Section 3 Flashcards
What is the distribution of cardiac output?
Refers to the amount of blood (%) in the arterial and venous system and a given time.
Typically, 30-35% of total blood resides in arterial system, whereas 60-65% resides in the venous system.
What does pulmonary circulation function to do?
- Carries deoxygenated blood from the heart to the lungs for oxygenation (gas exchange)
- Returns oxygenated blood back from the lungs to the heart
What does systemic circulation function to do?
- Carries oxygenated blood from the heart to other organ systems/tissues of the body, EXCEPT the lungs
- Deoxygenated blood from the tissues returns to the heart
What is the anatomical position/shape of the heart?
- the heart resides in the mediastinum (a space between the lungs in the thorax)
- as a result, the heart has different borders and surfaces depending on the areas that it comes into close contact with
- the shape of the heart resembles an inverted pear fruit
- the most inferior and lateral portion of the heart on the left is known as the apex
What is the pericardium of the heart?
The heart has various layers on top of it, referred to as covering, or the pericardium of the heart.
What are the types of layers of pericardium?
- Fibrous pericardium is the most external covering
- Serous pericardium, is further divided into parietal and visceral pericardium. Between these two layers, there is pericardial space filled with pericardial fluid. Pericardial fluid decreases friction between the two layers when the heart beats
Altogether, the pericardium consists of THREE layers
What are the chambers of the heart?
- Right atrium
- Left atrium
- Right ventricle
- Left ventricle
Where is the interatrial septum of the atria?
- it is the wall between the left and right atria where the fossa ovalis is found
Where is the fossa ovalis of the atria?
- it is a depression in the interatrial septum of the right atrium
- it is an embryological remnant of the fetal foramen ovale, an opening which allowed movement of blood from the right to the left atrium during fetal life
Where are the auricles of the atria?
- they are extensions or pouches that project above the chambers of the left and right atria
- they increase the capacity of each atrium
Where is the atrioventricular groove?
- it is the depression between the atria and ventricles encircling the heart, AKA the coronary sulcus
- it separates the atria from the ventricles
- also houses the coronary vessels
What is are the functions of the ventricles of the heart?
- The right ventricle pumps blood to the lungs to become oxygenated
- The left ventricle pumps oxygenated blood to the rest of the body
Where is the interventricular sulcus of the ventricles?
- it is a groove on the external surface of the heart that separates the right ventricle from the left ventricle
- it sits above the interventricular septum
Where is the interventricular septum?
- it is the wall between the left and right ventricle
Where is the trabeculae carneae?
- they are the irregular muscular ridges on the internal walls of each ventricle
- formed by the large ventricular muscles