PHYSIOLOGY Flashcards
An increase in the heart rate increases the force of contraction generated by the myocardial cells with each heartbeat refers to
Treppe phenomenon
What phases are NOT present in the SA node action potential?
Phases 1 and 2
The rapid diffusion of ions that result in propagation of the action potential in cardiac muscle fibers is due to the presence of
Gap junctions
A carotid pulse called pulsus parvus et tardus is seen in what disease?
Aortic stenosis
What ion is responsible for the self-excitation of the sinus nodal fibers?
Sodium
An accentuated decrease in systolic arterial pressure of >10 mmHg during inspiration
Pulsus paradoxus
Wide, fixed splitting of the second heart sound is characteristically seen in what condition
Atrial septal defect
Pt: ventricular tachycardia
PE: hyperkeratosis of his hands and feet and that he had thick, wool-like hair.
Naxos disease
infero-posterior infarction and hypotension. What reflex?
Bezold- Jarish reflex
In what phase of the cardiac volume-pressure curve are the atrioventricular valves open while the semilunar valves are closed?
Period of filling
A beat to beat alternation of one or more components of the ECG signal, together with sinus tachycardia is a relatively specific sign of what condition
Pericardial effusion with tamponade
What ions are responsible for the plateau phase in the ventricular action potential
Calcium
Brain waves found in those who are awake (eyes closed)
Alpha waves
8-12 Hz
(Awake and relaxed)
<4- delta
<8 - theta
>12 - beta
Brain waves found in those who are awake (eyes open)
Beta waves
>12 Hz
Brain waves found in those who are alert
Beta wave
Brain waves found in those who are awake and relaxed
Alpha wave
Brain waves found in those who are soundly sleeping
Delta/ slow waves
Deep sleep
Brain waves found in those who have hepatic/ uremic encephalopathy
Delta / slow waves
(Requirement on those who have hepatic encephalopathy + asterixis/negative myoclonus)
Brain waves found in those who are in REM sleep
Beta wave
Brain waves found in those who are in stage 4 slow wave sleep
Delta wave
Brain waves that are strong and of low frequency
Most sleep during each night
Slow wave or non REM Sleep
Eyes undergo rapid movements even though the person is still asleep
25% of sleep time
Recurs about every 90 mins
Rapid eye movement (REM Sleep)
Not so restful
Associated with vivid dreams?
REM or Non REM?
REM sleep
Deep, restful sleep during first hour of sleep after having been awake for many hours
Non-REM sleep
Paradoxical, desynchronized sleep
REM Sleep
Raphe nuclei produce what neurotransmitter?
Serotonin
Lesion in raphe nuclei
Bilateral lesion in the medial rostral suprachiasmal area in the anterior hypothalamus
high state of wakefullness
Important neurons in arousal and wakefulness
Orexin neuron/ hypocretin
Produced in the hypothalamus
Loss or destruction of Orexin Producing neurons cause?
Narcolepsy
Weight of kidney
150 g
Most common injured organs in blunt abdominal trauma
Liver and spleen
Position of kidneys
Retroperitoneal
Right kidneys more CAUDAL
What is the most common kidney chosen for renal transplant?
LEFT kidney
Left renal vein in Longer
All chronic kidney disease has atrophied kidney except?
HIV
DM nephropathy
Amyloidosis
Functional unit of kidney
Nephron
Juxtaglomerular apparatus (3)
JG cells
Macula densa
Mesangial cells
Cell that secretes Renin
JG cells
Senses changes in volume and decrease in NaCl concentration
“Na sensor”
Macula densa
Basic renal processes
Glomerular Filtration
Tubular Reabsorption
Tubular Secretion
Normal protein content of urine
Zero
Usual daily urine output
720 - 1440mL
(700-1500)
Bladder muscle responsible for urination
Detrusor muscle
Effect of sympathetic nervous system in the bladder
Fill the bladder
(Sympathy is Feeling)
Effect of parasympathetic nervous system in the bladder
Emptying of bladder
(No pera - empty)
Erection
Para or sympa?
Parasympathetic
(point)
Ejaculation
Para or sympa?
Sympathetic
(Shoot)
Parasite that causes urinary bladder cancer
Schistosoma haematobium
Chemical notorious for causing urinary bladder cancer
Aniline dye
Chemical notorious for causing hemorrhagic cystitis
Toxin?
Cyclophosphamide/ ifosphamide
Toxin: acrolein
First urge to void is felt at a bladder volume of about?
150 mL
Marked fullness of bladder at about?
400 mL
Normal capacity of adult urinary bladder
500 mL
Rx for post-op urinary retention
Bethanecol
Parasympathetic effect = emptying
Effect of parasympathetic nervous system on the cardiovascular system
Inhibit
Substance secreted in response to changes in Bp by the JG cells of the afferent arteriole
Renin
Action of renin?
