Renal anatomy, physiology and urine formation Flashcards by Alexander DuMars

What are the four main components of the urinary system?

kidneys, ureters, bladder, urethra

How well did you know this?

Not at all

Perfectly

What three hormones do the kidneys produce?

erythropoietin
calcitriol
prostaglandins

How well did you know this?

Not at all

Perfectly

at what vertebral level is the left kidney located?

T11-L2

How well did you know this?

Not at all

Perfectly

At what vertebral level is the right kidney located?

T12-L3

How well did you know this?

Not at all

Perfectly

What is the covering on the kidney?

Capsule

How well did you know this?

Not at all

Perfectly

List the 7 parts of the internal kidney

Cortex (w/ renal columns)
medulla (pyramids)
minor and major calyces
renal pelvis

How well did you know this?

Not at all

Perfectly

What are the 5 layers of the adrenal gland? exterior to interior

Capsule, zona glomerulosa, zona fasiciculata, zona reticularis, adrenal medula

How well did you know this?

Not at all

Perfectly

What is the main functional unit of the kidney?

Nephron

How well did you know this?

Not at all

Perfectly

Where are nephrons located?

Renal cortex and medulla

How well did you know this?

Not at all

Perfectly

What are the 4 components of the nephron?

glomerulus, proximal convoluted tubule, loop of henle, distal convoluted tubule

How well did you know this?

Not at all

Perfectly

Which part of the nephron is considered the “medullary portion”?

Loop of Henle

How well did you know this?

Not at all

Perfectly

In what order of structures do fluids leave the nephron collecting ducts to head toward the bladder?

minor calyx, major calyx, renal pelvis, ureter

How well did you know this?

Not at all

Perfectly

What are the two types of nephrons and what is the difference?

Cortical - mostly in the renal cortex, have short loop of Henle

juxtamedullary - nephrons extend deep into the medulla, have long loop of Henle

How well did you know this?

Not at all

Perfectly

Define filtration

substances pulled from blood into kidney

How well did you know this?

Not at all

Perfectly

define reabsorption

substances pulled from kidney back into the body

How well did you know this?

Not at all

Perfectly

define secretion

substances pulled straight from the body to the kidney (prox. and distal conv. tubules, loop of Henle)

How well did you know this?

Not at all

Perfectly

define excretion

urine leaves kidney via collecting duct, calyces and renal pelvis

How well did you know this?

Not at all

Perfectly

What percentage of blood leaving the left ventricle of the heart enters the kidnes via the renal arteries?

20-25%

How well did you know this?

Not at all

Perfectly

How much blood goes through the kidneys per minute?

~1200 ml/min (both)

~600 ml/min (each)

How well did you know this?

Not at all

Perfectly

Where do the kidney’s afferent arterioles travel to?

to the capillary tuft (glomerulus)

How well did you know this?

Not at all

Perfectly

Where did the blood come from that is in the kidney’s efferent arterioles?

Blood that was not filtered by the glomerulus (capillary tuft)

How well did you know this?

Not at all

Perfectly

Where do the kidney’s efferent arterioles travel to?

from glomerulus they become the peritubular capillaries in the cortex then the vasa recta in the medulla

How well did you know this?

Not at all

Perfectly

what is the (outer) parietal layer of the bowman’s capsule made of?

fenestrated squamous epithelium (aka parietal epithelial cells)

How well did you know this?

Not at all

Perfectly

What is the (inner) visceral layer of the bowman’s capsule made of?

podocytes (aka visceral epithelial cells)

How well did you know this?

Not at all

Perfectly

3 layers of the glomerular capillary wall

fenestrated endothelium basal lamina podocites

What is GFR stand for?

glomerular filtration rate

What is GFR?

