heart Flashcards
1
Q
human heart
where? surrounded by?
A
- size of human fist
- located in middle of chest
- protected by breastbone and vertebral column
- surrounded by fluid filled sac called pericardum
2
Q
how many chambers in mammalian hearts? how do they work?
A
- 4
- blood flows from atrium to ventricle
3
Q
double pump system
A
- mammalian hearts called this bc 2 contractions force blood through body in 2 diff. directions at the same time
- right side pumps to lungs
- left pumps to body
4
Q
name the heart valves
A
- 2 atrioventricular valves
- aortic valve
- pulmonary valve
5
Q
atrioventricular valves
what do they do
A
- tricuspid and mitral
- prevent blood from entering atria when heart beats
6
Q
aortic valve
A
prevents blood from moving from aorta to left ventricle when heart not beating
7
Q
pulmonary valve
A
prevents blood from moving from pulmonary artery into right ventricle when heart not beating
8
Q
pulmonary circuit
A
- right atrium and ventricle
- receive and pump oxygen-poor blood to lungs
9
Q
systemic circuit
A
- left atrium and ventricle
- receive and pump oxygen-rich blood to body
10
Q
lubb dubb sound caused by…
A
- lubb: atrioventricular valves closing as ventricles contract
- dubb: pulmonary and aortic valves closing as ventricles relax
11
Q
heartbeat
A
- initiated in cluster of cells in right atrium called sinoatrial node (SA)
- “pacemaker”
- gives signals to set normal rhythm of heartbeat, which reach atrioventricular node
12
Q
Purkinje fibers
A
- line the septum and heart muscles from the atrioventricular node
- conduct impulses for heartbeat
13
Q
ECG/EKG
A
- electrocardiograph
- heartbeat is electrically simulated
- electrodes detect heart activity through body
14
Q
cardiovascular diseases
A
- athersclerosis: buildup of plaque in arteries
- coronary heart disease: atherosclerosis of arteries that provide heart muscle (leads to heart attack)
- stroke: atherosclerosis in arteries supplying brain
