Exam 3 BIOS 1310

Nasal Cavity

What are Nasal Conchae

• directs air into 6 passageways/meatuses (splits airstream to make it swirl)

• Functions: Warming, Better sense of smell, Traps particles

Pharynx (Throat)

What is Uvula

Produces thin mucus that lubricates pharnyx

Larynx contains what two main structures

• vocal cords; when they vibrate they produce sound

• Epiglottis; epiglottis, closes during swallowing (blocks food from going in airway)

Tracheal has what cartilage and other features

• C-shaped cartilages: hold open Trachea

• Mucous glands, and pseudostratified ciliated columnar epithelium

Difference between Lungs

• Right Lung: 3 lobes (sup, mid, inf lobe)

• Left Lung: 2 lobes (Apex and Base; cardiac notch)

What is the hilum

• Site of entrance and exit in lungs for blood vessels and bronchi

Bronchial Tree and the breakdown

• branching system of air tubes

• Trachea → Main bronchi (each lung) → Lobar Bronchi (each lobe) → Segmental bronchi (more branches) → Bronchioles → terminal bronchioles (smallest conducting) → respiratory bronchiole → alveolar duct → alveoli

Alveoli

• Site of exchange with many capillaries surrounding

Conducting Zone

• Trachea to terminal bronchioles

• Conducts the air and has no gas exchange

Respiratory Zone

• Respiratory bronchioles to alveoli

• Site of exchange

Where can you find Elastic Connective Tissue in respiratory system, made of? what does it do?

• Found in lungs and bronchi + bronchioles

• Contains elastin.fibers

• Stretches with inhalation and during elastic recoil (unstretched) it expels air

Where can you find overlapping plates/cartliage, made of what cartliage?

• NOT on main bronchi and bronchioles

• Found on all other bronchi

• contains hyaline cartliage

Smooth muscle found on Bronchioles does what?

• Controls diameter of airways and protects lung and body from inhaled irritants or toxins

What is a Bronchospasm

• When smooth muscle of bronchioles spasms/constricts, causes excess music

• Caused by asthma, allergies, chemical fumes

Alveoli cells contains what epithelium and cells

• Simple Squamous Epithelium

  • Squamous Alvelolar Cells—flat for gas exchange

    • “Type I pneumocytes”

  • Great Alveolar Cells—produces surfactant + not flat

    • “Type II pneumocytes”

What does surfactant do?

• Substance that reduces surface tension of liquid that that it is dissolved in

  • Prevents collapse of alveoli in lungs

What is comprised of Respiratory membrane, why is it very thin?

• Squamous alveolar cells + basement membrane + capillary endothelial cells

• Thin for gas diffusion

Alveolar Macrophages / Dust Cells

• Phagocytize of inhaled debris (stuff not trapped in mucus)

Inspiration is breathing ___ and Expiration is breathing out ___

in; out

Quiet Respiration

Involuntary, relaxed breathing

Forced Respiration

• Deep and rapid

  • Involuntary: exercise or coughing

  • Voluntary: yelling

Inspiration causes muscles to do what?

create vacuum inside lungs

Expiration causes….

increased pressure inside the lungs

What is the prime mover of respiration? Supplemental respiration?

Diaphragm; ribs and sternum and an pressure that increased abdominal pressure

Ventilators

Used in medicine as an external pressure to inflate lungs

• endotracheal tube connected to air pump

• Nasogastric tube for food

Composition of Ai

• 78% Nitrogen

• 20.9% of Oxygen

• 0.03% Carbon Dioxide

  • Argon and other gases ~1.07%

Equilibrium

Rate of dissolution = rate of release

Bicarbonate Buffering System…

Saturation is..?

• Max dissolved solute/solubility

  • Influenced by temp and pressure

Pressure is commonly measure as _______

mm Hg (MERCURY)

Dalton’s Law is used for…

• mixtures of gases

  • Total pressure = sum of pressures of individual gases

  • Partial pressure…part of gas that makes up a sum of gas

Dissolved Gas Gradient

How is O2 carried in blood

• Hemoglobin carries blood

  • Contains 4 hemes→each heme binds one O2

• 1.5% of O2 is dissolved in plasma

How is CO2 carried in blood

• 90% in form of H2COH2 and HCO

• 5% dissolved in plasma

• 5% binds to proteins

  • Carbamino compounds and Carbaminohemoglobin (HbCO2)

How does CO2 load in RBCs

• Carbonic anhydrase (enzyme)

  • CO2 + H2O ←> H2CO3

What does metabolism waste come from?