Converts angiotensinogen (from liver) to angiotensin I
Angiotensin I
vasodilator or vasoconstrictor?
Potent vasoconstrictor
Angiotensin II is a more potent vasoconstrictor than angiotensin I
Hormone that promotes WATER REABSORPTION in distal collecting ducts
Location?
Vasopressin/ ADH
Supraoptic nuclei of posterior pituitary gland
Drug used to treat bipolar disorder that causes nephrogenic Diabetes Insipidus
Lithium carbonate
Hormone produced by the adrenal cortex (z. Glomerulosa); promotes NA REABSORPTION in the collecting ducts
Aldosterone
Drug used to treat volume overload in liver cirrhosis of congestive heart failure which is an aldosterone antagonist
Spirinolactone
Side effect: gynecomastia and small balls
Produced by atrial cardiac cells and promote NA EXCRETION in the collecting ducts
Natriuretic peptides (NPs)
Action of parathyroid hormone
Phosphate EXcretion
Calcium reAbsorption
Vit D Production
Hormone that will decrease calcium
Calcitonin from C cells of thyroid
Thyroid cancer that is calcitonin producing
Medullary thyroid CA
(Bad prognosis)
Where is erythropoietin (EPO) produced
Peritubular capillaries of the kidney
Two erythropoietin Vit B
Vitamin B9 (folic acid) and B12 (cyanocobalamin)
Strict vegetarians
Vit B12 (cyanocobalamin)
Recently underwent a gastrectomy
Intrinsic factor deficiency
—-Removal of parietal cells
Promotes Calcium and Phosphate Absorption from the gut as a principal action
Vitamin D
1, 25 dihydroxycholecalciferol (active)
Enzyme present in kidney that converts Vit D to its active form
1 alpha hydroxylase
Case:
- infant
- hypogonadism
- syndactyly
- (-) 7 dehydrocholesterol reductase
Dx?
Smith Lemli Opitz Syndrome (SLOS)
Vitamin D deficiency in children
Rickets
Vitamin D deficiency in adults
Osteomalacia
High permeability of the Thin Descending limb to WATER is because of?
Aquaporin 1 channels
Specific action of ADH on the kidney
Causes insertion of aquaporin/ water channels on the distal tubules
Where is aldosterone produced specifically?
Zona glomerulosa of adrenal cortex
Clearance of this substance is used to estimate renal blood flow and renal plasma flow
Para aminohipuric acid (PAH)
Clearance of this substance is used to estimate GFR
Inulin
Renal threshold for glucose
180 ml/dL
3 urinary buffers
NaHCO3 - sodium bicarbonate
NaHPO4 - sodium phosphate
NH4 - ammonium
Most important ECF buffer
Bicarbonate buffers
Most powerful buffer because pK of proteins (amino acids)
Protein buffer
Causes of normal anion gap metabolic acidosis (NAGMA)
Diarrhea or
Renal tubular acidosis
“USEDCAR”
Ureteral diversion
Saline infusion
Exogenous acid
Diarrhea
Carbonic anhydrase inhibitors
Adrenal insufficiency
Renal tubular acidosis
Carbonic anhydrase inhibitor that is used to treat glaucoma, hydrocephalus and acute mountain sickness
Acetazolamide
Cofactor for carbonic anhydrase
Zinc
Mammary myoepithelial cells are contractile epithelial cells that express _____________________
Smooth muscle a-actin (ACTA2)
The primary function of mammary myoepithelial cells is to contract in response to _________ release by posterior pituitary gland upon sucking of nipple
Oxytocin
Milk letdown reflex
Milk ejection reflex
Uterine contraction
Oxytocin
Specific part of hypothalamus that synthesizes oxytocin
Paraventricular or magnocellular nuclei
Galactorrhea causes
Nipple stimulation
Prolactinoma of anterior pituitary
Drugs (anti-psychotic, anti-depressant, digitalis, reserpine, estrogen, dopamine 2, methyldopa)
Pressure of the fluid in the pleural space; slightly negative
Pleural pressure
Major muscle of inspiration
Diaphragm
—-phrenic nerve
Air pressure inside alveoli
Alveolar pressure
Difference between alveolar and pleural pressure
Transpulmonary pressure
Measures lung DISTENSIBILITY
Compliance
“Compliant lungs are easy to distend”
Property of matter to resist DEFORMATION
Elastance
“Highly elastic structures are difficult to deform”
Compliance work is ____ in emphysema (obstructive) and ____ in lung fibrosis (restrictive)
Compliance work is INCREASED in emphysema and REDUCED in lung fibrosis
Obstructive lung diseases
- destruction of lung tissue and the loss of elastin and collagen
Emphysema
Asthma
Normal aging lung
Restrictive lung diseases
Pulmonary fibrosis
Alveolar edema
Atelectasis
Increased surface tension
Created by attractive forces between water molecules
Produces a collapsing pressure
Surface tension
Decreases alveolar surface tension to decrease the work of breathing
Surfactant
Collapsing pressure = 2(surface tension)/ alveolar radius
Law of laplace
ARDS in newborn due to
Prematurity
(-) surfactant
ARDS in adult due to
Sepsis/ infection
Diffuse Alveolar Damage (DAD)
Air Flow Resistance = (air viscosity)(airway length)/ airway radius
Poiseuille’s Equation
Volume inspired or expired with each normal breath
Tidal volume
500ml
Extra volume that can be Inspired over and above the tidal volume
Inspiratory Reserve Volume (IRV)
3000ml
Maximum extra volume that can be Expired by forceful expiration after the end of a normal tidal expiration
Expiratory Reserve Volume (ERV)
1100ml
Volume that Remains in the lungs after maximal expiration
Residual Volume (RV)
1200ml
TV + IRV = ?
