A&P Exam 3 Flashcards
How does Boyle’s Law relate to pulmonary ventilation?
Gasses fill containers
If it is a large volume→ molecules don’t hit each other, so there is low pressure
If small area → molecules will hit wall and each other often = high pressure
P1V1=P2V2
What happens during quiet inspiration?
Inspiration → enlarge thoracic cavity
Decreases pressure (less than atmospheric) → air moves in
What Muscles are used in inspiration?
-Flattens diarphragm= increase height of the thoracic cavity
-External intercoatals= lift ribs and sternum= greater diameter by a few m
-Decreases pressure by 1mmHg=500ml
What Happens during deep inspiration?
-7x= 3500ml
-Mucles:
Accessory muscles →scalenes, …→ scalenes erect spine
What happens during normal expiration?
-Muscles engaged in inspiration relax= causes passive recoil
-Decreases thoracic cavity volume→ decreases volume→ increase pressure by 1mmHg
What Happens During Forced Exhale?
-Oblique and transverse abs–>Force abdominal organs against the diaphragm
-Internal Intercostals–>Depress rib cage further
-Both of these decrease thoracic volume which increases pulmonary pressure
Cough
-deep breath, close glottis, force air out, open glottis, air rushes out
Laugh/cry
inspiration and several short expirations
Sneeze
cough through your nose
hiccups
diaphragm spasms
Yawn
deep inspiration, jaw opens, ventilates alveoli
Airway Resistance
-flow= change and pressure over resistance
-Resistance–>medium bronchi
-Flow stops at terminal bronchial b/c diffusion takes over
Alveolar Surface Tension
-Water molecules are polar, so they are attracted to each other= surface tension
-This attraction by itself would collapse alveoli
-Surfactant= lipid protein detergent →Type 2 alveolar cells→ decrease water cohesion
Homeostatic Imbalance in Surfactant
-Premature infants born with respiratory distress
-Alveoli/ lungs collapse
-Treatment is artificial surfactant
Lung compliance
-Healthy lungs are compliant and stretchy more the lungs expand w/ an increase in transpulmonary pressure= more compliance
Homeostatic Imbalance in Lung compliance
-Inflammation
-Scarring or decrease surfactant
-Less compliant
-Makes it hard to breath
Tidal volume
-500ml
-amount of air exchanged in normal quiet inhale
Inspiratory reserve volume
-the amount of air that may be inspired after a tidal inspiration
-1,900-3,100 mL
Expiratory reserve volume
-amount of air that may be expired after a tidal respiration
-700-1,200mL
Residual volume
-the amount of air in the lungs after maximal expiration
-1,100-1,200mL
Inspiratory capacity
TV+IRV
Amount of air a person can maximally inspire after tidal volume
2,400-3,600
Functional residual capacity
-amount of air left in lungs after tidal expiration
-ERV+RV
-1,800-2,400
Vital capacity
-total amount of exchangeable air in and out of the lungs
-3,100-4,800mL
-TV+IRV+ERV
Total lung capacity
-total amount of exchangeable and non exchangeable air in the lungs
-TV+IRV+ERV+RV
Dalton’s Law
Total Pressure= sum of partial pressure
Dalton Law w/ Air
Air= 760 mmHg (100%)
-79 % nitrogen=597 mm Hg
-21% Oxygen=159 mm HG
-0.04% CO2=0.3 mmHg
-0.5% H2O=3.7 mmHg
Henry’s Law
-Gas will dissolve in liquid in portion to partial pressure
-How much also depends on gas solubility and temperature
Example of Henry’s Law with Air
-CO2 most soluble
-O2 1/20th as soluble
-N2=Poorly Soluble
What is the respiratory membrane?
