FINALS: URINARY SYSTEM Flashcards by Chin Lys

Blood pH must remain between _______ to maintain homeostasis

7.35 & 7.45

How well did you know this?

Not at all

Perfectly

pH above 7.45

ALKALOSIS

How well did you know this?

Not at all

Perfectly

pH below 7.35

ACIDOSIS

How well did you know this?

Not at all

Perfectly

arterial pH between 7.35 & 7.0

PHYSIOLOGICAL ACIDOSIS

How well did you know this?

Not at all

Perfectly

Most ions originate as byproducts of cellular metabolism

MAINTAINING ACID-BASE BALANCE IN BLOOD

How well did you know this?

Not at all

Perfectly

Most acid-base balance is maintained by the

kidneys

How well did you know this?

Not at all

Perfectly

Other acid-base controlling systems

 Blood buffers
 Respiration

How well did you know this?

Not at all

Perfectly

Systems of 1 or 2 molecules that act to prevent dramatic changes in H+ concentrations when acids/bases are added

BLOOD BUFFERS

How well did you know this?

Not at all

Perfectly

Bind to H+ when pH ____

drops

How well did you know this?

Not at all

Perfectly

Release H+ when pH _____

rises

How well did you know this?

Not at all

Perfectly

1st line of defense in resisting pH changes

BLOOD BUFFERS

How well did you know this?

Not at all

Perfectly

3 MAJOR CHEMICAL BUFFER SYSTEMS:

 Bicarbonate buffer system
 Phosphate buffer system
 Protein buffer system

How well did you know this?

Not at all

Perfectly

Mixture of carbonic acid (H2CO3) & sodium bicarbonate (NaHCO3)

BICARBONATE BUFFER SYSTEM

How well did you know this?

Not at all

Perfectly

______ react with strong acids to change them to weak acids

Bicarbonate ions (HCO3‾)

How well did you know this?

Not at all

Perfectly

______ dissociates in the presence of a strong base to form a weak base and water.

Carbonic acid

How well did you know this?

Not at all

Perfectly

prevents excessive water loss in urine

ADH

How well did you know this?

Not at all

Perfectly

regulates Na+ content of ECF

ALDOSTERONE

How well did you know this?

Not at all

Perfectly

Triggered by the renin-angiotensin mechanism

REGULATION OF WATER & ELECTROLYTE REABSORPTION

How well did you know this?

Not at all

Perfectly

This general role of the kidneys involves a complex combination of renal functions:

-Secretion of renin
-Secretion of erythropoietin
-Conversion of the steroid prohormone vitamin D
-Gluconeogenesis

How well did you know this?

Not at all

Perfectly

a protease important for the regulation of blood pressure by cleaving circulating angiotensinogen to angiotensin I;

renin

How well did you know this?

Not at all

Perfectly

a glycoprotein growth factor that stimulates erythrocyte production in red marrow when the blood O2 level is low;

erythropoietin

How well did you know this?

Not at all

Perfectly

to the active form (1,25-dihydroxyvitamin D3 or calcitriol);

Conversion of the steroid prohormone vitamin D, initially produced in the skin

How well did you know this?

Not at all

Perfectly

during starvation or periods of prolonged fasting, making glucose from amino acids to supplement this process in the liver.

Gluconeogenesis

How well did you know this?

Not at all

Perfectly

ORGANS & FUNCTION OF THE URINARY SYSTEM

KIDNEYS
URETERS
URINARY BLADDER
URETHRA

How well did you know this?

Not at all

Perfectly

 Regulate aspects of homeostasis: water balance, electrolytes, acid-base balance in blood, BP (renin) , RBC production (EPO), activation of vitamin D  Excretes wastes in urine

KIDNEYS

Transport urine from kidneys to urinary bladder

URETERS

Stores urine & expels it into urethra

URINARY BLADDER

Discharges urine from body

URETHRA

Lie against the dorsal body wall in a retroperitoneal position in the superior lumbar region

