ID the two kinds of nephrons. Where are each located and how are they different anatomically? Which one is more numerous ?

➢ Cortical nephrons—85% of nephrons; almost entirely in cortex
➢ Juxtamedullary nephrons
i. Long nephron loops deeply invade medulla
ii. Ascending limbs have thick and thin segments
iii. Important in production of concentrated urine

1. Juxtamedulliary- efferent arteriole to vasa recta

2. Cortical- efferent arteriole to peritubular capillaries

.(Juxtamedullary has longer loop of Henle than cortical. However, corticalare much more numerous.Cortical nephrons barely extend into the medulla. Juxtamedullary nephrons extend much further down into the medulla)

ID and name the function of the following urinary organs renal artery,

• Renal artery supplies blood to kidney. This blood is used for energy and metabolism of kidney cells and also is used for filtration of wasteful materials
• deliver one-fourth of the total cardiac output (about 1200 ml) to the kidneys each minute.

Name the location and function of the JG cells only in the Juxtaglomerular apparatus.

Jg cells tell when the blood pressure drops

-leads into the renal sinus
-where the ureter, renal blood vessels, and lymphatics, and nerves all join the kidney

What are the three major processes of urine formation, where do they occur in the nephron and what is going on i.e. where are substances moving during each of the three processes?

1. Filtration(glomarilous) strains toxins out.

2.Reabsorption (mostly in PCT ) body is taking something something out, under hormonal control-ADH, aldosterone), goes back into the body because it is something it needs to keep.(H2O-ADH) Na+ is absorbed.

3. Secretion- Body has too much and wants to get rid of sodium potassium water mostly in the DCT, can happen elsewhere but mostly in the DCT/ACT- then you get urine.

List the pathway of filtrate from the glomerilous until it reaches the collecting duct and forms urine

glomerular capsule (capsular filtrate) → PCT (tubular fluid) → nephron loop → DCT → collecting duct → papillary duct (urine) → minor calyx → major calyx → renal pelvis → ureter → urinary bladder → urethra.

What does a positive vs a negative NFP mean (net filtration pressure)

main point to know is that without blood pressure there is no NFP .

huge amounts of filtrate can be produced even with theusual modest NFP of 10 mm Hg. The opposite side of this“coin” is that a drop in glomerular pressure of only 18% stopsfiltration altogether.The GFR is directly proportionalto the NFP, so any change inany of the pressures acting at the filtration membrane changesboth the NFP and the GFR. In the absence of regulation, an in-crease in arterial (and glomerular) blood pressure in the kid-neys increases the GFR. As we shall see in the next sectionhowever, GFR is tightly regulated.Regulation of Glomerular Filtrati

What is a typical GFR (globular filtration rate)

125 min/ml

Name the parts of the nephron

Be able to ID and give function of the following parts of a nephron: glomerulus, Bowman’s capsule, proximal convoluted tubule, loop of Henle, distal convoluted tubule, collecting duct, afferent arteriole, efferent arteriole, peritubular capillary, vasa recta.

Function of; glomerilous

• filtration happens here filteres out toxins
• consists of 50 intertwined capillaries
• projects into the glomerular (Bowman's) capsule
• blood leaves the glomerulus in an efferent arteriole

Function of;bowmnan's capsule

Bowman's capsule (or the Bowman capsule, capsula glomeruli, or glomerular capsule) is a cup-like sac at the beginning of the tubular component of a nephron in the mammalian kidney that performs the first step in the filtration of blood to form urine. A glomerulus is enclosed in the sac.

