module 4 - lecture 10 Flashcards
cardiovascular system
includes blood (a fluid), blood vessels (tubes)
and the heart (a pump)
* To transport blood between the
heart, and organs and peripheral
tissues:
* Pulmonary Circuit – gas exchange
* Systemic Circuit – rest of body
functions of the blood in CV system
Functions of blood:
* Transport gases (O2 & CO2),
nutrients, hormones
* Regulate pH
* Prevent fluid loss via blood clotting
* Defence – white blood cells;
antibodies
* Maintain body temperature
(absorb & release heat)
Pericardium
Sac surrounding heart
* Fibrous & serous layers
* Contains fluid (pericardial fluid)
The Heart
Base
* superior; large veins and
arteries attached
* Apex
* inferior; pointed tip
Right atrium
receives blood from
systemic circuit; then empties into
right ventricle (then pumped into
pulmonary circuit)
Left atrium
receives blood from
pulmonary circuit; then empties
into left ventricle (then pumped into
systemic circuit)
Atria
receiving chambers
expandable
Atrioventricular Valves
Between atria and ventricles
* Fibrous tissue
* Cusps (leaflets)
* Right AV valve has three
* Left AV valve has two
* Chordae tendineae (tendinous
cords)
* Papillary muscles – anchor the
chordae tendineae
Semilunar Valves
- Between ventricles and
blood vessels - Aortic SL valve
- ventricle and aorta
- Pulmonary SL valve
- ventricle and pulmonary trunk
Endocardium
Lining inner surfaces of heart
* Endothelial cells (squamous)
Myocardium
“Cardiac Muscle”
* Muscular walls of heart
* Atria & ventricles
Cardiac muscle cells
- ‘Cardiomyocytes’
- Connected together at
specialized attachments
site called intercalated
discs
Epicardium
Outer surface of heart
* Visceral pericardium
* Blood vessels
‘Cardiac Cycle
- Diastole (di-aster-lee)
- relaxation of the ventricles
- AV valves open
- Systole (sister-lee)
- contraction of the ventricles
- AV valves closed
- During these phases, blood
moves through the heart;
valves open and close