KIDNEYS

At the level of T12 to L3

KIDNEYS

_____ is slightly lower than the left

Right kidney

Attached to ureters, renal blood vessels, & nerves at renal hilum

KIDNEYS

Atop each is an adrenal gland

KIDNEYS

Adult: 12 cm (5in) long, 6 cm (2.5in) wide, & 3 cm (1in) thick

KIDNEYS

COVERINGS OF KIDNEY

FIBROUS CAPSULE PERIRENAL FAT CAPSULE RENAL FASCIA

Smooth, transparent sheet of dense irregular connective tissue that is continuous with the outer coat of the ureter

FIBROUS CAPSULE

Barrier against trauma & helps maintain the shape of kidney

FIBROUS CAPSULE

Mass of fatty tissue surrounding the fibrous capsule

PERIRENAL FAT CAPSULE

Protects the kidney from trauma & holds it firmly in place within the abdominal cavity

PERIRENAL FAT CAPSULE

Thin layer of dense irregular connective tissue

RENAL FASCIA

Anchors the kidney to the surrounding structures & to the abdominal wall

RENAL FASCIA

outer region

RENAL CORTEX

inside the cortex

RENAL MEDULLA

Triangular regions with a striped appearance

Renal/medullary pyramids

portions of the renal cortex that extend between renal pyramids

Renal columns

inner collecting tube

RENAL PELVIS

cup-shaped structures that funnel urine towards the renal pelvis

Calyces

 The structural and functional units of the kidneys  Responsible for forming urine

NEPHRONS

MAIN STRUCTURES OF NEPHRON

RENAL CORPUSCLE RENAL TUBULE

blood plasma is filtered

RENAL CORPUSCLE

capillary network

Glomerulus

surrounds the glomerulus & its inner layer is made up of podocytes

Glomerular capsule (Bowman’s capsule)

(filtered fluid (glomerular filtrate) passes before entering a collecting ducts): 3 cm long

RENAL TUBULE

3 TYPES OF RENAL TUBULE

 Proximal convoluted tubule (PCT)  Nephron loop (loop of Henle)  Distal convoluted tubule (DCT)

2 TYPES OF NEPHRONS

CORTICAL NEPHRONS JUXTAMEDULLARY NEPHRONS

CORTICAL NEPHRONS

 Located entirely in the cortex  Includes most nephrons

Found at the boundary of the cortex & medulla

JUXTAMEDULLARY NEPHRONS

CAPILLARY BEDS ASSOCIATED WITH NEPHRONS

GLOMERULUS PERITUBULAR CAPILLARIES

 Feeder vessel: afferent arteriole  Receives blood that has passed through glomerulus: efferent arteriole

GLOMERULUS

 Arise from efferent arteriole of the glomerulus  Normal, low-pressure capillaries  Attached to a venule  Cling close to the renal tubule  Reabsorb (reclaim) some substances from collecting tubes

PERITUBULAR CAPILLARIES

 H2O & most solutes in blood plasma move across the wall of the glomerulus, where they are filtered & move into thee glomerular capsule & then into the renal tubule  Nonselective passive process  Water and solutes smaller than proteins are forced through capillary walls  Blood cells cannot pass out to the capillaries

GLOMERULAR FILTRATION

is collected in the glomerular capsule and leaves via the renal tube.

Filtrate

Glomerular Filtration Rate (GFR):

125 mL/min

Filtration occurs through a structure of three parts:

- The fenestrations of the capillary endothelium, which blocks blood cells and platelets - The thick, combined basal laminae, or GBM, which restricts large proteins and some organic anions - The filtration slit diaphragms between pedicels, which restrict some small proteins and organic anions.

 1st function to be affected in renal disease  Begins as soon as the filtrate enters PCT  The peritubular capillaries reabsorb several materials: some water, glucose, amino acids, ions  Some reabsorption is passive, most is active

TUBULAR REABSORPTION

MATERIALS NOT REABSORBED:

- Nitrogenous waste products - Urea - Uric acid - Creatinine - Excess water

 Tubular reabsorption in reverse  Some materials (H+, K+, creatinine, drugs) move from the peritubular capillaries into the renal tubules  Materials left in the renal tubule move toward the ureter & make their way into the urine.