Alveoli= 300x 10^6
Most of the lung column is alveoli= a lot of surface area for gas exchange
3 Types of Alveoli Cells
1.Type 1
2.Type 2
3.Alveolar macrophages
Type 1 Alveolar Cells
Alveolar cells
Flimsy basement membrane
Pulmonary capillary endothelium
Respiratory membrane 0.5 micron
Type 2 Alveolar Cells
-Make surfactant
-Make surface tension
Alveolar Macrophages
-Dust cells= sweep what we don’t want
-Keep things sterile
-Swept up by cilia
-At a rate of 2 million cells an hour we swallow what is swept up
External respiration
-co2 in blood→air
-deoxyhemoglobin(O2=40and CO2=45 and gets swapped) encounters
pulmonary gas exchange and becomes oxyhemoglobin (O2=100 and CO2=40)
-driven by pressure
Internal respiration
-gas exchange that occurs with tissues
-blood has O2=100 and CO2=40 and tissue has O2-40 and CO2=45
-O2 enters and Co2 leaves tissue
Cellular respiration
6o2+C6H12O6→6H2O+6CO2+ATP(E) +Heat
Factors that Influence Gas Exchange
1.Partial Pressure and solubility of gas
-O2 gradient larger, but still reaches equilibrium in ¼ a second
-Co2 gradient is small and is 20x more soluble
-Need stable Co2 for blood pH
2.Thickness of respiratory membrane
-Can increase b/c of scaring
3.Ventilation-perfusion coupling
-Match Ventilation to blood flow in pulmonary capillaries
-If O2 is low= pulmonary capillary constriticion which moves blood to respiratory areas where O2 is high
-If O2 is high = dilation
-If Co2 is high =bronchial dilation
What percent of blood is dissolved and what percent is not?
1.5% is dissolved= poorly soluble
98.5% Hb bound= oxyhemoglobin= HbO2
Describe how oxygen binding changes Hb shape and affinity
-1 molecule of hemoglobin carries 4 O2 molecules
-First O2 binds to Hb→ Hb changes shape→ greater affinity for O2
-Makes it easier to bind 3 other O2
-4 O2=saturated
What Decreases Hemoglobin saturation?
Greater temp
Lower pH
Greater Co2
What increases Hb saturation?
-Less temp
-Lower pH
-Lower CO2
-Metabolically active tissue
Briefly describe the right shift vs left shift of the O2-Hb dissociation curve
Right shift in Curve=
-Increase saturation
-Weakens Hb and O2 bond which decresaes affinity
Bohr Effect:
A. Lower pH & increase Co2= more O2 release
B.Exercise= need more O2 for muscles
-Increase blood flow
-O2 is unloading at the muscle
-Decrease Hb affinity(attraction) to O2
HI in Oxygen Saturation
1.Hypoxia-Inadequate O2 Delivery
2.Cyanosis-Hb saturation is less than 75%
3.Carbon Monoxide Poisoning
-Hb has high affinity for Co2
-After 1 hr of pure O2, but Co levels will only drop by 50%
3 ways CO2 is transported
1.Plasma
2. Hemoglobin
3. Bicarbonate
How much Co2 is Transported in Plasma
20%=pCO2
How much of the body’s Co2 is in hemoglobin and how does it bind to it?
-20%–>CO2Hb=carbaminohemoglobin
-Bind to globin not heme but decreases affinity (more O2 released)
-In lungs → O2 “kicks off” Co2
How much CO2 is carried by bicarbonate and how is it carried in bicarbonate?
-70%
-Steps
1.Co2 enters RBC with water
2. + Carbonic Anyhydrase=H2Co3
-Carbonic acid
-unstable/ dissociates
3. →H + HCO3(bicarbonate)
4.Bicarbonate goes into plasma and chloride shift occurs causing cl-
ions to enter counteracting the trreease of an Ions
4.The H binds to hemoglobin causing the Bohr Effect= release O2 into tissue
and cells
How is ventilation controlled?
1.Control of pH by ventilatory Rate
2.Neural Control
how does pH control ventilation?
-Co2 increase in blood= slow shallow breaths= decrease pH and more carbonic acid
-Decrease co2 in blood= rapid and deep breathing= increase pH
How do Neural Controls Effect Ventilation?
High brain centers
1. Hypthalymus: pain and emotion
Cerebral Cortex: voluntary
2. Medulla: Inspiratory Center
Starts and stops inspiration
pacemaker= 12- 16 breath per minute
Sends impulses to the diaphragm via phrenic nerve
Sends impulses to incercoastal muscles via intercostal nerves
3. Pons
Smooths out the breathing rhy
What factors influence Respiratory Rate?
