Anatomy & Physiology: Chapter 26 & 27

Ptosis

"floating kidney" "nephroptosis" the kidney slips inferiorly due to not being adequately supported. Most common in thin people, can cause the ureter to kink eventually causing tissue damage to the kidney.

What is the sequence of flow from the kidneys to the urethra?

1. Glomerulus 2. Capsular space 3. PCT 4. Loop of Hence 5. DCT 6. Collecting Duct 7. Papillary Duct 8. Minor Calyx 9. Major Calyx 10. Renal Pelvis 11. Ureter 12. Urinary Bladder 13. Urethra 14. External Urethra Orifice

What are the functions of the kidney? (4)

1. Regulate blood volume and composition, 2. Regulate pH, blood pressure, and glucose levels 3. produce hormones calcitriol and erythropoietin 4. Excrete waste

sequence of blood flow from renal artery out to the capillaries

1. Renal Arteries ... divide into 2. Segmental Arteries ... divide into 3. Interlobar Arteries ... pass through 4. Renal Columns ... then to 5. Arcuate Arteries ... the into 6. Cortical Radiate Arteries ... divide into 7. Afferent Arterioles ... split into capillaries called 8. Glomerulus to efferent arteriole to peritubular caps

What are the regions of the kidney and subcomponents?

1. Renal Cortex - outer edge, dived into the outer cortical zone and an inner juxtamedullary zone 2. Renal Medulla - inner portion, 10-18 renal pyramids (base facing out), renal papilla pointing in and the renal columns between pyramids 3. Renal Pelvis - minor and major calyces and sinus

Layers of the kidney

1. Renal Fascia - thin layer of dense connective tissue that anchors the kidney to its surroundings 2. Adipose Capsule - fatty layer that protects the kidney from trauma 3. Renal Capsule - smooth, transparent sheet of dense connective tissue that gives shape

What percent of the filtrate is reclaimed?

10%

How much filtrate is reclaimed in the DCT/collecting ducts?

10-15%

Papillae

10-18, points inwards

Pyramids

10-18, the base faces outwards

What is the bicarbonate reserve?

16 bicarbonate ions to every 1 carbonic acid

How much is reabsorbed in the PCT overall?

70%

What is the myogenic mechanism?

A pressure induced vasoconstriction/vasodilation depending on the pressure

What does the amino group act as?

A weak base

Which hormones control water balance and how?

ADH - inserts water channels into cell membranes allowing for water reabsorption Aldosterone - promotes reabsorption of Na+, causing water reabsorption ANP - promotes natriuresis, increases loss of water in urine

Know what ADH, Aldosterone, ANP, and Renin do well: What do they target? What do they cause to happen to target?

ADH targets collecting ducts and DCT and causes conservation of water which raises water volume, ANP causes sodium natriuresis which lowers BP and blood volume, aldosterone causes absorption of sodium and water and pushes potassium, renin is released from JG cells and initiates the renin angiotensin pathway we studied earlier.

What is acidosis? Alkalosis?

Acidosis - blood pH is below 7.35 Alkalosis - blood pH is above 7.45

How does the respiratory system compensate for changing pH levels?

Adjusts breathing

What vessel feeds the glomerulus and what drains it?

Afferent feeds, efferent drains

What hormones increase filtration (by retaining water or conserving sodium) and which one lowers blood pressure by causing sodium natriuresis.

Aldosterone increases filtration by retaining water or conserving sodium...also cause K secretion Atrial natriuretic peptide lowers blood pressure by causing sodium natriuresis (excretion of sodium in the urine)

What are symptoms of metabolic acidosis? What can cause it...list 3

Arterial blood levels of HCO3- falls Symptoms - rapid short breathes, confusion, fatigue, headache, sleepiness, jaundice, little hunger

What are symptoms of metabolic alkalosis? What can cause it?

