Urinary System, Fluid, Electrolyte, & Acid-Base Homeostasis
Help!
|
|
||||
|---|---|---|---|---|---|
| Urinary system organization | 2 kidneys, 2 ureters, 1 urinary bladder, and 1 urethra
🗑
|
||||
| Location of kidneys | retroperitoneal between the last thoracic & L-3 vertebrae; right is slightly lower due to liver position
🗑
|
||||
| Renal capsule | transparent fibrous membrane continuous with ureter
🗑
|
||||
| Adipose capsule | fatty tissue for protection and anchoring
🗑
|
||||
| Renal fascia | thin dense, irregular connective tissue to anchor kidney to abdominal wall
🗑
|
||||
| Nephroptosis | floating kidney
🗑
|
||||
| Renal hilus | deep fissure on the concave border through which urether leaves kidney and blood, lymph, & nerve supply enters the kidney
🗑
|
||||
| Renal sinus | cavity within the kidney where hilus enters
🗑
|
||||
| Renal cortex | superficial "rind-like" region extending medially to form renal columns
🗑
|
||||
| Renal medulla | darker inner-most region containing 8-18 renal pyramids
🗑
|
||||
| Papillary ducts | drainage area for nephron collecting tubules
🗑
|
||||
| Renal pelvis | single large cavity receiving urine from major calyces
🗑
|
||||
| nerve supply for kidneys | innervated by nerves from the sympathetic division of the autonomic nervous system
🗑
|
||||
| blood supply for kidneys | abdominal aorta branches into the R&L renal arteries
receives 1200 mL blood/min
🗑
|
||||
| Nephron | functional unit of the kidney
1 million/kidney=85 miles
🗑
|
||||
| Renal corpuscle | lies in the renal cortex and is where plasma is filtered
composed of glomerulus & Bowman's capsule
🗑
|
||||
| Glomerulus | special capillary network between the afferent & efferent arterioles; basement membrane blocks passage of blood cells & large plasma proteins
🗑
|
||||
| Bowman's capsule | epithelial cup surrounding glomerulus that forms a 3-layered filtration membrane
🗑
|
||||
| Renal tubule | lies in the renal cortex and extends into medulla
🗑
|
||||
| Function of renal tubule | passageway for the filtrate from Bowman's capsule; composed of proximal convoluted tubule (PCT), loop of Henle (descending & ascending), and distal convuleted tubule (DCT)
🗑
|
||||
| PCT cells | cuboidal cells with microvilli for increased surface area for reabsorption & secretion
🗑
|
||||
| Descending loop cells | simple squamous cells for osmosis & diffusion
🗑
|
||||
| Thick ascending loop | contains macula densa cells
🗑
|
||||
| Macula densa cells | special cells where loop touches afferent arteriole; monitor Na+ & Cl- levels in filtrate (incoming material)
🗑
|
||||
| Juxtaglomerular(JG)cells | special muscle cells in afferent arteriole that can constrict to regulate renal bp
🗑
|
||||
| Juxtaglomerular apparatus (JGA) | Macula densa & JG cells
🗑
|
||||
| DCT cells | contain special principal cells that respond to hormones ADH & aldosterone to help balance fluid, electrolytes, & water level
🗑
|
||||
| What is the secondary capillary system that surrounds each nephron? | peritubular (vasa recta) capillaries
🗑
|
||||
| What are the two types of nephrons? | Cortical & Juxtamedullary
🗑
|
||||
| Cortical nephron | glomerulus lies in outer region of renal cortex; short loop of Henle (80-85%)
🗑
|
||||
| Juxtamedullry nephron | Loop goes deep into medulla for urine concentration/dilution (15-20%)
🗑
|
||||
| What are the three basic processes performed by the nephrons while producing urine? | Filtration, reabsorption, & secretion
🗑
|
||||
| Glomerular filtration | bloop pressure forces water & dissolved plasma components (filtrate) through glomerulus & Bowman's capsule
🗑
|
||||
| What is the amount of glomerular filtration? | 180 L (48 gal)=125 cc/min filtrate enters yet only 1-2 L excreted/day (60X/d)
🗑
|
||||
| Why does so much material enter tubule system? | Glomerular capillaries are very thin,contain many fenestrations (pores), and are covered with mesangial cells
Glomerular bp (hydrostatic pressure) forces fluid into Bowman's capsule
🗑
|
||||
| Tubular reabsorption | selective return of water & solutes to bloodstream; 99% of filtrates reabsorbed into secondary capillary bed (peritubular capillaries)
🗑
|
||||
| How does so much material get reabsorbed from the tubule system? | Plasma proteins DO NOT enter tubule system, their presence in the peritubular capillaries acts as a magnet to draw fluid back into bloodstream (oncotic pressure)
🗑
|
||||
| Tubular secretion | Movement of material from blood into filtrate