1.Chemoreceptors
2.Mechanoreceptors
How do Chemoreceptors influence respiratory rate?
-In aortic arch, brain, and muscles
1.Arterial CO2
Increase Co2= lower pH= increase respiration
pCo2>23Hg= hypercapnia
pCO2,37mmHg=Hypocapnia
decreasepCO2= increasepH= decrease Respiration
2.Arterial H+
decreasepH= increase respiratory rate
3.Arterial pO2
Less sensitive
<60mmHg
How do mechanoreceptors influence respiratory rate?
-Irritant receptors and stretch
-Increases or decreases respiratory rate
Respiratory Tracts as an embryo
Development is cephalocaudal
Respiratory tract 4 weeks into development
Olfactory Placodes→Olfactory pits →Nose
Palate–>Cleft lip/ palate occurs at this time
Respiratory Tract at 28 weeks of development
Can breath
No surfactant
Breath→ amiontic fluid, vascular shunts bypass lungs
Respiratory tract at birth
Respiratory rate= 60/min
Respiratory tract post birth in life
-5 years= 25/min
-adult=12/min
Age:
1. Increases respiratory rate, loss or elasticity, nose dry, mucus thicker
2.Decrease in ciliary activity = increase infections
3.Sluggish macrophages
Kidney Location
Located behind the the peritoneal cavity →retroperitoneal
Right kidney is lower than the left
Renal fascia and perirenal fat capsule support and hold it in place
Kidney Structure
- Capsul
-Fibrous
-Protects and encloses - Cortex
-Outer layer
-Collecting ducts and nephrons are located here - Medulla
-Interior from cortex
-Contains pyramids
-Where urine is made
-Has renal papilla on it’s central end and drains into the minor calyx
-Minor Calyx drains into major calyx → renal pelvis to
Ureter→renal bladder
Kidney Functions
-Processes blood
-Goes through entire blood plasma a day
blood= 1,200ml/min →120ml/min filterate=180L/day in filterate, but 99% is
reabsorbed= 1.5 L of urine left over
What do nephrons make
filterate
Parts of nephron
Renal Corpuscle has glomerulus
→proximal convoluted tubule→nephron loop→distal convoluted tubule→
nephron collecting duct
2 Types of Nephrones
Cortical
Juxtamedullary
juxtaglomerular complex structure
Blood comes in through the afferent arterial
Blood exists through the efferent arteriole
b/w the arterioles there and ascending limb of nephron connected by macula densa
Granular cells are on the outside of arterioles
What does the macula densa of the juxtaglomerular complex do?
Monitor sodium concentration
Chemoreceptors
What is occurring if the filtrate has a high sodium chloride content?
-Filtrate is being made to fast
-macula Densa Releases chemicals to constrict afferent arteriole
What is occurring if the filtrate has a drop in sodium chloride content?
Filtrate is being made to slow
Dilate arterioles and stimulate granular cells
What do the Granular Cells of the juxtaglomerular complex do?
-Mechanoreceptors
-SM muscle cells contain granules filled w/ renin
-Function as type of baroreceptor and regulate BP
What happens with granular cells if there is a drop in BP?
-Slows flow
-These cells release Renin→ increases BP
-BP can increase this with increased SNS causing renin release
Main Steps of Urine Formation
1.Glomerular Filtration
2.Tubular Reabsorption
3.Tubular Secretion
What does glomerular filtration do and where is it located?
-In renal corpuscle
- Ensures filtrate is with out cells or protein with it’s filtration membrane
What are the components of the filtration membrane and their functions?
- Fenesterated epithelium
- Stop large cells from entering filtrate - Basement membrane
-Restrict proteins, negatively charged repels proteins
3.Foot process of podocytes
-Filtration slits that further block protein
What is in filtrate and capillaries?
-Filter H2O, glucose, amino acids, urea, salts
-leave in capillary: proteins (COP), WBC, RBC
How does hydrostatic pressure effect filtration in glomerular filtration?
-pushes blood through the filteration membrane to make filterate
-Pushes out water and solutes
-blood=55mmHg
-Capsule hydrostatic pressure=15mmHg
How does Colloid Osmotic Pressure effect filtration in glomerular filtration?
