Chapter 18 Flashcards
(42 cards)
What is the function of the heart?
Pump blood through the 2 circuits
Which side is the pulmonary circuit on?
Right
Which side is the systemic circuit on?
Left
What is the heart?
Biological pump
What is the pressure of the pulmonary circuit?
Low pressure: 2 - 25 mmHg
Where does the pulmonary circuit deliver blood to?
oxygen-poor blood to lungs and oxygen-rich blood to systemic circuit
What is the pressure of the systemic circuit?
High pressure: 2 - 120 mmHg
Where does the systemic circuit deliver blood to?
oxygen-rich blood to organs and tissues and oxygen-poor blood to pulmonary circuit
How does blood decline as it goes through the heart?
arteries –> capillaries –> veins –> atria
Why is the pulmonary circuit low pressure?
don’t have to do a lot to fight gravity because you aren’t going very far
Where does blood return to?
opposite side of the heart
How does blood flow?
down the concentration gradient
Where is the highest point of pressure?
aorta
Why is the systemic circuit high pressure?
Have to fight gravity to get blood to the brain
Name the 4 valves
- Pulmonary (semi-lunar) valve
- Tricuspid valve
- Aortic valve (semi-lunar)
- Mitral valve (bicuspid)
What 3 things does the atria do?
- Receives blood from veins
- Direct blood towards ventricle
- Contract and add a little bit more blood to the ventricle
What do the 4 valves do?
Control flow of blood into ventricles and atria. pressure controls valves
What is the cardiac skeleton?
made up of connective tissue to help hold valves in place.
dense irregular connective tissue.
separates atria from ventricles and stops action potentials
What is ring body?
dense tissue. everything connects to ring body and it holds everything in place
What are the valves made up of?
connective tissue and dense irregular connective tissue covered in epithelium
What are the AV valves made up of?
Connective tissue
What are chordae tenineae
heart strings, attached to papillary muscles in the ventricles
When do the chordae and papillary muscles work?
when the valves are closed
What does the state of the valve depend on?
pressures in the heart