Function of;PCT proximal convoluted tubule

• reabsorption of water, ions, and all organic matter
• cuboidal cells with abundant microvilli

Function of;Loop of Henle

Descending Limb of Loop of Henle

• further reabsorption of water
• squamous cells

Ascending Limb of Loop of Henle

• reabsorption of sodium and chloride ions
• low cuboidal cells

Function of;Distal Convluted tubule DCT

• secretion of ions, acids, drugs, and toxins
• variable reabsorption of water, sodium ions, and calcium ions
• cuboidal cells with few microvilli

Function of;collecting duct

collecting ducts, each of which receives filtrate frommany nephrons, run through the medullary pyramids and givethem their striped appearance. As the collecting ducts approachthe renal pelvis, they fuse together and deliver urine into the mi-nor calyces via papillae of the pyramids

Function of;afferent arteriole

The afferent arteriole carries blood from the renal artery into the glomerulus, where it divides to form a circulatory network. At the distal end of the glomerulus, the capillaries rejoin to form the efferent arteriole through which blood leaves the glomerulus.

Function of;efferent arteriole

The efferent arterioles are blood vessels that are part of the urinary tract of organisms. The efferent arterioles form from a convergence of the capillaries of the glomerulus. They play an important role in maintaining the glomerular filtration rate despite fluctuations in blood pressure. they are smaller in diameter than afferents thus create resistance.

Function of;peritubular capillary

The peritubular capillariesarise from the efferent arteriolesdraining the glomeruli. These capillaries cling closely to adja-cent renal tubules and empty into nearby venules. They are low-pressure, porous capillaries that readily absorb solutes andwater from the tubule cells as these substances are reclaimedfrom the filtrate

Function of;vasa recta

bundles of long straight vessels called vasa recta(vasah rektah; “straight ves-sels”) that extend deep into the medulla paralleling the longestloops of Henle. The thin-walled vasa recta play an importantrole in forming concentrated urine,

Name the location and function of the JG cells only in the Juxtaglomerular apparatus.

????? One per nephron
➢ Important in regulation of rate of filtrate formation and blood pressure
➢ Contains
i. Chemoreceptors; sense NaCl content of filtrate
ii. Mechanoreceptors; sense blood pressure in afferent arteriole

On what specific spot of the nephron do ADH and aldosterone work?

• turned on by renin
• reabsorbs water from filtrate
• mostly in PCT

What are the ascending and the descending loops of Henle permeable/impermeable to?

How does ADH affect urine concentration?

A hormone released from the pituitary gland that causes water reabsorption in the kidneys, thus concentrating the urine

What is a diuretic and name some examples

➢ Chemicals that enhance urinary output
i. ADH inhibitors, e.g., alcohol
ii. Na+ reabsorption inhibitors (and resultant H2O reabsorption), e.g., caffeine, drugs for hypertension or edema

How does alcohol affect ADH?

Inhibits body from absorbing ADH

What are abnormal ingredients in urine?

protein (albumen), wbc, rbc, glucose

What are the normal ingredients in urine?

urea, uric acid, na,k, nitrogenous waste,

What is the pathway of urine from the collecting ducts to the urethra?

collecting ducts, papillary ducts, minor calyx, major calyx, renal pelvis,ureter,bladder,urethra,urethral orifice

What is the anatomical term for urination?

XXVI. Micturition

➢Urination or voiding
➢Three simultaneous events must occur
i.Contraction of detrusor by ANS
ii.Opening of internal urethral sphincter by ANS
iii.Opening of external urethral sphincter by somatic nervous system
➢Reflexive urination (urination in infants)
➢Pontine control centers mature between ages 2 and 3

What kinds of muscles are found in the detrusor, internal urethral sphincter, and external urethral sphincter ?

The urethral sphincter is crucial for the maintenance of urinary continence [1,2]. The urethral sphincter refers to one of the following muscles [3]: 1) the internal urethral sphincter (IUS), which consists of smooth muscle and is continuous with the detrusor muscle and under involuntary control, and 2) the external urethral sphincter (EUS), which is made up of striated muscle and is under voluntary control.

What are the standard physical characeristics of urine?

color,odor,PH, specific gravity?

