M2: Heart Anatomy and Histology Flashcards
3 entry points for blood into R atrium
superior vena cava
inferior vena cava
openining of coronary sinus
Blood flow process
- Superior and inferior cava
- R atrium
- tricuspid (atrioventricular) valve
- R ventricle
- pulmonary semilunar valves
- pulmonary trunk
- pulmonary arteries
- lungs
- pulmonary veins
- L atrium
- bicuspid (mitral) valve
- L ventricle
- aortic semilunar valves
- aorta
for coronary circulation - coronary arteries
- heart tissue
- coronary veins
for systemic circulation - body tissues
what are the cusps in heart valves made of?
dense connective tissue covered by endocardium
chordae tendinae
- tendons in ventricles attached to papillary muscles (extension of cardiac tissue) and atrioventricular valves.
- when heart contracts, papillary muscles contract andf pull on tendons, ensuring valve does not fold back up into atrium
skeleton of the heart
plate of fibrous connective tissue between atria and ventricles
- contains FIBROUS RINGS around valves for support, electrical insulation between atria and ventricles, and muscle attachment
cardiac muscle cell structure
- elongated, branching cells
- contain actin and myosin filaments
- central nuclei
- a lot of mitochonria
- INTERCALATED DISKS: specialized cell-to cell contacts (bumpy ridges)
- DESMOSOMES: strong “staples” in intercolated disks to connect them
- GAP JUNCTIONS
differences between cardiac and skeletal muscles
cardiac muscle has
- larger and less frequent transverse tubules (signls SR to release Ca+), located at Z disk. Makes contraction slower, but works with regular heart rhythm.
difference between papillary and pectinate muscles
pectinate: atria
papillary: ventricles
where is the highest pressure in circulatory system and why?
aorta
because we need a high resting pressure to push blood throughout the entire body
