Physiology

• Bell Magende
• Boyle
• Charles
• Henry
• LaPlace
• Starling
• Hering Breuer

anterior spinal roots are MOTOR, posterior SENSORY

at constant temperature, a volume of gas varies inversely with pressure

At constant pressure, a volume of gas varies directly with absolute pressure

solubility of gas in a liquid is proportional to the pressure of the gas

ventricular pressure depends on muscular tension, size and shape of the heart

Cardiac output is directly proportional to diastolic filling

limits respiratory excursion via the vagus nerve

Carbon dioxide diffuses out of the cell and into the capillary where is is transported 3 ways:

1. dissolved carbon dioxide in the blood 7%

2. in combination with hemoglobin 23%

3. as bicarbonate ions (HCO3) 70%

formed when carbon dioxide enters the red blood cell and combines with water via CARBONIC ANHYDRASE to form CARBONIC ACID which dissociates into HYDROGEN AND HCO3 ions. the HCO3 diffuses out of the RBC into plasma while CL ions diffuse into the RBC (chloride shift)

• Carbonic Anhydrase --> CO2 + RBC = Carbonic Acid
• Carbonic Acid splits --> H + HCO3
• HCO3 out of RBC into Plasma
• Chloride into RBC

97% is carried by hemoglobin 20ml O2 per 100 ml of blood

• Krause
• Ruffini
• Meissner
• Pacinian
• Merkel's
• Free nerve endings

cold

hot

touch and pressure

touch

touch

pain

• Tidal volume (TV)
• Inspiratory reserve (IR)
• Expiratory reserve (ER)
• Residual volume (RV)
• Inspiratory capacity
• Functional residual capacity
• Vital capacity
• Total Lung volume

• normal breathing
• 500ml

3000ml

1100ml

1200ml

TV+IR= 3500ml

• TV=500ml
• IR=3000ml

ER+RV= 2300ml

• ER= 1100ml
• RV= 1200ml

IR+ER+TV=4600ml

• IR=3000ml
• ER=1100ml
• TV=500ml

5800ml

• Medulla oblongata
• Pons

Has inspiratory and expiatory control centers

APNEUSTIC center and PNEUMOTAXIC center. Limits the duration of inspiration, but increases respiratory rate.

Chemoreceptors in Medulla Oblongata excited by CO2 and H and peripheral chemoreceptors in the carotid and aortic bodies which are sensitive to PO2.

• increase in PCO2 and H
• decrease in PO2

• decrease in PCO2 and H
• increase in PO2

• (diabetes mellitus)
• Increase in ketone bodies, respiration stimulated (Kussmaul's breathing) causing a "blow off" of CO2 decreasing H concentration.

• (vomiting)
• H concentration decreased, respiration inhibited, caused increase in PCO2, increases blood H concentration.

causes RESPIRATORY ALKALOSIS: because decreased H concentration, low PCO2. Rebreathing expired air increased PCO2 returns blood Ph normal.

Low Ph of blood due to HYPOVENTILATION

Neurohypophysis. Neuroectoderm connected to the base of the brain via supraoptic hypophyseal tract

Vasopressin acts upon the kidney to reabsorb water in the collecting duct. Increases blood pressure. Decreased ADH produced POLYDYPSIA and POLYURIA seen in DIABETES INSIPIDUS.

Responsible for milk let down and uterine contractions during labor and after birth.

"Rathke's Pouch" Influenced by negative feedback or releasing factors produced in the hypothalamus.

• Somatotrophin: Stimulated by growth hormone releasing factor from the hypothalamus.
• GHRF: responsible for stimulating the release of growth hormone and the release of an inhibitory hormone called somatostatin--> decreased produces dwarfism, increase produces giantism.

Corticotropin: stimulates the adrenal gland

Thyrotropin: stimulates thyroid

• stimulates follicle in preparation for ovulation in females
• stimulates sperm production in males

• Responsible for ovulation in females
• Regulates testosterone production

Stimulates milk production post partum

melanocyte stimulating hormone

takes calcium out of blood and into bone. made by the parafollicular cells of the thyroid.

Major hormone from the thyroid to regulate metabolism

Chemically more active than thyroxine. important in maintaining basal metabolism

• Decreased thyroid hormones produce a cretin in children or myxedema in adults.
• Increase produces increased metabolic processes, increased sympathetics and may lead to Graves disease.

increases blood calcium, decreases reabsorption of phosphates

Takes calcium out of the bone and into the blood stream. Important in many enzyme reaction and for contraction of muscles. Decrease produces tetany or muscle twitches. Increase seen in Osteitis Fibrosa Cystica. Increase in the blood produce increases in the kidney.