Takes place via the peritubular capillaries
Maintains plasma pH and for elimination of creatinine,NH3,H+,K+,Rx, misc
🗑
|
||||
| Urinary excretion | Final elimination of wastes, excess H2O, and electrolytes
=glomerular filtration+tubular secretion-tubular reabsorption
🗑
|
||||
| Renal Plasma Clearance | Blood nitrogen ->Kidneys ->Urine
🗑
|
||||
| Layers of glomerular filtration from inner to outer | Endothelial fenestration, Basal lamina, and Slit membrane
🗑
|
||||
| How is renal function measured? | Measured as glomerular filtration rate (GFR) and dependent on constant blood flow to kidney
🗑
|
||||
| GFR | averages 105-125 mL filtrate/min and maintained at this rate over a 80-180 mmHG bp range
🗑
|
||||
| How is renal regulation achieved? | Renal autoregulation
Neural regulation
Hormonal regualtion
🗑
|
||||
| Renal autoregulation | intrinsic process for short-term regulation
🗑
|
||||
| Neural regualtion | during high activity level or with hemorrhage, sympathetic system nerves promote renal arteriole constriction to shunt blood back to heart and decrease GFR
🗑
|
||||
| Hormonal regulation | multi-system process for long-term regulation
🗑
|
||||
| regulation of urine concentration | affected by hormone levels & countercurrent flow
🗑
|
||||
| countercurrent flow | descending loop fluid flows next to but in opposite direction of fluid in ascending loop
🗑
|
||||
| Caffeine | blocks Na+ reabsorption
🗑
|
||||
| Alcohol | blocks secretion of ADH
🗑
|
||||
| Lasix | blocks Na+ reabsorption at different points along the tubule (esp in Loop region)
🗑
|
||||
| Urinalysis | analysis of volume, physical, chemical & microscopic properties of urine
🗑
|
||||
| Blood urea nitrogen (BUN) | measures how much urea is in blood
increased urea=decreased GFR
🗑
|
||||
| Plasma creatinine | end product of skeletal muscle metabolism; produced at steady daily rate; almost completely removed from blood
increased plasma creatinine=decreased GFR
🗑
|
||||
| Ureters | transport urine from renal pelvis via peristalsis & gravity (1-5 waves/min)
🗑
|
||||
| rugae | folds in mucosal lining of bladder that allow for increased surface area (volume)
🗑
|
||||
| max capacity of bladder | 700-800 mL
🗑
|
||||
| internal urethral sphincter | the smooth muscle layer of bladder responsible for internal involuntary control
🗑
|
||||
| external urethral sphincter | the smooth muscle layer of the bladder responsible for external voluntary control
🗑
|
||||
| urination | control of micturition
🗑
|
||||
| incontinence | lack of urinary control
🗑
|
||||
| urethra | terminal passageway for urine
also duct for reproductive secretions in males
1.5 inches in females
6-8 inches in males
🗑
|
||||
| Total Body Water (TBW) | Body fluid/water and its dissolved solutes (electrolytes)
🗑
|
||||
| Average Total Body Water | Females=55%
Males=60%
🗑
|
||||
| Intracellular fluid (ICF) | fluid located within cells; 2/3 TBW
🗑
|
||||
| Extracellular fluid (ECF) | fluid NOT located within cells; 1/3 TBW
🗑
|
||||
| ECF has 3 distinct locations in body | <20% plasma(intravascular(IV))-within blood vessels
<80% interstitial(IF)-between cells
<5% misc specialized fluids (third spaces)
🗑
|
||||
| Movement of fluids is primarily driven by? | Osmosis
🗑
|
||||
| Osmosis | movement of water and small dissolved molecules across a semi-permeable barrier
🗑
|
||||
| Sources of body fluid (water) gain | Ingested water - 2300 mL/day
Metabolic water - 200 mL/day (krebs)
🗑
|
||||
| Sources of body fluid (water) loss | Kidney - 1500 mL/day via urine
Skin - 600 mL/day via evaporation & perspiration
Lungs - 300 mL/day via respiration
GI tract - 100 mL/day via feces; also menstrual losses
🗑
|
||||
| Electrolyte | Substance that forms ions when dissolved in water
🗑
|
||||
| Ion | Charged atom (cation+;anion-);conduct weak electrical current; ie Na+,K+,Cl-,H+,HCO3-
🗑
|
||||
| Nonelectrolyte | Substance that does not ionize when dissolved in water due to strong covalent bonds holding molecule together; ie glucose, urea, proteins
🗑
|
||||
| Functions of electrolytes | a.Regulate movement of water(osmosis) between body compartments
b.Help maintain acid-base balance
c.Function as cofactors for certain enzymes
d.Carry weak electrical current->action potential->neuromuscular activity
🗑
|
||||
| Functions of nonelectrolytes | a.Regulate movement of water between body compartments via oncotic pressure
b. Nutrients or waste products of cellular metabolism
🗑
|
||||
