chapter 18 Flashcards
Blood circulation
any of the blood vessels that carry blood to and from the lungs (gas exchange)
pulmonary circuit
pump oxygen poor blood from right side of the heart to the lungs
pulmonary arteries
pump oxygenated blood from the lungs to the left side of the heart (carry oxygenated blood from lung tissue back to the heart)
pulmonary veins
any of the blood vessels that carry blood to and from the any other body tissues
systemic circuit (general circulation)
oxygenated blood leaves heart through……. to body tissues. Then gas exchange occurs
aorta and its branches
oxygen poor blood returns to heart via…..
superior vena cava and inferior vena cava—> reenters pulmonary circuit
left side of heart is
systemic
right side of the heart is
pulmonic
systemic: oxygenated blood travels through….., oxygen poor blood travels through……
arteries, veins
Pulmonic: oxygenated blood travels through….., oxygen poor blood travels through…….
veins, arteries
the right side (pulmonic side) is …….. pressure
lower pressure. It doesn’t have to create a ton of pressure to move blood. Think about it your heart is very close to your lungs, so the destination is close so its low pressure
The left side (systemic) is …… pressure
higher pressure. The left side has to pump blood to every other part of your body. Has to pump a large amount of blood in your body over several feet depending how tall you are. The left side is more thicker
the heart is tipped where
thoracic cavity
the apex (inferior “tip” of the heart) points to….
left hip
coverings
Fibrous pericardium:
- outermost region
- function: prevents heart from filling with too much blood, anchors heart in chest cavity, protects heart
- not super flexible–> puts limits of how much blood can enter so it prevents walls from over stretching
- forms a wall to protect the heart–> if an individual has an infection the fibrous pericardium puts a physical wall around the heart to prevent spread of infection to the heart tissue
Serous pericardium
- internal portion
- function: divided into visceral and parietal layers-forms fluid filled sac around the heart
- separated by fluid so they can rub against each other to prevent them from being broken down
what are the 3 layers of heart wall
- Epicardium
- Myocardium
- Endocardium
epicardium
- outermost layer
- visceral layer of pericardium
- thin layer
myocardium
- middle layer
- contains cardiac muscle cells (prefix: myo)
- bulk of heart
- strong contractions of heart to repel the blood through either circuit
Endocardium
- innermost layer
- covers internal surfaces of heart, including valves
- continuous with linings of major blood vessels entering/ leaving heart
- thing, smooth, slick surface–> easy for blood to move across–> easier to move blood= less work for heart to do–> blood basically glides across it and enters and leaves the heart very easily
2 atria:
superior receiving chambers
receives oxygen poor blood from systemic circuit
right arium
* blood enters via superior and inferior vena cava, coronary sinus
recieves oxgenated blood from the lungs
left atrium
-blood enters via pulmonary veins
what are the three features of the atria?
- pectinate muscle–> increases contractile force of atrium without increasing mass of heart (helps maintain efficiency without making heart to bulky in the chest)
- auricles—> two “ears” sitting on the external surface of the heart. The atrium can receive more blood due to auricles
- fossa ovalis–> indentation in the left atrium. Marks where the foramen ovale used to be. Foramen ovale closes after birth and then forms the fossa ovalis
what are the two features of the ventricles?
1. Trabeculae carneae: ridges of muscle that assist with proper functioning of heart valves (prevetns blood from flowing in the wrong direction)
2. Papillary muscle: assist in opening/closing of the heart valves
prevetns backward flow of blood through the heart
Heart valves
what are the two types of heart valves?
- Atrioventricular (AV) valves
- semilunar valves
prevents backflow of blood from blood vessels into ventricles
Semilunar (SL) valves
detection of the electrical impulses generated in and transmitted by the heart
- Electrocardiogram (ECG)
- doctors can see heart activity
total volume of blood remainng in the ventricle after they have contracted
End systolic volume (ESV)
Total volume of blood in the ventricles before they contract
End Diastolic volume (EDV)
The total amount of blood pumped by ventricle in a single minute
Cardiac output
the maximum amount of blood that can be pumped in a single minute
Maximal cardiac output
2 ways to regualte heart rate
- autonomic nervous system input
- chemical regulation