-Protein in blood sucks fluid out of capsule
-blood = 30mmHg
What is the net filtration pressure in glomerular filtration?
55-(30+15)=10mmHg out
What is tubular reabsorption?
-Reclaim what body wants to keep
Ex. glucose, water, amino acids, ect.
-What is left makes urine→ unneeded substances (excess salt, excess water, waste)
How do lipid molecules move in the proximal convoluted tubule in tubular reabsorption?
Diffuses through the membrane → urea
Makes it hard to excrete lipid soluble drugs and pollutants
How do sodium molecules move in the proximal convoluted tubule in tubular reabsorption?
-Actively pumped out of tubules through cells via sodium potassium atpase pump
-Diffuses into capillaries
-Makes and osmotic gradient →H2O follow through aquaporins
-Creates an electrochemical gradient
-Sodium and HCO3 follow passively
How does carriers of glucose and amino acids move in the proximal convoluted tubule in tubular reabsorption?
-Use energy of concentration gradient
(secondary active transport)
-Max→excess into urine
1. T Max of glucose= 375 mg/min
2. Plasma glucose>190 mg/dl→ “spill
What happens after absorption in proximal convoluted tubule?
-65% of Nacl and water
-Nearly all K+
-All glucose and amino acids
-Things left now lack carrier proteins and are lipid soluble
What occurs in the nephron
- Descending limb
-Water leaves and is reabsorbed - Ascending
-Sodium pumped out and reabsorbed
-No aquaporins
What do distal convoluted tubules do in tubular reabsorption?
- Principal cells-
-Few microvilli
-Deal w/ NaCl
2.Intercalated Discs-
-Many microvilli
-Deal w/ acids and bases
-Have 10% NaCl and 25% water left
-Urine adjusts to body’s needs using hormones
Antidiuretic Hormone
Released by posterior pituitary
Inserts aquaporins into principal cells
Releases if serum osmotic pressure osm >300 mOSM
Aldosterone
-Formed in adrenal cortex
-Decrease blood volume or increase potassium→release ADH→ Angiotension 2→Aldosterone
-Make more sodium/ potassium pumped into principal cells into distal convoluted tubule and and CD
-Keeps Na in the body, potassium in filtrate, water follows sodium
Atrial Naturetic peptide (ANP)
-Atrial cardiomyocytes release= increase BP and B. Vol which decreases renin=
-Decrease aldesterone= decrease= excrete excess NaCl and H2O
Parathyroid Hormone
Reabsorbs calcium in DCT
steps of urine formation
1.glomerular filtration
2. Tubular Reabsorption
3. Tubular Secretion
Tubular Secretion: Where does this take place? What is secreted into the filtrate?
-Fine tune body’s chemical balance
-Selected waste added
-PCT and some DCt and CD
-Disposes of unwanted things not already in filterate
-Organic acid and base pump
-Ammonia, catecholamines, bile salts
-Sulfuric and phosphoric acid, uric acid
-Eliminate undesirable things that were reabsorb= uric acid and urea
-Rids body of excess K
-Controls blood pH
-Decrease pH=excess H, retains HCO3
-Increase in pH= retain cl instead of HCO3
Explain how hydration and dehydration regulate urine volume and concentration
When dehydrated= increase urine concentration
When hydrated= increase urine dilution
Define osmolality
-Osm
-1 mole of paticles/1kg H20=milliosmoles=0.001 Osm
What happens in the nephron loop?
-Thin simple squamous epithelium, variable permeability
-Allows hypotonic filterate to form
-Descending
-Has aquaporins so is permeable to water not NaCl
-Water moves out osmotalitly and sodium chloride stays
-Concentration is 300- 1200 mOSM
-Ascending
-Pumps Nacl pumps out Nacl out, water is blocked
-Creates osmotic gradient in interstitial fluid of the medulla
Distal Convoluted Tubule Sodium and Water %
Have 10% NaCl and 25% water left
Urine adjusts to body’s needs using hormones
Cells of the distal convoluted tubule and what they do
1.Principal cells-
-Few microvilli
-Deal w/ NaCl
2.Intercalated Discs-
-Many microvilli
-Deal w/ acids and bases
What hormones affect reabsorption?
