Term 2 Exam: The Cardiovascular System Flashcards
What are the two circulatory systems?
- Pulmonary
- Systemic (includes pulmonary)
What is the difference between arteries and veins?
Arteries: Carry blood away from the heart
- High in O2 in the systemic circulation
- Low in O2 in the Pulmonary circulation
Veins: Carry blood to the heart
- Low in O2 in the systemic circulation but high in O2 in the pulmonary circulation
Where does the heart lie?
in the mediastinum with 2/3 of its mass to the left of the midline
What is the fibrous pericardium? What are three functions
The superficial, tough, inelastic, dense irregular connective tissue
Functions:
- prevents overstretching of the heart
- provides protection
- anchors heart to mediastinum
What is the serous pericardium?
Thin, double serous membrane
Divided into parietal and visceral pericardium
What is Pericardial fluid?
Secretion in the pericardial cavity that reduces friction between serous membranes
What is the epicardium?
External layer of the mesothelium (simple squamous epithelium) and connective tissue (fibro-elastic and adipose)
What is the Myocardium?
middle, muscular layer
*95% of heart wall
What is the endocardium?
inner thin layer of epithelium
- Covers the valves and is continuous with the endothelium of blood vessels
What are four characteristics of the cardiac muscle fibers?
- shorter and less circular transverse sections than skeletal muscle
- branched
- intercalated discs containing desmosomes and gap junctions
- larger and more numerous mitochondria
what are the three major grooves (sulci) of the heart?
- Coronary sulcus
- Anterior interventricular sulcus
- Posterior interventricular sulcus
What are the two superior chambers of the heart?
Right and left atria
- Recieve blood returning to the heart via the veins
What are the two inferior chambers of the heart?
Right and left ventricles
- Powerful pumps
What does the pulmonary pump consist of?
Right atrium and Right Ventricle
Services the pulmonary circuit
-moves deoxygenated blood through the lungs
What does the systemic pump consist of?
Left atrium and left ventricle
- services the systemic circuit
- pumps oxygenated blood to all systems in the body
What is the coronary sinus?
Receives blood from the wall of the heart
What type of blood does the right atrium receive and from which three blood vessels?
The right atrium receives deoxygenated blood from:
- Superior Vena Cava
- Inferior Vena Cava
- Coronary Sinus
What separates the two atria?
Interatrial Septum
What is the Fossa Ovalis and from which fetal structure does it arise?
The fossa ovalis is a depression on the septum
It is a remnant of the foramen ovale of the fetal circulatory system
What is the valve between the right atrium and the right ventricle?
Right atrial ventricular valve (tricuspid valve)
* has three folds or flaps (cusps)
What are trabeculae carneae and what is the purpose?
Raised bundles of muscles that form deep ridges in the ventricles - allow ventricle to stretch (when filling with blood)
What structure separates the two ventricles?
The interventricular Septum
What structure does blood pass as it heads to the lungs via the pulmonary arteries?
Pulmonary valve
The left atrium receives _______ blood from four _________.
oxygenated blood from four pulmonary veins (2 for each lung).
