Lab Exam 2 Physiology Flashcards
What structures form sarcomeres
alternating light and dark cross-bands that result from the arrangement of sarcomeres
intercalated disks
connect adjoining cells
specialized junctions
found in cardiac muscle
What is the EMG
an external recording of electrical activity of a muscle
records combined action potentials
Motor units
motor neuron & skeletal muscle fibers
increasing recruitment of motor units increases the number of muscle fibers activated and increases the force of the muscle
fetal shunts
two major shunts one between the right atrium and right ventricle and the other between the right and left atrium
one is called the foramen ovale which becomes the fossa ovalis and the other is the ductus arteriosus which becomes the ligamentum arteriosum
how do you calculate beats per minute
60/(t2-t1) (the seconds - R-R interval)
Waves
P wave - depolarization of atria
QRS wave- initial depolarization of ventricles
T wave- repolarization of ventricles
Intervals
PQ - atrial depolarization and delay at AV node
QT- beginning of Q to end of T ventricular excitation
ST- beginning s to beginning t plateau phase of ventricular action potential
TQ- end of t to beginning of Q ventricular cells back at their resting potential
Auscultation
listening to the sounds made by body structures as a method of diagnosis
systolic
diastolic
heart sounds
systole- ventricles contract
diastole- ventricular relaxation
lub- closure of atrioventricular valves during the isovolumetric contraction phase
dup- closure of semilunar valves during isovolumetric relaxation phase
Heart murmurs are caused by
improper functioning of heart valves
systolic murmurs vs diastolic murmurs
sm- occur between the first heart sound
dm- between second and first heart sound
aortic stenosis
systolic
narrow opening of aortic valve, sharp whooshing sound
mitral valve prolapse
systolic
leak in mitral valve, or valve is turned inside out
whoosh sound instead of lub
name of the device used to measure blood pressure
normal bp?
sphygmomanometer
120/75 mm Hg
what sounds or changes are associated with the systolic pressure reading and the diastolic reading
SP- blood begins to pulse through the partially opened artery which causes turbulent flow (tapping sounds)
DP- artery open smooth and quiet flow (sound disappears)
hypertension
chronically high blood pressure
heart works faster which increases strain
risk factor heart disease and stroke
sensed by baroreceptors in aortic and carotid arteries
MAP
MAP = CO X TPR MAP= diastolic + 1/3 systolic
What are OPD, examples, test
FEV (forced expiratory test) is for OPD
healthy is 75%-85%
asthma, emphysema, bronchitis
OPD is constricting or blockage of bronchioles
Hematocrit
% of the volume of RBC
women- 38%-46%
men- 42% to 54%
low = anemia
expiratory reserve volume
tidal volume
inspiratory reserve volume
vital capacity
ERV- maximum volume that can be expired forcefully from lungs following relaxed expiration
Vt- volume of air that passes into and out of lungs in a normal relaxed breathing
IRV- maximum air that can be inspired into the lungs following normal inspiration
VC- maximum ventilation volume (vt+IRV+ERV)
Specific gravity
is the measure of the density of a solution, density relative to H20
in urine reflects kidneys ability to form a dilute or concentrated urine
more concentrated = higher specific gravity
increase in SG usually occurs during dehydration or salt loading (increases plasma osmolarity)
main waste product of protein (nitrogen) and lipid metabolism
is glucose normally present in the urine
protein- albumin
lipid- ketones
No, glucose in the urine is glycosuria and is caused by diabetes
Renal clearance
what does it indicate
volume of plasma from which a substance is completely removed by the kidney in a given amount of time
less= reabsorption
more= secretion
Clearance = (Concentration in the urine) x (Urine flow rate) / (Concentration in the plasma)
= U x V / P
Pancreas
endocrine & exocrine
exocrine- enzymes to break down proteins, lipids, carbs, nucleic acids
endocrine insulin and glucagon
What physiological variable that pertains to renal function is approximately equal to the
clearance of inulin?
Glomerular filtration rate (GFR)