Inspiratory Capacity
TV + IRV = IC
500 + 3000 = 3500ml
ERV + RV = ?
Functional Residual Volume (FRV)
1100 + 1200 = 2300 ml
TV + IRV + ERV =
Vital Capacity (VC)
500 + 3000 + 1100 = 4600ml
TV + IRV + ERV + RV =
Total Lung Capacity (TLC)
500 + 3000 + 1100 + 1200 = 5800ml
Lung Volumes
___ in RESTRICTIVE
___ in OBSTRUCTIVE
DECREASE in RESTRICTIVE disease
INCREASE in OBSTRUCTIVE disease
Total Lung Capacity
___ in RESTRICTIVE
___ in OBSTRUCTIVE
DECREASED in RESTRICTIVE
INCREASED in OBSTRUCTIVE
Maximum amount of air that can be exhaled in 1 sec after a maximal inspiration
Forced Expiratory Volume (FEV1)
FEV1/FVC Ratio
___ in RESTRICTIVE
___ in OBSTRUCTIVE
0.8
Normal or increased in RESTRICTIVE
Decreased in OBSTRUCTIVE
Reversibility is demonstrated….
12% and 200ml increase in FEV1 15mins after an inhaled Beta 2 agonist
Or
2-4 week trial of oral corticosteroids (OCS) (Prednisolone or Prednisone 30-40mg daily)
Portions of the lungs that are VENTILATED but in which NO GAS EXCHANGE occurs
Pulmonary Dead Space
Volume of conducting airways NOT involved in gas exchange
(Approx. 150ml)
Anatomic dead space
Ventilated alveoli that are NOT PERFUSED
Negligible amount
Alveolar dead space
SUM of anatomic and alveolar dead spaces
Physiologic dead space
Increases anatomic dead space
Mechanical ventilator (extra tubes)
Respiratory centers of the brain
Pons and Medulla
Controls basic RHYTHM of respiration
Dorsal Respiratory Group of Medulla
Stimulates EXPIRATORY MUSCLES as in forced expiration
Ventral Respiratory Group of Medulla
INHIBITS INSPIRATION thus decreasing lung filling and increases respiratory rate
Pneumotaxic of Pons
INCREASES DURATION of inspiration thus increases lung filling and decreases respiratory rate
Apneustic of Pons
Lung overinflation stimulates stretch receptors and transmits signal through vagus nerve to the Dorsal Respiratory Group switching off inspiration
Tidal volume 3x normal (>1.5L)
Hering-Breuer Inflation Reflex
Lung overinflation stimulates the Dorsal Respiratory Group switching off inspiration
VT 3x normal (>1.5L)
Best oxygenated (ventilated) lung zone
Zone 1 - apices
No blood flow during cardiac cycle
Best perfused lung zone
Zone 3 - bases
Continues with cardiac cycle
Maximum amount of O2 that can combine with Hemoglobin of the blood
1g Hgb + 1.34ml of O2
Major form of CO2 in the blood
Bicarbonate
Phenomenon where bicarbonate ions diffuse from RBC into plasma and chloride ions diffuse into RBC to take their place
Chloride shift
Phenomenon associated with unloading of carbon dioxide secondary to increased OXYGEN
Haldane effect
Phenomenon associted with unloading of oxygen secondary to increased H+
Bohr effect
Major forms of CO2 transported as..
Bicarbonate (*)
Carbaminohemoglobin
Dissolved CO2
Nerve supply for the anterior 2/3 of the tongue
CN 7 - facial nerve
Diseases that presents ectopia lentis (2)
Marfans
Homocystinuria
Transparent and avascular part of the eye
Only human tissue that can be transplanted without fear of rejection
Cornea
Findings of cornea with wilsons disease?