• Zona Glomerulosa
• Zona Fasciculata
• Zona Reticularis

Aldosterone (salt)

Cortisol (sugar)

Androgen (sex)

A mineralcorticoids that reduces sodium excretion by the kidneys and increases potassium excretion

A glucocorticoids that controls metabolism of carbohydrates, fats and proteins.

Medulla is derived from neural crest cells. Secretes epinephrine and norepinephrine. Acts as postganglionic sympathetic nervous system

Epinephrine and norepinephrine both secreted in response to sympathetic stimulation

Made in hypothalamus to inhibit growth hormone. Made by delta cells of the pancrease to inhibit insulin and gulcagon in the pancrease, gastrin in the gastric mucosa, secretin in the intestinal mucosa and renin in the kidneys.

A peptide formed in the liver and other tissues which mediates the effects of growth hormone on cartilage

Produced by ovarian follicle after stimulation by FSH. Thickens the lining of the uterus in the proliferative phage of the menstrual cycle (1st stage).

Produced by the corpus luteum after ovulation. Increases thickness of the uterine lining to make it ready for implantation. Increases in (2nd stage) of the menstral cycle called Secretory stage. Also responsible for increase in body temperature called Thermogenic Hormone.

produced in intersitital cells of Leydig in testes

Secreted by the beta cells in response to glucose

Responsible for increasing blood sugar

Auerbach's plexus. in muscular layer of digestive tract for GI mobility

In the submucosa to promote secretions

Ptyalin

• Pepsinogen in the presence of HCL becomes pepsin.
• Rennin clots milk

Produce HCL and intrinsic factor

Helps with protein digestion

a hormone responsible for contraction of the gall bladder when fat is present.

stimulates the flow of pancreatic juice and decreases gastric motility

lipase, amylase, maltase

• activated by enterokinase in intestine
• Trypsin and chymotrypsin split protein

Pacemaker. Self excitatory to the internodal pathways to the AV node (delays impulse) the to the AV bundle (of His) to the Purkinje system which conducts the impulse to the ventricles.

atrial depolarization

ventricular depolarization (atrial repolarization)

ventricular repolarization

period of relaxation

produces contraction

closure of AV valves during isometric contraction

closure of the aortic and pulmonic valves during isometric relaxation at the beginning of diastole

the small downward deflection on the arterial pulse or pressure contour, immediately following the closure of the semilunar valves sometimes used as a marker for the end of systole or ejection period S-T

Cardiac output is directly proportional to diastolic filling

In the carotid and aortic arches, respond to changes in blood pressure

occurs in diastole

• A. aortic
• R. regurgitation
• M. mitral
• S. stenosis

• P. pulmonic
• R. regurgitation
• T. tricuspid
• S. stenosis

Calcium is stored in the Sarcoplasmic Reticulum. the calcium in the sarcoplasm is low, the ATP is attached to the myosin crossbridges (this prevents the combining of actin and myosin).

calcium to be released at the myoneural junction which causes ACETYLCHOLINE release to the T tubules

SARCOPLASMIC RETICULUM to release CALCIUM. CALCIUM activates MYOSIN. MYOSIN breaks ATP to ADP plus P.

CALCIUM binds with TROPOMYOSIN, TROPONIN leaving ACTIN free. ACTIN and MYOSIN combine. ACTINOMYOSIN reacts producing a contraction.

CHOLINESTERASE destroys ACETYLCHOLINE.

Calcium goes back to the sarcoplasmic reticulum and the myosin becomes inactivated.

• ADP goes back to ATP
• ATP binds once again with MYOSIN

Tropomyosin-troponin reattaches to actin and bridges separate to reform thus we have relaxation.

• Action Potential
• Passive transport
• Active transport
• Absolute Refactory Period
• Relative Refractory Period
• Rheobase
• Chronaxie

• Inside the cell is K+ and Mg++
• Outside the cell is Na+ and Cl-
• Stimulation increases membrane permeability to sodium

• Na+ goes into the cell by diffusion creating a change in electronegativity.
• K+ goes out of the cell
• Cl- goes into the cell
• Decrease membrane permeability to Na+, K and Cl

• Sodium goes out of the cell
• Potassium goes into the cell
• Repolarization occurs due to increased potassium conductance.
• Moves back to resting membrane potential.
• Resting membrane potential: muscle -90MV and neuron -70MV

When a second action potential can not be elicited

When a second action potential can be elicited, but must be greater stimulus than the first

minimum current strength for an action potential to occur

time needed using 2x the rheobase for excitation