Antidiuretic Hormone
Aldosterone
Atrial Naturetic peptide (ANP)
Parathyroid Hormone
Antidiuretic Hormone
-Released by posterior pituitary
-Inserts aquaporins into principal cells
-Releases if serum osmotic pressure osm >300 mOSM
Aldosterone
-Formed in adrenal cortex
-Decrease blood volume or increase potassium →release ADH→ Angiotension 2→ Aldosterone
-Make more sodium/ potassium pumped into principal cells into distal convoluted tubule and CD
Keeps Na in the body, potassium in filtrate, water follows sodium
Atrial Naturetic peptide (ANP)
-Atrial cardiomyocytes
-release= increase BP and B. Vol which decreases renin=Decrease aldesterone= decrease= excrete excess NaCl and H2O
Parathyroid Hormone
Reabsorbs calcium in DCT
Tubular Secretion
-Fine tune body’s chemical balance
-Selected waste added
-PCT and some DCt and CD
-Disposes of unwanted things not already in filterate
-Organic acid and base pump
-Ammonia, catecholamines, bile salts
Sulfuric and phosphoric acid, uric acid
-Eliminate undesirable things that were reabsorb= uric acid and urea
-Rids body of excess K
-Controls blood pH
-Decrease pH=excess H, retains HCO3
-Increase in pH= retain cl instead of HCO3
Define osmolality
Saltiness of the medulla
1 mole of paticles/1kg H20=milliosmoles=0.001 Osm
What happens in the nephron loop?
-Thin simple squamous epithelium, variable permeability
-Allows hypotonic filterate to form
What occurs in the descending nephron loop?
-Has aquaporins so is permeable to water not NaCl
-Water moves out b/c of the external osmolality and sodium chloride stays
-Concentration is 300 at start and 1200 mOSM at bottom o f the loop
How is micturition controlled?
- Blader fills 200mL
-Stretch receptors–>PSNS tells brain –> I need to pee
-Spinal reflex → detrusor m. contract internal
urethra sphincter relaxes
2.If Brain says Hold, Bladder relaxes and waits for next 200mL
3.Void
-Pons increases PSNS
-Relaxes urethral sphincter
-At 600ml= you will go
4.Residual Volume= 10ml
Incontinence
-Stress on pelvic floor (stretches) from:
Overfilled bladder
Childbirth
Surgery
Urinary retention (after anesthesia)
Enlarged prostate
Newborn to 18mths Micturition
New=Can’t concentrate urine= void 5-40 times/day
1-2mths= 400mL per day
15months= know void
18 months=
-Hold urine x2 hours
-Control of external uretheral sphincter
4 year old micturition
night lack of control
Adult Micturition
Void 1500mL per day
Micturition as we age
Decrease in kidney function b/c decrease in nephron #
Drop by 50% at age 80
Drop of bladder capacity by 50% at 80
Incontinence and nocturia
what occurs in the ascending limb of the nephron loop?
1.Pumps Nacl pumps out Nacl and 2Cl out, water is blocked
-NaCL =cotransport
2. K is pumped out
-Creates positive charge on membrane
-Mg and Chloride both positive ions leach out of membrane in places where the positive potassium is not present=Paracellular transport
What does the medullary gradient need to be
-salty
-can be wiped out if really overhydrated
Overhydration Causes what?
1.Decrease of osmollality of extracellular fluids
2.Decreases ADH from posterior pituitary
3.Decreases the number of aquaporins in collecting duct
4.Decreases water reabsorption from the collecting duct
5.Creates a large volume of diffuse urine
What does Dehydration do?
Increases osmolality in extracellular fluid
Increases ADH release from posterior pituitary
Increases number of aquaporins
Increase H2O reabsorption
Makes small volume of concentrated urine
What % of pee is solute?
95% water/ 5% solutes
What causes different colors of urine?
yellow= urochrome from breakdown of hemoglobin
pink/brown= beets and stuff
cloudy= infection
What causes urine odor?
Odor= bacteria breakdown of bacteria
Urine pH
pH 4.5-8
t causes a fruity urine odor?
fruity=diabetes
What is specific gravity?