| milliequivalents/liter(mEq/L) | Relates charges carried by ions; important for maintaining neutrality of body fluids
🗑
|
||||
| milliosmoles/liter(mOsm/L) | relates total number of particles in a solution; important for determining if H2O will move in/out of compartment
🗑
|
||||
| Exchange of fluids between IF and ICF occurs | across cell membranes via osmosis
🗑
|
||||
| Exchange between plasma(IV) and IF occurs | across capillary walls via:
a.Vesicular transport
b.Diffusion
c.Filtration
d.Reabsorption
🗑
|
||||
| Osmotic pressure(OP) | concentration of electrolytes in fluid
🗑
|
||||
| Vesicular transport(transcytosis) | endo & exocytosis of large molecules
ie nutrients & hormones
🗑
|
||||
| Diffusion | direct movement across capillary walls based on concentration difference=osmotic pressure (OP)
🗑
|
||||
| Filtration(bulk flow) | movement from IV to IF driven by blood pressure=hydrostatic pressure(HP)
🗑
|
||||
| Reabsorption | movement of water from IF into IV driven by concentration of plasma nonelectrolytes=oncotic pressure(OCP)
🗑
|
||||
| Unequal movements of fluid across cell membranes or capillary walls can result in? | Edema
🗑
|
||||
| Edema | accumulation of fluid in IF due to decreased reabsorption into IV(plasma)
🗑
|
||||
| Ascites | Abdominal edema
🗑
|
||||
| What causes edema? | a.Increased Na+ intake->water retention=increased bp
b.decreased fluid output by kidney=increased bp
c.decreased circulation of fluid due to cardiac, blood, or lymph vessel problems
d.decreased plasma protein(albumin)->decreased OCP=decreased PULL of m
🗑
|
||||
| Acidity is determined by what? | H+
🗑
|
||||
| Alkalinity is determined by what? | OH-
🗑
|
||||
| ECF pH range | 7.35-7.45
🗑
|
||||
| Removal of excess H+(or OH-) occurs via what three mechanisms? | a.Buffer Systems
b.Respiration
c.Kidney Excretion
🗑
|
||||
| What are the three types of buffer systems? | a.protein buffers
b.phosphate buffers
c.carbonic acid-bicarbonate buffer
🗑
|
||||
| Which buffer system is the most important? | carbonic acid-bicarbonate buffer
🗑
|
||||
| Buffer systems | instantly, but temporarily bind excess H+ to remove it from ECF, but NOT body; buffer="sponge" that converts strong acids/bases into weak acids/bases
🗑
|
||||
| Phosphate buffer | found in ICF & kidney cells
🗑
|
||||
| Carbonic acid-bicarbonate buffer | found in plasma & kidney cells
🗑
|
||||
| Respiration | rapid adjustment of pH via exhalation of H2CO3=volatile acid
🗑
|
||||
| Kidney excretion | slow adjustment of pH via secretion of nonvolitile(fixed) acids into urine and reabsorption of HCO3- by kidney
🗑
|
||||
| Acidosis | blood pH <7.35
s/s-depression of CNS
🗑
|
||||
| Alkalosis | blood pH >7.45
s/s-overexcitability of CNS
🗑
|
||||
| Compensation | physiological response to acid-base imbalance that attempts to restore the body to homeostasis
🗑
|
||||
| How much TBW do infants have? | 75-90% (most is in ECF)
🗑
|
||||
| How much TBW do the elderly have? | 50%
🗑
|
||||
| Urine leaves the urinary bladder through the | Urethra
🗑
|
||||
| Which of the following structures are found in the renal cortex? | Distal convoluted tubules
🗑
|
||||
| Fenestrations are associated with the | Glomerulus
🗑
|
||||
| Urine contains | Waste products of metabolism
🗑
|
||||
| The renal pelvis | Drains into the ureter
🗑
|
||||
| The kidneys help control blood pressure by the secretion of | Renin
🗑
|
||||
| Sodium is moved out of the cells of the proximal convoluted tubule and into the interstitial fluid by the process of | Active transport
🗑
|
||||
| The outer layer of the three layers of tissue that surround the kidney is the | Renal fascia
🗑
|
||||
| In renal interstitial fluid | Sodium chloride concentration increases from cortex to medulla
🗑
|
||||
| Filtration of blood | Occurs in glomerulus
🗑
|
||||
| The loop of Henle is associated with | Reabsorption
🗑
|
||||
| A function of the kidney is to | Regulate blood ionic composition
🗑
|
||||
| Which of the following molecules cannot pass the filtration membranes in the kidney? | Large proteins
🗑
|
||||
| The innermost layer of the three layers of tissue that protect the kidney is the | Renal capsule
🗑
|
||||
| The renal papillae contain papillary ducts which empty into the | Minor calyces
🗑
|
||||
| Reabsorption is the movement of molecules from the_________into the________. | renal tubules, peritubular capillaries
🗑
|
||||
| Very little water reabsorption occurs in the | thick ascending loop of Henle
🗑
|
||||