TUBULAR SECRETION

2 MAJOR FUNCTIONS OF TUBULAR SECRETION

1. Regulation of the acid-base balance in the body through the secretion of hydrogen ions. 2. Elimination of waste products not filtered by the glomerulus.

major site for removal of nonfiltered substances

Proximal Convoluted Tubule

Kidneys filters____

150-180 L of blood plasma

Only about ____ of urine are produced

1-18 L

components same as blood plasma (except proteins)

Filtrate

nitrogenous wastes & unneeded substances

Urine

Substance: Glucose Name of condition: ___ Nonpathological: × Pathological: ×

Glycosuria

Substance: Glucose Name of condition: Glycosuria Nonpathological: _____ Pathological: ×

Excessive intake of sugary foods

Substance: Glucose Name of condition: Glycosuria Nonpathological: Excessive intake of sugary foods Pathological: _____

Diabetes mellitus

Substance: Proteins Name of condition: ___ Nonpathological: × Pathological: ×

Proteinuria

Substance: Proteins Name of condition: Proteinuria Nonpathological: _____ Pathological: ×

Physical exertion, pregnancy

Substance: Proteins Name of condition: Proteinuria Nonpathological: Physical exertion, pregnancy Pathological: ____

Glomerulonephritis, hypertension

Substance: Pus (WBCs and bacteria) Name of condition: _____ Possible causes: ×

Pyuria

Substance: Pus (WBCs and bacteria) Name of condition: Pyuria Possible causes: ___

Urinary tract infection

Substance: RBCs Name of condition: _____ Possible causes: ×

Hematuria

Substance: RBCs Name of condition: Hematuria Possible causes: ____

Bleeding in the urinary tract (due to trauma, kidney stones, infection)

Substance: Hemoglobin Name of condition: _____ Possible causes: ×

Hemoglobinuria

Substance: Hemoglobin Name of condition: Hemoglobinuria Possible causes: ____

Various: Transfusion reaction, hemolytic anemia

Substance: Bile pigment Name of condition: _____ Possible causes: ×

Bilirubinuria

Substance: Bile pigment Name of condition: Bilirubinuria Possible causes: _____

Liver (hepatitis) disease

 2 slender attaching the kidney to the bladder  25-30 cm (10-12 in) long & 6 mm (1/4 in) in diameter  Peristalsis (contraction of smooth muscle layers in their walls) aids gravity in urine transport  Small valvelike folds of bladder mucosa: prevents urine from flowing back into the ureters

URETERS

_____contraction of smooth muscle layers in their walls

Peristalsis

 Smooth, collapsible, muscular sac  Temporarily stores urine  Trigone (3 openings)

URINARY BLADDER

Trigone (3 openings)

- 2 ureter openings (ureteral orifices) - Single opening of urethra (internal urethral orifice: drains the bladder

prostate gland surrounds the neck of the bladder

Males

 3 layers of smooth muscle (detrusor muscle)  Mucosa made of transitional epithelium  Walls are thick & folded in an empty bladder  Bladder can expand significantly without increasing internal pressure

URINARY BLADDER

Thin-walled tube that carries urine by peristalsis from the bladder to the outside of the body

URETHRA

Release of urine is controlled by 2 sphincters:

INTERNAL URETHRAL SPHINCTER EXTERNAL URETHRAL SPHINCTER

(involuntary): smooth muscle

INTERNAL URETHRAL SPHINCTER

(voluntary): skeletal muscle

EXTERNAL URETHRAL SPHINCTER

The male urethra is longer and consists of three segments:

PROSTATIC URETHRA MEMBRANOUS URETHRA SPONGY URETHRA

3-4 cm long, extends through the prostate gland and is lined by urothelium

PROSTATIC URETHRA

short segment, passes through an external sphincter of striated muscle and is lined by stratified columnar and pseudostratified columnar epithelium

MEMBRANOUS URETHRA

15 cm in length, is enclosed within erectile tissue of the penis and is lined by stratified columnar and pseudostratified columnar epithelium with stratified squamous epithelium distally

SPONGY URETHRA

2 sphincters control the flow of urine from the bladder, both must open to allow voiding:

INTERNAL URETHRAL SPHINCTER EXTERNAL URETHRAL SPHINCTER

relaxed after stretching of the bladder - Activation is from an impulse sent to the spinal cord & then back via the pelvic splanchnic nerves