• Products of catabolism

  • Aerobic respiration: CO2 + H2O

  • AA Catabolism: CO2 + H2O + NH3

Where does Nitrogenous waste come from

• From breakdown of nitrogen-containing molecules

  • Creatine → Creatinine

  • Nucleic Acids (ex: guanine and adenine → uric acid)

  • Amino Acids

Uric Acid

• Breakdown of nucleic acids

• Can crystallize

  • Kidney stones, gout

Renal Calculi? What are they and What do they come from?

• Kidney Stones (many kinds)

• Crystallization of:

  • Calcium oxalate

  • Calcium Phosphate

  • Uric acid

    • From: not enough water or too much meat

  • Cysteine

    • amino acids and cystinuria (genetic disorder)

What happens during the process of excretion?

• eliminating waste from body

Kidney Functions

• Filters blood (excretes waste, hormones, foreign substances)

• Regulates: Blood Volume, BP, Osmolarity and Electrolyte band acid-base a balance

• Endocrine

  • Erythropoietin _> RBC production

  • Calcitriol → Calcium homeostasis

  • Renin → Increase BP

• Gbuconeogensis in starvation

Anatomy of Urinary System

Kidney Anatomy

Nephrons are?

• tubular

• Functional unit of kidney

  • Filtration of blood

  • Reabsorption of nutrients

  • Excretion of waste

Collecting Tudor’s in nephrons

• Several collecting ducts merge into papillary duct

• 6 nephrons ave. Per duct

Path of Urine Drainage

Renal Circulation

Nephron Structure

What is Nephron Loop

• aka Loop of Henle

• Thick and thin descending limbs

• Thick and thin ascending limbs

Renal Tubule

• PCT + nephron loop + DCT + collecting duct

  • Not renal corpuscle

Glomerulus

• Little ball of capillaries inside capsule

  • No venules

  • Afferent Diameter is large then efferent

What is Renal Corpuscles

• Glomerulus + glomerular capsule

  • Where blood is filtered

What is the Glomerular Capsule

• Bowman’s capsule

• Epithelium

  • 2 connected layers

    • Space in between

  • Parietal layer (simple squamous)

  • Visceral layer (podocytes)

Podocytes

• Special epithelial cells

• Surrounds glomerular

What are pedicels?

• Found on podocytes

  • Tiny extensions that interdigitate; in between are slits for filtration

Cortical Nephrons

• 85% of nephrons

• Short

• Most of nephron found in cortex

Juxtamedullary Nephrons

• Nephron is need in medulla

  • Deeper and longer than cortical

• Concentration urine

  • Water retention

Cortical Nephrons Circulation

• Efferent arterials → plexus of vessels

• Peritubular capillaries

  • Surround PCT and DCT

Juxtamedullary Nephron Circulation

• Efferent arterials → capillaries around nephron loop

  • Vasa recta

Glomerular Filtration

• bulk movement of fluid (includes cells, proteins, glucose, AAs, ETC.)

Tubular Reasborption

• “good stuff” taken back into blood

  • AAs, Vitamins, glucose, electrolytes

Tubular Secretion

• Transport stuff from blood into tubular fluid

  • Uric acid, H+, drugs

Water conservation (How much do we filtrate, and urinate)

• Filtration: 180 L/day

• Urine: 1-2L/day

  • 99% reabsorbed

Glomerular Filtration Membrane, found? Made up of what (3) pars?

• 3 parts

  • Fenestrated endothelium capillary

  • Basement membrane

  • Filtration slits

• Found surrounding glomerular capillaries

• Water and small solutes move from blood to capsular space; RBCs and big stuff stay back

What does Net Filtration pressure (NFP) do?

• Drives filtration out of glomerulus

• NFP = Blood hydrostatic pressure - Colloid Osmotic P - Capsular P

Glomerulus Blood Hydrostatic Pressure (BHP), how does pressure change across areas?

• Very high pressure: ~60mm Hg

  • In capillaries 10-30 mm Hg

  • No venule side → no reabsorption

• Afferent diameter » Efferent (big entrance small exit)

What is Colloid Osmotic Pressure

• Osmosis back into blood

  • Due to retained proteins

  • Stays costant

What is Capsular Pressure

• Filtrates 180L / day

  • Resistance of flow in tubule → pressure

What does Glomerular Filtration Rate (GRF) influence?

• Too fast → not enough reabsorpion

  • Loss of water and electrolytes, etc.

• Too slow → wastes reabsorbed

What 2 ways is Glomerular Filtration Rate controlled?

• Myogenic mechanism

• Tubuloglomerular feedback

  • Both control glomerular blood pressue

Myogenic Mechanism

A rapid response where smooth muscle in the afferent arteriole contracts due to increased stretch from higher blood pressure.

• Stabilization of GFR despite systemic BP fluctuations

Tubuloglomerular Feedback

A slower mechanism that involves macula densa cells detecting high NaCl concentration, leading to vasoconstriction of the afferent arteriole to decrease GFR.

