Circulatory & Respiratory Systems Flashcards
heart
- right side pumps deoxygenated blood into pulmonary circulation (towards lungs)
- left side pumps oxygenated blood into systemic circulation (thru body)
atria
-thin-walled upper chambers
ventricles
-muscular lower chambers
valves
- atrioventricular valve: b/w atria and ventricles, prevent back flow
- tricuspid valve: right side, 3 cusps
- mitral valve: left side, 2 cusps
- semilunar valve: b/w left ventricle and aorta & right ventricle and pulmonary artery
heart beat
made up of 2 phases, systole and diastole
systole
ventricles contract, forcing blood out of the heart into the lungs
diastole
cardiac muscle relaxation, during which blood drains into all 4 chambers
cardiac output
- total volume of blood the left ventricle pumps out per minute
- heart rate x stroke volume (vol of blood pumped out of left ventricle per contraction)
sinoatrial node (pacemaker)
- small mass of tissue in the right atrium
- spreads impulses thru atria, stimulating them to contract simultaneously
atrioventricular node
-slowly conducts impulses to the rest of the heart
bundle of His (AV bundle)
-after AV node impulse travels here then thru left and right bundle branches
Purkinje fibers
-after AV bundle impulses travel thru these in the walls of the ventricles and generates a strong contraction
ANS modifies the:
rate of heart contraction
arteries
thick-walled, muscular elastic vessels that transport oxygenated blood away from the heart, except the pulmonary artery (transports deoxygenated blood from the heart to lungs)
veins
- relatively thin-walled, inelastic vessels that conduct deoxygenated blood to the heart, except pulmonary vein (oxygenated blood from lungs to heart)
- have valves to prevent back flow
capillaries
-smallest diameter of the 3 vessels, RBC travel thru in single file line
lymph vessels
transport excess interstitial fluid (lymph) to the cardiovascular system
lacteals
smallest lymph vessels, collect fats (chylomicrons) from the villi and deliver them to blood, bypassing the liver
plasma
- liquid portion of blood
- mix of nutrients, salts, gases, wastes, hormones, and blood proteins
leukocytes
WBCs, protective functions
platelets
cell fragments that lack nuclei, involved in clot formation
erythrocytes
- RBCs, oxygen-carrying component of blood
- formed from stem cells in bone marrow
- disk-like shape that increases surface area for gas exchange and greater flexibility
- contains hemoglobin which binds oxygen (oxyhemoglobin)
2 groups of RBC antigens
ABO group and Rh factor
type AB
“universal recipient”, no antibodies so it won’t reject
type O
“universal donor”, no antigens so it will not elect a response form the recipients immune system
Rh factor
-important during pregnancy
transport of gases
- erythrocytes transport O2 (hemoglobin binds to O2)
- Hb also binds to CO2
transport of nutrients and waste
- AA and simple sugars are absorbed at intestinal capillaries and transported thru the body
- waste products diffuse into capillaries
platelet plug
-aggregation of platelets
thromboplastin
-clotting factor that converts plasma protein (prothrombin) to its active form (thrombin)
thrombin
converts fibrinogen into fibrin, which coats the damaged area and traps blood cells to form a clot
serum
fluid left after blood clotting
clotting cascade
complex series of reactions leading to clotting
respiratory system
air enters the lungs after traveling thru a series of respiratory airways (nose, pharynx, larynx, trachea, bronchi, bronchioles, and alveoli)
alveoli
air-filled sacs at the terminals of airway branches where gas exchange b/w lungs and circulatory system occur
ventilation
-process by which air is inhaled and exhaled
inhalation
- diaphragm contracts and flattens, and intercostal muscles contract pushing the rib cage and chest wall up and out
- thoracic cavity increases in volume and lungs explained and fill with air
exhalation
-diaphragm and intercostal muscles relax, decreases in thoracic volume forces air out of the alveoli and lungs deflate
surfactant
- protein complex excreted by cells in the lungs
- keeps lungs from collapsing
respiratory centers
-regulates ventilation, located in the medulla oblongata, which stimulates intercostal muscles or diaphragm to contract
chemoreceptors
-regulate oxygen-blood levels, indirectly stimulate the respiratory center
pulmonary capillaries
-surround the alveoli, gas exchange occurs by diffusion across these (from high pp to low pp)
total lung capacity
-max volume of air the lungs can hold
tidal volume
at rest, humans only breathe as much as needed, smaller capacity than total lung capacity
vital capacity
max amount of air a person can expel from the lungs after the deepest breath
inspiratory reserve volume
difference b/w vital capacity and the upper limit of tidal volume
expiratory reserve volume
difference b/w vital capacity and lower limit of tidal volume
residual volume
lungs will never normally empty completely (difference b/w vital capacity and total lung capacity)