| Sodium ions move through the apical membranes of principal cells of the collecting duct by | Diffusion
🗑
|
||||
| Glomerular filtrate is produced as a result of | blood hydrostatic pressure
🗑
|
||||
| The external opening of the urinary system is the | external urethral orifice
🗑
|
||||
| The kidneys secrete the hormone erythropoietin, which functions to | control the rate of red blood cell production
🗑
|
||||
| The pathway of fluid through a juxtamedullary nephron | proximal convoluted tubule, descending loop of Henle, ascending loop of Henle, distal convoluted tubule
🗑
|
||||
| Urine reaches the urinary bladder through the | ureter
🗑
|
||||
| The nephron has two parts. What are they? | renal corpuscle and renal tubule
🗑
|
||||
| The visceral layer of Bowman's capsule is covered with specialized cells called | podocytes
🗑
|
||||
| Increased sodium and chloride ion concentrations in the interstitial fluid of the renal medulla is the result of | countercurrent mechanism
🗑
|
||||
| Externally, the kidney is protected and supported by connective tissue and | adipose tissue
🗑
|
||||
| Renal blood pressure remains fairly constant due to the function of the | juxtaglomerular apparatus
🗑
|
||||
| Chloride ions are actively reabsorbed from the | thick ascending limb of the loop of Henle
🗑
|
||||
| Potassium ions are actively secreted in the tubular fluid of the | distal convoluted tubule
🗑
|
||||
| Most reabsorption occures in the | proximal convoluted tubule
🗑
|
||||
| The proximal convoluted tubule is made up of | cuboidal cells with many microvilli
🗑
|
||||
| Net filtration pressure in the kidney | 10 mm Hg
🗑
|
||||
| Enzyme secreted by the juxtaglomerular apparatus | Renin
🗑
|
||||
| The main region of the kidney tubule that is impermeable to water is the | thick ascending limb of the loop of Henle
🗑
|
||||
| During the micturition reflex_________. | parasympathetic fibers conduct impulses from the spinal cord that cause contraction of the detrusor muscle
🗑
|
||||
| The only place in the kidney where filtration occurs is the | renal corpuscle
🗑
|
||||
| The urinary bladder in the female lies inferior to the | uterus
🗑
|
||||
| Bone, DNA, RNA, ATP, and cell membranes all have one thing in common. They all contain_________. | Phosphate
🗑
|
||||
| Intracellular fluid has | A higher concentration of potassium than interstitial fluid
🗑
|
||||
| Parathyroid hormone | Causes renal tubule cells to reabsorb calcium
🗑
|
||||
| Lower than normal blood concentration of sodium | Characterized by muscular weakness, tachycardia, and dizziness
🗑
|
||||
| Regulated by aldosterone | Sodium
🗑
|
||||
| Electrolytes | Dissociate into anions and cations
🗑
|
||||
| Sodium Ions | Necessary for generation of action potentials
🗑
|
||||
| Reabsorption of sodium from the tubules of the nephron establishes an osmotic gradient that causes______to move back into the blood. | Water
🗑
|
||||
| Hyperventilation during a panic attack causes an increase in blood_______. | pH
🗑
|
||||
| The only way the body can get rid of the huge acid load produced by metabolic reactions is to | excrete hydrogen ions in the urine
🗑
|
||||
| The urinary bladder in the male lies anterior to the | Rectum
🗑
|
Review the information in the table. When you are ready to quiz yourself you can hide individual columns or the entire table. Then you can click on the empty cells to reveal the answer. Try to recall what will be displayed before clicking the empty cell.
To hide a column, click on the column name.
To hide the entire table, click on the "Hide All" button.
You may also shuffle the rows of the table by clicking on the "Shuffle" button.
Or sort by any of the columns using the down arrow next to any column heading.
If you know all the data on any row, you can temporarily remove it by tapping the trash can to the right of the row.
To hide a column, click on the column name.
To hide the entire table, click on the "Hide All" button.
You may also shuffle the rows of the table by clicking on the "Shuffle" button.
Or sort by any of the columns using the down arrow next to any column heading.
If you know all the data on any row, you can temporarily remove it by tapping the trash can to the right of the row.
Embed Code - If you would like this activity on your web page, copy the script below and paste it into your web page.
Normal Size Small Size show me how
Normal Size Small Size show me how
Created by:
jarushing
Popular Nursing sets