Arterial blood levels of HCO3- rises Symptoms - confusion, hand tremor, muscle twitching, nausea, spasms

What is the ascending limb permeable to? The descending limb?

Ascending limb is permeable to ions and impermeable to water Descending limb is permeable to water

What is the most important extracellular/blood buffer?

Bicarbonate

What are symptoms (what would be blood levels for Pco2, and bicarbonate) of respiratory acidosis? What can cause it?

Blood pH drops due to excessive retention of CO2 (from airflow block, impaired respiratory drive) Symptoms - headache, confusion, anxiety, drowsiness and stupor

What are symptoms of respiratory alkalosis? What can cause it?

Blood pH rises due to excessive loss of CO2 as in hyperventilation (from hyper-breathing) Symptoms - dizziness, bloating, lightheadedness, dry mouth, arm tingling, numbness, chest discomfort

What is the main intracellular cation? Anion?

Cation - Potassium Anion - Chloride... no proteins/phosphate

What is the main extracellular cation? Anion?

Cation - Sodium Anion - Chloride

What sized molecules are filtered, and which are not?

Everything smaller than midsized proteins get filtered

How does the kidney compensate for changing pH levels?

Excrete H+ or conserve bicarb

What is the filtration membrane made up of? Which layer has fenestrations, which has podocytes with pedicels?

Filtration Membrane 1. Endothelium that lines the glomerular capillaries - has fenestrations 2. Glomerular basement membrane - 3. Podocytes visceral layer of glomerular capsule

What is the GFR? How much is that a day?

Glomerular filtration rate - 125ml/min which is 180 l/day

What is the Bowman's capsule another name for?

Glomerulus

What is the significance of the glomerulus and peritubular capillaries?

Glomerulus - where blood filtration starts Peritubular Capillaries - reunite to become the cortical radiate veins, then arcuate veins, then interlobar veins, and then into the left and right renal veins, allow reabsorptions and secretion between blood and nephron

What is the renal corpuscle made of?

Glomerulus and glom capsule

What is the driving force for filtration?

Hydrostatic or blood pressure

Know well the percentage of fluid in the ICF vs ECF

ICF - 66% ECF - 33%

What occurs if water intake exceeds output? What if water loss is greater than intake? What

If intake exceeds output hypotonic hydration or water intoxication If loss is greater than intake, then dehydration occurs leading to increased thirst

JG cell of afferent arteriole and the macula densa cells of the distal convoluted tubule

Juxtaglomerular cells are mainly in the walls of the afferent arteriole (feeds the glomerulus). Macula densa cells line distal convoluted tubule and is the thickening where the tubule touches the glomerulus

What are the cells, what type are they and what do they produce if known in juxtaglomerular feedback?

Juxtaglomerular cells produce/store renin and are smooth muscle cells found in the afferent arteriole and they raise blood pressure and are baroreceptors The macula densa cells are of the DCT and are osmoreceptors that release an unknown chemical that influences the glomerulus

How does the nervous system regulates filtration?

Mainly through sympathetic nerves to vessels

Which sex is urogenital, which urinary only? How many urethra do you have?

Males are urogenital Females are urinary only One urethra in each gender

How much of the organic molecules?

Nearly 100%

In a normal kidney should glucose ever be secreted as waste?

No because a normal kidney should be able to reabsorb all of it

What is normal blood pH? What does the pH scale measure? What are the three lines of defense against fluctuations in pH? Define and acid and base

Normal pH is 7.35-7.45 pH measures how acidic or basic a substance is Lines of defense - buffer systems, exhalation of carbon dioxide, kidney excretion of H+ Acid - pH less than 7 Base - pH greater than 7

What hormones control calcium levels?

Parathyroid hormone and calcitriol raise, calcitonin lowers

What is the most import urinary system buffer?

Phosphate

Know the percentage of ECF that is plasma and the percentage of the ECF that is interstitial fluid

Plasma is 20% Interstitial fluid is 80%

What is the pelvis and what are the minor and major calyces?