-Ratio of density of urine to distilled water
-Increases with increased solute
What is the specific gravity of water and urine?
Water= 1
urine=1.001-1.035
3 Types of Kidneys that form as embryos
Pronephros
Mesonephros
Metanephros
Pronephros
4-6wks
Form degenerate
Pronephric duct stay
Mesonephros
2nd-3rd month
Pronephric duct → mesonephric duct
Male= ductus deferens
Female= disappears
Function until final kidney development
Amniotic fluid= urine produced starting 3 months
Metanephros
Wk 5
Uretic bud from endoderm
Makes ureter, renal pelvis, and collecting ducts
Metanephric bud b/cms nephrons
Kidneys ascend to final position
HI in Kidney development
-horseshoe kidney
-can live fine with it
Lipid Soluble Hormones
aka Steroids
Made from cholesterol
Made by gonads and adrenal
Can go through the pa=lasma membrane
Made to order
Long-half life in blood (days)
Need to be metabolized by the liver
Water Soluble Hormones
-Amino acid Based
Can’t cross plasma membrane
Can be stored in gland
Most hormones
Aka proteinaceous
Bits of peptide or protein
Modified amino acids→ thyroid, epinephrine, or norepinephrine
Short half life in blood (mins)–> removed by the kidneys
How do hormones act?
-Hormones effect cells w/ specific receptor= target cells
-Effect is to increase or decrease activity of cells
What do hormones effect one attached to receptor?
1.alter plasma membrane permeability by opening/ closing ion channels
2. Stimulate synthesis of enzyme and protein
3.Activate or deactivate enzyme
4.Induce secretion of exocrine or endocrine glands
5. Stimulate mitosis
How do Proteinaceous hormones bind to receptors?
-Water soluble
-Do not need a carrier
-Bind to plasma membrane receptors= G protein coupled receptors which activate 2nd messenger (cAMP)–>trigger a preprogrammed response in cell
How do Lipid Soluble hormones bind to receptors?
Need a carrier in blood
Bind to intracellular receptor
Directly activate genes
Hormones are a negative or positive feedback loop?
negative
3 stimuli that control the release of hormones
- Humoral Stimulation
-Ions= K and Ca
-Nutrients= Glucose, amino acide
2.Neural Stimulation
-SNS→ adrenal medulla→epi and norepinephrine
3.Hormonal Stimulation
-Tropic hormones cause hormone release
-Glands may respond to mmore than 1 hormone
Permissiveness with hormones
A Must be there for B to have effect
Synergism with Hormones
-A has effect
-B has effect
-A+B increases effects
Antagonism with Hormones
A opposes the effects of B
The medullary osmotic gradient is determined by the permeability properties of the what?
nephron loop
Renin is released by granular cells in the afferent arterioles when what occurs?
macula densa cells detect low NaCl levels
Where in the nephron loop does a filtrate become hypotonic?
ascending limb
Oxygen moving into the tissue and CO2 moving into the blood from the tissues is caused by what?
diffusion
The part of the nephron that makes a filtrate hypertonic?
descending limb
What does the macula densa do if it senses to much NaCl in the filtrate in the ascending limb of the nephron loop
constrict afferent arterioles
What is when oxygen moves into blood and CO2 moves out?
External respiration
What occurs with the glomerulus during dramatic blood loss?
filtration rate will go down
WHat kind of blood pressure is regulated by the kidneys?
-long term
What is always negative to prevent lung collapse?
Interpleural Pressure
When oxygen binds to Hb, how does shape change?
changes to increase affinity to oxygen until Hb is all filled up
what is the most important factor in respiratory rate?
pCO2
What is the least important factor in air flow?
resistance
after sodium is reabsorbed it creates what 2 gradients?
-active as water follows salt
-passive as anions follow passively
What keeps the trachea from collapsing
1.Catilaginous rings
2.Trachealis muscle
Intrapleural pressure is typically what?
-negative
Oxygen and CO2 are exchanged in the lungs via what?
diffusion
What pressure works to collapse the lungs?
-surface tension of the alveolar fluid
Types of pressure in the renal corpuscle
Hydrostic and colloid
How to calculate net filtration?
H-C=NF