90-120 ml/min

What is the name of the GFR test?

clearance test

What does the clearance test test for?

how well the kidneys are filtering creatinine

What are "threshold substances"? 4 examples

substances that are almost completely reabsorbed by renal tubules (when concentration is w/in normal limits) - amino acids - creatine - potassium - sodium chloride

Which part of the loop of Henle is water permeable?

descending loop of henle

Where does reabsorption of solutes occur in the loop of henle?

ascending loop of henle

how much of the glomerular filtrate is reabsorbed by the time it reaches the distal tubule?

~90%

where is urea reabsorbed?

the collecting duct

What two things does tubular secretion account for?

1) The removal of waste substances that weren't filtered by the glomerulus (toxins and meds like penicillin) 2) secretion and removal of hydrogen and other ions to regulate acid-base and electrolyte balance

What it the pH range of the body?

7.35 to 7.45

What organs regulate the body's pH?

Lungs and kidneys

Are bicarbonates secreted or reabsorbed?

Both! Can be secreted but are often reabsorbed (up to 100%) depending on the pH of the body

What are the 3 main functions of the distal and collecting tubules?

1) adjustment of pH, osmolality and electrolytes 2) secretion of K+, ammonia and H+ 3) reabsorption of Na++ and bicarbonate

What microscopic structure in the kidney regulates the function of each nephron?

Juxtaglomerular Apparatus (JGA)

What are the 3 components of the JGA?

1) macula densa of distal convoluted tubule 2) juxtaglomerular cells (produce and secrete renin) 3) mesangial cells (secretion of erythropoietin)

What precursor does renin react with? What does renin convert?

precursor: angiotensinogen | converts to angiotensin 1

What enzyme converts angiotensin 1 to angiotensin 2? Where?

angiotensin converting enzyme (ACE) | lungs

What does angiotensin 2 cause?

systemic vasoconstriction

what two hormones does angiotensin 2 trigger the release of in order to cause vasoconstriction?

1) aldosterone - adrenals, increases Na absorption | 2) antidiuretic hormone aka vasopressin - posterior pituitary

from where is aldosterone secreted?

adrenal cortex

What are two functions of aldosterone?

1) + blo NA reabsorption leading to + blo volume (water follows salt) 2) enhances K/Na ions in distal tubules

What layers make up the adrenal cortex?

Zona glomerulosa, zona fasciulata, zona reticularis

aka for ADH

vasopressin

Where is ADH/vasopressin synthesized?

hypothalamus

Where is ADH/vasopressin stored?

posterior pituitary gland

aka posterior pituitary

neurohopophysis

aka anterior pituitary

hypophysis

what are two functions of ADH/vasopressin?

Makes walls of collecting ducts permeable, regulates H2O absorption in collecting ducts

What is a result of insufficient ADH?

diabetes insipidus

what are signs of DI?

polydipsia, polyphagia, polyuria

What are the two causes of DI?

1) decreased production of ADH/vasopressin | 2) abnormal kidney response to ADH/vasopressin

What does SIADH stand for?

Syndrome of Inappropriate ADH secretion

What is SIADH?

excessive secretion of ADH when not needed

What is the most common cause of SIADH? what percentage?

small cell lung carcinoma 80%

urine excretion rate

~1 ml/min

urine excretion when dehydrated

~0.3ml/min

urine excretion when excessively hydrated

~15ml/min

average daily urine volume adult

1200-1500 ml

When is the most urine produced?

daytime

word to describe decrease urinary volume during shock or acute glomerulonephritis (<400ml/24 hr period)

oliguria

word to describe complete suppression of urine formation (<75 ml/24 hr period for 2-3 days)

anuria

in 24 hours, how many grams of dissolved material is secreted in urine? How much is urea?

~60g | 1/2 is urea

6 things that are abnormal in urine (BBGKPP)

``` bilirubin blood glucose ketone bodies porphyrins protein ```

3 C's of urine sediment

Cells Crystals Casts

define cystitis

inflammation of bladder

define nephritis

inflammation of the kidney

nephritis with bacterial infection

pyelonephritis

nephritis without infection

glomerulonephritis