Renal papilla project into minor calyces which from major calyces which funnel into the renal pelvis (urine collects in the renal pelvis and then heads out of the kidney through the ureter

Name 4 secreted substances by the nephron. Where does this occur?

Secretes K ions, hydrogen ions, xenobiotics, creatine. Occurs in the proximal tubule section

What is too much and not enough of each of the following called? Sodium, potassium, calcium...

Sodium - too much is hypernatremia, not enough is hyponatremia Potassium - too much is hyperkalemia, not enough is hypokalemia Calcium - too much is hypercalcemia, not enough is hypocalcemia

What hormones control sodium and potassium?

Sodium controlled by aldosterone, ADH, and ANP Potassium controlled by aldosterone

What controls filtration?

The force of hydrostatic pressure in the glomerulus

What is the most important intracellular buffer?

The protein buffer system

What happens to molecules if they exceed their transport maximum?

The tubules cannot reabsorb it all so the excess is passed through the urine. That solute will be found in the urine.

What about the carboxylic acid?

The weak acid would release protons when pH begins to rise

Which would donate protons when pH rises?

The weak acid... carbonic acid

Which molecule would accept protons when pH drops?

The weak base... bicarb

Know PSP/PAH tests for integrity of nephron to secrete

These molecules are neither filtered nor reabsorbed....only secreted. So they test the ability of the nephron to do secretion

What is water of metabolism from?

This is from cellular respiration in the ETS system where oxygen is the final electron acceptor and forms water

Fishberg test is for specific gravity and test the nephron ability to reabsorb

This tests the nephrons ability to reabsorb water. Done in the morning after no drink the night before...kidney should produce a concentrated urine

Why would the kidney secrete H+ ions?

To lessen the acidity of the blood

Know lining epithelium of ureters and bladder, how many ureters do you have?

Ureter is lined with transitional epithelium capable of stretching Bladder is lined by traditional epithelium You have 2 ureters

What are the names of the various UTI'S? Of the kidney? The bladder? The urethra?

Urethritis - infection of the urethra Cystitis - infection of the bladder Pyelonephritis - infection of the kidneys

What are the forms of water gain? What are the forms of water loss?

Water gain - ingestion and metabolic synthesis Water loss - urination, perspiration, exhalation and in feces

Buffers: What does the weak acid do? What do weak bases do?

Weak acid - donates protons/ H+ ions when pH begins to go up Weak base - accepts protons/ H+ ions when pH begins to go down

When would you see it from the ECF to the ICF?

When someone has consumed a large volume of water

When would you see shifts of water from the ICF to the ECF?

When someone is sweating a lot or losing a lot of water from GI, or is getting a little dehydrated

Can water osmose between fluid compartments?

Yes - but when the extracellular fluid is isotonic to the cells of the body, they do not shrink or swell

What regions are the nephron located in?

cortex

Collecting Ducts

fluid passes through the ducts to reach the calyces and renal pelvis

Chloride

helps regulate osmotic pressure between compartments, forms HCl in the stomach

Potassium

involved in fluid volume, impulse conduction, muscle contraction, and regulating pH

Location of the kidney

just above waist between peritoneum and posterior wall of the abdomen

What are the organs of the urinary system?

kidneys, bladder, ureters, urethra

Columns

section of the renal cortex which extend down into the medulla, separating the renal pyramids from one another

Detrusor Muscle

smooth muscle in walls of the bladder, remains relaxed to store and contracts to release

trigone

smooth triangle region, sensitive to expansion and signals when bladder is full

Calcium

structural component of bones and teeth, used for blood coagulation, neurotransmitter release, muscle tone, and excitability of nerves and muscles

Rugae

there when empty, allows bladder to expand when filled

Reabsorption id movement of molecules from where to where

tubes to blood

Sodium

used for impulse transmission, muscle contraction, and electrolyte balance