What 3 parts make up the Juxtaglomerular Apparatus?

The juxtaglomerular apparatus consists of the macula densa, granular cells, and extraglomerular mesangial cells.

What is Macula Densa?

• A patch of sensory cells

  • Part of ascending lab epithelium

  • Sense levels of NaCl in tubular fluid

What does GFR causes to raise in asc, limb? What does Macula Densa secrete due to this?

• GRF too high results in increased NaCL in asc, limb (causing not enough reasborption)

• In response Macula Densa secretes ATP

Extraglomerular Messangial Cells do what with ATP?

• Converts ATP to adenosine (paracrine signal gland to granular cells)

Granular Cells (Juxataglomerular cells) are?

• Special smooth muscle cells (wraps around Afferent arteriole

  • Adenosine signal causes constriction in afferent

Renin-Angiotensin-Aldosterone Mechanism is part of, and functions to?

• Part of hormone system and baroreflex

• Function to raise blood pressure of whole body (systemic)

Angiotensinogen is …? from?

• Precusor protein with no activity from liver

  • Plasma globulin

What is Renin?

• Enzyme that activates hormone system

• Secreted by granular cells (into blood)

• From kidney due to drop in BP

What is ACE / Angiotensin-Converting Enzyme?

• Enzyme from lung endothelial cells that cleaves off Ang-I…forming Angiotensin II te active hormone that increases BP

Renin Angiotensin-Aldosterone Mechanism Full Process, 5 area where Ang-II goes:

1. Angiotensinogen is cleaved of 10 AAs by Renin

2. Angiotensin I is formed from the 10 AAs

3. ACE cleaves 2 AAs from Ang-I

4. 8 AA structure forms Ang-II (The leftover 2 AAs are recycled)

5. Ang-II goes to

• blood vessels smooth muscle for vasoconstriction (increase in BP)

• Ang-II can also go to Adrenal cortex of kidney, which causes release of aldosterone, thus causing Na and water retention (BP increase)

• Ang-II can go to proximal convoluted tubule (PCT) for Na+ absorption

• Ang-II can go to hypothalamus for thirst→drinking causes increase in BP

• Ang-II can go to Posterior pituitary to secrete ADH→water retention

What is ACE2?

• Inactivates Ang-II, receptor for Cortana virus and other diseases

ACE Inhibitors do what?

• Drugs that reduce BP, thus cancelling ACE Turing Ang-I to Ang-II

Proximal Convoluted Tubule histology (PCT) consists of?

• Simple cuboidal epithelium

  • Many micro ills = brush border

    • (More surface area = more absorption)

  • Lots of mitochondria

Renal Tubule Histology consists of?

• Depending limb is thick

• Simple squamous, thin (simple diffusion)

• Ascending limb is thick

• DCT

  • Simple cuboidal with few microvilli

PCT Reabsorption, what is absorbed and how often?

• From filtrate, PCT absorbs:

  • ~65% of water and electrolytes

  • ~100% of “good stuff”

    • Glucose

    • AAs

    • Vitamins

    • Etc.

• Constant reabsorption, mostly not regulated by hormones

What are the different PCT Reabsorption Routes?

• Transcellular Route

  • Active transport (Primary and secondary)

  • Passive transport

• Paracellular Route

  • Movement through tight junctions, selectively leaky (allows some stuff to go through)

  • Passive transport

What gradients drive PCT reabsorption?

• Na+ / K+ pumps

• Colloid osmotic pressure (after glomerular filtration, high protein conc.)

What is Solvent Drag in PCT Reabsorption

• Solutes carried by movement of solvent

  • H2O + everything dissolved in it

• Reabsorption into blood

Explain Transcellular Route movement of Glucose in PCT

• Glucose

  • Into cell: secondary active transport

  • Out of the cell: facilitated diffusion (via carrier proteins)

Explain H+ movement in Trancellular Route in PCT

• H+ ions out

  • Antiporter

  • Acid-base balance

Explain Cl- reabsorption in Trancellular Route in PCT

• Cl- reabsorbed

  • Secondary transport

How does water move in the transcellular Route in PCT

• Water

  • Passives: osmosis

  • Aquaporins—channel proteins

What is the Transport Maximum (Tm), what is glucose example

• Max reabsorption capacity

• Glucosuria

  • High Blood Sugar Level → excess glucose passed in urine

What does osmolarity measure?

Total booked of all solutes / L

• Plasma is .3 osm

How does Osmolarity Gradient change from cortex to medulla

• Tissue fluid osmolarity increases with depth in the medulla

What is the collecting duct’

• Permeable to water

• Impermeable to solutes

• Concentrates urine