rougher part of the right atrium
What is the fossa ovalis?
It is an indentation on the right atrial wall
it had an importance in foetal circulation
What is the role of the coronary sinus in the right atrium?
Venous blood draining from the coronary supply to the heart enters the right atrium via the coronary sinus
What causes the atrioventricular valve to open?
what is a common misconception?
Tendinous cords DO NOT pull the valve open
The force of the atria contracting pushes blood through the valve