➢Color and transparency
i.Clear
ii.Cloudy may indicate urinary tract infection
iii.Pale to deep yellow from urochrome
iv.Pigment from hemoglobin breakdown; more concentrated urine → deeper color
v.Abnormal color (pink, brown, smoky)
vi.Food ingestion, bile pigments, blood, drugs
➢Odor
i.Slightly aromatic when fresh
ii.Develops ammonia odor upon standing as bacteria metabolize solutes
iii.May be altered by some drugs and vegetables
➢pH
i.Slightly acidic (~pH 6, with range of 4.5 to 8.0)
ii.Acidic diet (protein, whole wheat) → ↓ pH
iii.Alkaline diet (vegetarian), prolonged vomiting, or urinary tract infections → ↑pH

What is the anatomical term for urination?

XXVI. Micturition

➢Urination or voiding
➢Three simultaneous events must occur
i.Contraction of detrusor by ANS
ii.Opening of internal urethral sphincter by ANS
iii.Opening of external urethral sphincter by somatic nervous system
➢Reflexive urination (urination in infants)
➢Pontine control centers mature between ages 2 and 3

What kinds of muscles are found in the detrusor, internal urethral sphincter, and external urethral sphincter ?

The urethral sphincter is crucial for the maintenance of urinary continence [1,2]. The urethral sphincter refers to one of the following muscles [3]: 1) the internal urethral sphincter (IUS), which consists of smooth muscle and is continuous with the detrusor muscle and under involuntary control, and 2) the external urethral sphincter (EUS), which is made up of striated muscle and is under voluntary control.

How does sympathetic stimulation affect the detrusor, 2 sphincter muscles, and external urethral?

inhibits detrusor contraction, internal urethral sphincter closes,sometic reflex contracts external urethral sphincter, will not pee

How does parasympathetic stimulation affect the detrusor, 2 sphincter muscles, and external urethral?

excites the detrusor muscles, inhibits internal urethral sphincter, ok to pee

What is Hypocalcemia?
Possible causes?
Consequences?

1. Hypocalcemia is when calcium level in the blood is to low
2. Possible cause: burns, vit. D deficiency, renal rubular disease, renal failure.
3.Consequences: tingling of fingers, tremors, skeletal muscle cramps, tetany, convulsions, depressed excitablility of heart, osteomalacia, and fractures

What is Hypercalcemia?
Possible causes?
Consequences?

1. Hypercalcemia is when calcium level in the blood is to high.
2. Possible causes: hyperparathyroidism, excessive vit.D, prolonged mobility
3.Consequences: decreased neuromuscular excitability, cardiac arrhythmias, and arrest

What is Hypochloremia?
Possible causes?
Consequences?

1. Hypochloremia is when chlorine levels in the blood are to low.
2. Possible causes: Metabolic alkalosis(due to vomiting or ingesting to much alkaline substances)or aldosterone deficiency
3.Consequences: no direct clinical symptoms

What is Hyperchloremia?
Possible causes?
Consequences?

1. Hyperchloremia is when chlorine levels in the blood are to high
2. Possible causes: dehydration
3. Consequences: no direct clinical symptoms

What is Hypokalemia?
Possible cause?
Consequence?

1. Hypokalemia is when blood potassium level is to low.
2. Possible Causes: GI tract disturbances, starvation, diuretic therapy.
3. Consequences: Cardiac arrhythmias, muscle weakness

What is Hyperkalemia?
Possible cause?
Consequence?

1. Hyperkalemia is when blood potassium level is to high
2. Possible cause: renal failure, deficit of aldosterone
3. Consequences: Nausea, vomiting, diarrhea, Bradycardia, cardiac arrhythmias.

What is Hyponatremia?
Possible causes?
Consequesnce?

1.Hyponatremia is when sodium ion concentrate is plasma is below normal.
2.Possible Cause: solute loss or water retention
3. Consequences: Impacts nervous system, neurologic disfunction

What is Hypernatremia?
Possible Causes?
Consequences?

1. Hypernatremia is elevated sodium in the blood
2. Possible cause: could be because of dehydration
3. Concequence:Nervous system impact, thirst, dehydration leads to confusion and lethargy progressing to coma.