Practicum 2 Urinary Flashcards
How many liters of blood do the kidneys filter daily?
200 L
Blood filtration allows what to leave the body in urine?
Toxins, metabolic wastes, and excess ions
The urinary system regulates:
volume and chemical makeup of blood
The urinary system maintains:
The proper balance between water and salts and acids and bases
The urinary system promotes what during prolonged fasting
Gluconeogenesis
Production of ____ helps regulate blood pressure and ____ to stimulate RBC production
Renin, Erythropoietin
Activation of ____ metabolizes its active form _____
Vitamin D, Vitamin D3–Calcitriol
Organs of the Urinary System:
2 kidneys, 2 ureters, 1 urinary bladder, urethra
The ___ is the large fat pad that surrounds the ____ in the posterior region of the ____ cavity
Perirenal fat capsule, kidney, abdominal
Approximately ____ of systemic cardiac output flows through the kidneys each minute
1/4 (1200 ml)
____ into and ____ out of the kidneys follow similar paths
Arterial flow, venous flow
What is the structural and functional unit of the kidney and how many per kidney?
The nephron, >1.500,000
The nephron consists of:
- Renal (Bowmans) Corpuscle
- Proximal convoluted tubule
- Descending and ascending limbs of the loop of Henle
- Distal convoluted tubule
- Collecting tubule
The nephron produced what:
Urine
Filters plasma to form filtrate
Renal Corpuscle
Converts filtrate into urine
Renal Tubule
The renal corpuscle is made up of what?
Glomerulus and Glomerular Capsule
A tuft of capillaries associated with a renal tubule
Glomerulus
Blind, cup-shaped end of a renal tubule that completely surrounds the glomerulus
Glomerular Capsule
Blood enters through the:
Afferent arteriole
Blood leaves through the:
Efferent arteriole
2 Types of Nephrons:
Cortical and Juxtamedullary
Cortical Nephrons have:
- Short nephron loops
- Glomerulus is further away from cortex-medulla junction
- Efferent arteriole supplies peritubular capillaries
Juxtamedullary Nephrons have:
- Long nephron loops
- Glomerulus closer to cortex medulla junction
- Efferent arterioles supply vasa recta
Glomerular Filtration (1)
Afferent arterioles feed the first capillary bed (i.e., glomerulus).
Has high pressure due to
High resistant arteriole vessels
Afferent feeder is larger in diameter than efferent (drainer)
Efferent arterioles drain glomerulus.
High pressure forces filtrate out of capillary bed into the capsule.
Juxtaglomerular cells (part of JGA) - Function as blood pressure sensors in the walls of the afferent arterioles.
Tubular Reabsorption (2)
75-80% of reabsorption occurs from the proximal convoluted tubule.
Reabsorbs into the 2nd capillary bed, peritubular capillary bed.
Reabsorption depends on selective needs of the body.
Almost all water (osmosis), glucose and amino acids.
Some ions for blood pH and electrolytes.
Waste products (urea, creatinine, uric acid, drug metabolites) are hardly reabsorbed.
What is the reverse process of tubular reabsorption called? What is secreted and where?
Tubular Secretion (3)
Extra ions, creatinine, and drug metabolites secreted from the peritubular capillaries to the tubular cells
Term for voiding urine:
Micturition
Filling of bladder activates
Stretch receptors which
trigger a parasympathetic
response:
-Causes relaxation of the
Internal urethral
sphincter
(smooth muscle;
Involuntary reflex)
-The Pons is also activated
and it triggers relaxation
of the external
urethral sphincter
(skeletal muscle
which is under
voluntary control)
Bladder capacity is _____, but _____
triggers the ______
600-800 ml, ~200 - 300 ml, Micturition Reflex
Every 24 hrs: ~150-180 liters of blood is filtered through kidneys
Creating 1.0-1.8 liters of urine
Constituents of urine: water, urea, sodium, potassium, phosphate, sulfate ions, creatinine, uric acid.
General Characteristics of urine
Color- straw to yellow from
urochrome (product of
Hemoglobin metabolism).
Odor- Ammonia
pH- slightly acidic (~pH = 6; range pH 4.5-8)
Specific gravity (1.001-1.030), i.e., weight compared to water (1.000)
pyuria: WBC pus in urine
hematuria: RBC in urine
The results of a urine dipstick test, known as _____ may point to a diagnosis of ____, _____, ____, or a ______.
Urinalysis, urinary tract infection (UTI), kidney disease, diabetes, urinary tract injury
If urinalysis test results are ___, other tests will be needed before a definite diagnosis can be made.
Abnormal
Abnormal Urinary Constituents
Glucose → Glycosuria/Glucosuria
Uncontrolled diabetes mellitus; Excessive carbohydrate intake
Protein → Proteinuria/Albuminuria
Severe hypertension; glomerulonephritis; bacterial toxins; excessive physical exertion; pregnancy
Ketone Bodies → Ketonuria
Diabetes; starvation; low carbohydrates diets
Erythrocytes/RBCs → Hematuria
Bleeding in the tract due to kidney stones, urinary tract tumors, trauma to urinary tract organs; Glomerulonephritis
Hemoglobin → Hemoglobinuria
Renal disease; hemolytic anemia; transfusion reactions
Nitrites → Nitrituria
Urinary tract infections (UTIs)
Bile pigments → Bilirubinuria
Liver disease; gallstones
Leukocytes/WBCs → Pyuria
Urinary tract infections (UTIs); gonorrhea
Urine Sediments are composed of two parts, what are they and what do they entail?
Unorganized sediments: chemical substances that form crystal/precipitate
Organized sediments: come form red blood cells and white blood cells and include casts
Medical term for kidney stone disease
Urolithiasis
Medical term for kidney stones
Renal Calculi
Cylindrical structures produced by the kidney and present in the urine in certain disease states
Urinary casts
Urinary casts form in the _____ and _____, then dislodge and pass into the _____ where they can be detected by microscopy
Distal convoluted tubule, collecting ducts of nephrons, urine
Abnormal Urinary Constituents:
Urinary Casts and Urine sediments
