The Cardiovascular System; The Respiratory System Flashcards
circulatory path of blood - systemic circulation
left ventricle –> aorta –> arteries —> arterioles –> capillaries –> venules –> veins –> superior and inferior vena cava –> right atrium
circulatory path of blood - pulmonary circulation
right atrium –> right ventricle –> pulmonary arteries –> arterioles –> capillaries of lungs –> venules –> veins –> pulmonary veins to heart –> left atrium –> left ventricle
sinoatrial node (SA node)
group of specialized cardiac muscle cells in right atrium
pace the heart contractions
autorhythmic, spreading its contractions to the surounding cardiac muscles via electrical synapses made from gap junctions
vagus nerve
innervates the SA node, slows the contractions (SA node is faster than normal heartbeats)
parasympathetic nerve
innervates digestive system (increases digestive activity)
atrioventricular node (AV node)
in interatrial septa
action potential from SA node spreads here
bundle of His
conductive fibers in wall separating ventricles
action potential here after AV node
purkinje fibers
conducting fibers in ventricles
action potential spread through gap junctions from one cardiac muscle to next
allow for more unified, stronger contraction
arteries vs. veins
lumen of veins/venules larger than artieris
veins have larger volume of blood
cross sectional area of veins larger
blood moves the slowest through the ____
capillaries (blood not an ideal flow)
blood moves fastest through the ….
aorta and venae cavae (smallest total cross sectional area)
total cross-sectional area of capillaries
far greater than arteries and veins
blood pressure lowest in….
veins…? capillaries ?
a problem in microtubule production might result in…
problems in breathing, fertility, or circulation of cerebrospinal fluid
(microtubules found in cilia ,ciliated cells in respiratory tract, fallopian tubes, ependymal cells of spinal cord)
pharynx
throat, passageway for food and air
larynx
voice box
epiglottis
prevents good from entering trachea
hemoglobin
binds 98% of the oxygen in the blood reversibly
inside erythrocytes
iron at center of heme cofactor
4 subunits –> 4 iron atoms –> can bind 4 O2 molecules
as O2 pressure increases, the O2 saturation of hemoglobin…
increases sigmoidally
oxygen dissociation curve is shifted to the right (lowering of hemoglobin’s affinity for oxygen) by….
increase in carbon dioxide pressure, hydrogen ion concentration, temperature
carbonic anhydrase
enzyme that governs bicarbonate ion formation
inside red blood cells
CO2 + H2O –> HCO3- + H+
most carbon dioxide carried as
bicarbonate
in acidosis, the body compensates by _____ the breathing rate to ….
increasing the breathing rate to expel carbon dioxide and raise pH of blood
lymph system is an ____ system
open system - fluid enters at one end and leaves at the other
blood is a ___ tissue
connective tissue - contains cells and matrix
