Ch 3 - Cardiorespiratory System Flashcards
Cardiovascular system
heart, lungs, and blood vessels
Mediastinum
space between lungs that contains all other organs of chest
Sinoatrial node
specialized area of cardiac tissue in right atrium; initiates electrical impulses that determine heart rate; pacemaker of the heart
Atrioventricular node
small mass of fibers in wall of right atrium; receives heartbeat impulses and directs them to ventricle walls
Atria
upper chambers of heart; receives blood from veins and forces it into ventricles
Ventricles
lower chambers of heart; receive blood from corresponding atrium and force it into arteries
Systemic side of heart
left side - pumps oxygenated blood to rest of body
Pulmonic side of heart
right side - receives deoxygenated blood and pumps it to lungs and then to left atrium
Stroke volume
amount of blood pumped out of heart with each contraction; difference between end-diastolic volume and end-systolic volume; around 70mL
End-diastolic volume
filled volume of ventricle before contraction; around 120mL
End-systolic volume
residual volume of blood in ventricle after ejection; around 50mL
Cardiact ouput (Q)
heart rate times stroke volume; overall performace of heart
Composition of blood
white cells, red cells, and platelets suspended in plasma; 55% plasma, 45% cells
Arteries
blood vessels that transport blood away from the heart
Veins
blood vessels that transport blood from capillaries toward the heart
Capillaries
smallest blood vessels; connect venules and arterioles; site of exchange of nutrients, water, and oxyen are taken up by cells for metabolism and waste and CO2 are exchanged back into blood
Aorta
largest artery
Arterioles
small branches of arteries; end in capillaries
Venules
very small veins that connect capillaries to larger veins
Respiratory system
lungs, airways, and respiratory muscles
Respiratory pump
bones and muscles that allow for proper respiratory mechanics
Inspiration
inhalation; active contraction of respiratory muscles
Expiration
exhalation; active or passive relaxation of respiratory muscles
Conducting airways
structures air travels through before entering respiratory airways
Diffusion
process of getting oxygen from environment to tissues of body
Alveolar sacs
where gases are transported in and out of bloodstream; clusters of sacs make up alveoli at ends of bronchioles
Respiratory airways
collect air from conducting airways; allow gases to be transferred in and out of bloodstream
Oxygen uptake
body’s use of oxygen; oxygen consumption
VO2
resting oxygen consumption; around 3.5mL/kg/min
Fick equation
VO2 = Q x (a-v)O2
VO2 max
max. oxygen consumption; best measure of cardiorespiratory fitness; highest rate of oxygen transport and utilization achieved at max. physical exertion; around 40-80mL/kg/min or 11-23 MET; estimated by Rockport Walk Test, Step Test, YMCA bike protocol test
Respiratory muscles
include scalene, SCM, LS, upper traps
Respiratory system
trachea, bronchi, alveoli, lungs