Tx?
Keyser fleischer rings
Penicillamine
Layer of the retina converts 11-cis retinal to all-trans retinal
Pigment epithelial cells
- to absorb stray light and prevent scatter of light
Vitamin necessary for the regeneration of 11-cis retinal
Vitamin A
Earliest manifestation: Nyctalopia (night blindness)
Allow dim light vision and peripheral vision
Rods or cones?
Rods
Area of the retina which only has cones
Fovea centralis
Day vision
High visual aCuity
Color vision
Will adapt first
Rods or cones?
Cones
Unit of measure of the refractive power of a lens
Diopters
Normal and correct focus
Normal vision
Emmetropia
Farsighted
Light focus BEHIND retina
CONVEX lens correction
Hyperopia
Nearsighted
Light focus in FRONT of retina
BiCONCAVE LENS
Myopia
Curvature of lens not uniform
CYLINDRICAL LENS
Astigmatism
Condition with increase intraocular pressure?
Gold standard to diagnose?
Rx?
Glaucoma
Tonometry
Acetazolamide, timolol, pilocarpine, bimatoprost
Mast cell stabilizer used in a form of eyedrops
For conjunctivitis
Ketotifen
Loss of accomodation power of lens (aging)
CONCAVE LENS
Presbyopia
Pie in the sky lesion
Meyer’s loop
If cut, will result to homonymous hemianopia with macular sparing
Geniculocalcarine tract
Free nerve ending
Pain
Cold
Warmth
Pacinian corpuscles
Pressure
Meissner’s corpuscles
Touch
Muscle Spindle
Stretch
Golgi tendon receptor
Tension
Simultaneous neuronal discharge
Summation
Summation by activating multiple terminals on widely-spaced areas
Spatial
Rapidly successive discharges from a single presynaptic terminal
Increasing the frequency of nerve impulse in each fiber
Temporal
Occurs when membrane potential is NEARER TO TRESHOLD FOR FIRING than normal but is not yet at the firing level
Facilitation
Potential that OPPOSES MOVEMENT of an ion
Nernst potential
Receptor: pain and temperature
Free nerve ending
Receptor: light touch
Merkel’s tactile disks
Receptor: fine touch
Meissner corpuscles
Receptor: Pressure and vibration
Pacinian corpuscles
Receptor: cold temp
Krause’s corpuscles
Receptor: warm temp
Ruffini’s endings
Receptor: muscle Tension
Golgi Tendon organs
Receptor: muscle Length
Muscle Spindle
Bending of light rays at angulated interface
Refraction
Ratio of velocity of light in air to the velocity in the substance
Refractive index
Optics of the eye (3)
Lens
Pupil
Retina
Emmetropia
Normal eye
Eyeball that is too short or lens too weak
Corrected with Concave lens
Hyperopia
Eyeball that is too long or lens that is too strong
Corrected by convex lens
Myopia
Refractive errorthat causes visual image one plane to focus at a different distance from that of the plane at right angles
Corrected with SPHERICAL LENS & CYLINDRICAL LENS
Astigmatism
The ability to determine distance of an object from the eye
Depth perception
Interneurons that help analyze visual signals before leaving the retina
Amacrine cells
Cell type for fine details and color vision
Parvocellular
Cell type for rapidly moving visual signals and low-contrast stimuli
Magnocellular
Area lack of rods and cones in the retina over the area of the optic disk 15°lateral to the central point of vision°
Blind spot
Rapid jerk-like “jumping” movement of the eyes to shift the focus on a visual scene
Saccades
Rapid smooth movement of the eye
Pursuit movement
Responsible for rapid head and eye turning movements
Superior colliculi
Refers to lack of fusion of the eyes
Strabismus
Total body water measurement
Antipyrine
Clearance of this substance used to estimate GFR
Inulin
Plasma or Intravascular volume measured
Evan’s blue dye
Most important ECF buffers
Bicarbonate buffer
Most powerful buffer because pK of proteins (amino acids)
Protein buffer
Clearance of substance is used to estimate Renal Blood Flow and Renal Plasma Flow
PAH / Paraaminohippuric
Highest % of glomerular filgrate reabsorption occurs in
Proximal tubules at brush border and microvilli
Filling nerve
Sympathetic nerve
Will cause emptying of bladder
Parasympathetic
Normal protein content of urine
0 (zero)
Usual daily urine output
720-1440mL
Bladder muscle responsible for urination
Detrussor muscle
Urinary buffers
Sodium bicarb (NaHCO3)
Sodium phosphate (NaHPO4)
Ammonium (NH4)
Cofactor of carbonic anhydrase
Zinc