Exam 4: The Heart Flashcards
Cardiovascular system
–Essential for life
–If it fails, often fatal outcome
–Composed of heart and blood vessels
–Circulates blood continuously to maintain homeostasis
Trasportation of the blood through the body
–Allows exchange of substances between capillaries and cells
–Perfusion
–Adequate perfusion
–Requires continual pumping of the heart and open vessels
Perfusion
delivery of blood per time per gram of tissue
Adequate Perfusion
sufficient blood delivered to maintain health of body cells
The Heart characteristics
–Center of the cardiovascular system
–Hollow, four-chambered organ
–Composed of two pumps
What are the two pumps that the heart is composed of
Right sided pump
Left sided pump
Right sided pump
–receives deoxygenated blood from body
–pumps it to the lungs
Left Sided Pump
–receives oxygenated blood from lungs
–pumps it to the body
What characterizes the left and right artium
Superior chambers for recieving blood
What characterizes the left and right ventricles
- inferior chambers for pumping blood away
- receive blood from respective atria
Heart: The Great Vessels functions
- transport blood directly to and from chambers
- continuous with each chamber
The Heart: The great vessels
pulmonary trunk
aorta
superior and inferior vena cava
Heart: Pulmonary Trunk Functions
- splits into pulmonary arteries
- receives deoxygenated blood from right ventricle
Heart: Aorta Function
•receives oxygenated blood from left ventricle
Heart: Superior and Inferior Vena Cava Function
•drain deoxygenated blood into right atrium
Heart: Pulmonary Veins
•drain oxygenated blood into left atrium
What are the 2 types of valves found in the heart?
Atriventricular
Semilunar
Atrioventricular Valves
- between atrium and ventricle of each side
- right AV valve
- left AV valve
Right AV valve
Tricuspid
Located between the right atrium and right ventricle
Left AV Valve
bicuspid or mitral
Located between the left atrium and left ventricle
Semilunar Valves Functions
- boundary between ventricle and arterial trunk
- open to allow blood to flow through heart
- close to prevent backflow
What are the two Semilunar Valves?
Pulmonary
Aortic
Where is the pulmonary smilunar valve located?
Between right ventricle and pulmonary trunk
Where is the aortic semilunar valve located?
Between left ventricle and the aorta
Circulation Routes: Pulmonary Circulation
- carries deoxygenated blood from right side of heart
- goes through blood vessels to the lungs
- pick up of oxygen and release of carbon dioxide
- back through vessels to left side of heart
Circulation Routes: Systemic Circulation
- moves oxygenated blood from left side of heart
- moves through vessels to systemic cells
- exchange of nutrients, gases, and wastes
- returns blood in vessels to right side of heart
What is the basic pattern for blood flow?
•right heart ► lungs ►left heart ► systemic tissues ► right heart
Pericardium
–Membrane surrounding and protecting the heart
–Confines while still allowing free movement
–2 main parts
What are the two parts of the pericardium?
- Fibrous pericardium
- Serous pericardium
Fibrous Pericardium
tough
inelastic
dense irregular connective tissue – prevents overstretching
protection
anchorage
Serous Pericardium
thinner
more delicate membrane double layer:
– parietal layer fused to fibrous pericardium
– visceral layer also called epicardium
What does the pericardial fluid do? Where is it secreted?
Reduces friction
secreted into pericardial cavity
What are the three layers of the heart wall?
Epicardium
Myocardium
Endocardium
Epicardium
(visceral layer of serous pericardium)
- outermost heart layer
- serous membrane of simple squamous epithelium
- underlying areolar connective tissue
Myocardium
- middle heart layer
- composed of cardiac muscle tissue
- thickest of three layers
- contraction generates force to pump blood
- may change in thickness with age