INTERNAL URETHRAL SPHINCTER

must be voluntarily relaxed

EXTERNAL URETHRAL SPHINCTER

 Falling/floating kidney, is an inferior displacement/dropping of the kidney  Cause: Kidney is not securely held in place by adjacent organs/its covering of fat  Dangerous because the ureter may kink & block urine flow---exerts pressure on kidney tissue (hydronephrosis)

NEPHROPTOSIS

 Abnormally low urinary output (100-400 mL/day)  Indicates that glomerular BP is too low to cause filtration  Other causes: transfusion reactions & acute inflammation/from crush injuries of the kidneys

OLIGURIA

<100 mL/day urine

ANURIA

 Formed by the occasional precipitation & solidification of the crystals of salts present in urine  Commonly contain crystals of calcium oxalate, uric acid or calcium phosphate

RENAL CALCULI (KIDNEY STONES)

 Decrease/cessation of glomerular filtration  Kidneys abruptly stop working entirely  Main feature: suppression of urine flow (oliguria/anuria)

ACUTE RENAL FAILURE

Infection of a part of the urinary system/presence of large numbers of microbes in urine

URINARY TRACT INFECTION (UTI)

inflammation of urethra

URETHRITIS

inflammation of urinary bladder

CYSTITIS

kidney inflammation

PYELONEPHRITIS/PYELITIS

Symptoms: DYSURIA (painful urination), urinary urgency & frequency, fever

URINARY TRACT INFECTION (UTI)

 Unable to voluntarily control the external sphincter  Normal in infants & children 2-3 years old

INCONTINENCE

TYPES OF INCONTINENCE

- Stress incontinence - Urge incontinence - Overflow incontinence - Functional incontinence

 Bladder is unable to expel its contained urine  Causes: - After surgery in which anesthesia has been given - Hyperplasia (enlargement) of prostate gland

URINARY RETENTION

 ADH is not released, huge amounts of very dilute urine (25 L/day) flush from the body day after day  Can lead to severe dehydration & electrolyte imbalances  Always thirsty & have to drink fluids almost continuously to maintain normal fluid balance

DIABETES INSIPIDUS

 Hypoaldosteronism  Have polyuria (excrete large volumes of urine) & lose tremendous amounts of salt & water to urine

ADDISON’S DISEASE

Degenerative condition, 1 or both kidneys enlarge & have many blisterlike sacs (cysts) containing urine

ACUTE POLYCYSTIC KIDNEY DISEASE

 Condition found in male babies only  Urethral orifice is located on the ventral surface of the penis

HYPOSPADIAS

 Inflammation of the kidney that involves the glomeruli  Common cause: allergic reaction to the toxins produced by streptococcal bacteria that have recently infected another part of the body (the throat)

GLOMERULONEPHRITIS

 The thickening and loss of function in the GBM produced as part of the systemic microvascular sclerosis in diabetes mellitus  Is the leading cause of (irreversible) endstage kidney disease in the United States, treatment requires either a kidney transplant or regular artificial hemodialysis

DIABETIC GLOMERULOSCLEROSIS

 One of the most common problems caused by sickle cell disease  Occurs when the affected erythrocytes sickle in the vasa recta, because of the low oxygen tension there.  The nephropathy results from renal infarcts, usually within the renal papillae or pyramids

SICKLE CELL NEPHROPATHY

Bacterial infections of the urinary tract can lead to inflammation of the ____

RENAL PELVIS and CALYCES, or PYELONEPHRITIS

bacteria often move from one or more minor calyx into the associated renal papilla, causing accumulation of neutrophils in the collecting ducts.

ACUTE PYELONEPHRITIS

 Or the inflammation of the bladder mucosa  Is the most frequent problem involving this organ  Such inflammation is common during urinary tract infections

CYSTITIS

 It can also be caused by immunodeficiency, urinary catheterization, radiation, or chemotherapy.  Chronic cystitis can cause an unstable urothelium, with benign urothelial changes involving hyperplasia or metaplasia  Bladder cancer is usually some form of transitional cell carcinoma arising from unstable urothelium.

CYSTITIS