Chapter 26: The Urinary System Part 1 Flashcards
What are the 3 general functions of the Urinary System?
- Excretion: removal of organic wastes from body fluids
- Elimination: discharge of waste products
- Homeostatic regulation: of blood plasma volume and solute concentration
What are the 8 functions of the kidney?
- regulation of blood ionic concentrations
- regulation of blood pH
- regulation of blood volume
- regulation of blood pressure
- maintenance of blood osmolarity
- production of hormones
- regulation of blood glucose level
- excretion of wastes and foreign substances
Kidney Function: regulation of blood ionic concentrations
help regulate blood concentrations of several ions: sodium, potassium, calcium, chloride and phosphate
Kidney Function: regulation of blood pH
controlling amounts of hydrogen ion excretion and bicarbonate ion reabsorption
Kidney Function: regulation of blood volume
controlling amounts of water excreted or reabsorbed
Kidney Function: regulation of blood pressure
secretion of renin (enzyme) which is part of the RAAS pathway
Kidney Function: maintenance of blood osmolarity
(number of particles/L solution) iso-osmotic concentration: 300 mOsm/L
regulates excretion of water and solutes
Kidney Function: production of hormones
erythropoieten (EPO)
converts vitamin D to active form: Calcitriol
Kidney Function: regulation of blood glucose level
if necessary, gluconeogenesis from glutamine (an amino acid)
Kidney Function: excretion of wastes and foreign substances
urine: excretion of waste
- ammonia and urea (deamination of amino acids)
- catabolism of bilirubin (urobilin), creatine phosphate (creatine), and uric acid (nucleic acid)
- by products of drug and toxin degradation from the liver
location and external anatomy of the kidney
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3 Layers of Supportive Tissue Surrounding Kidney
- Renal Fascia
- Perirenal Fat Capsule (Adipose Capsule)
- Fibrous Capsule (Renal Capsule)
Renal Fascia
anchoring outer layer of dense fibrous irregular connective tissue
Perirenal Fat Capsule (Adipose Capsule)
mass of fatty cushion (protects and holds kidneys in place)
Fibrous Capsule (Renal Capsule)
- transparent, fibrous (dense irregular CT), smooth capsule that prevents spread of infection to kidney
- continuous with outer coat of ureter
renal ptosis or nephroptosis
condition in which one or both kidneys drop to a lower position
renal ptosis is caused by
• Can be caused by loss of surrounding fatty tissue capsule that holds kidneys in normal position or renal fascia is deficient
– Seen with emaciation or rapid weight loss
– Renal ptosis may cause a ureter to become kinked, causing urine to back up and exert pressure on kidney tissue
– Common (1 in 4) affect with some degree of weakening of fibrous bands (10X more common in females)
Hydronephrosis
-backup of urine from ureteral obstruction or other causes
–Can severely damage kidney, leading to tissue death and renal failure
Internal gross anatomy of the kidney
- Renal Cortex
- Renal Medulla
- Renal Pelvis
Renal Cortex
granular-appearing superficial region
Renal Medulla
deep to cortex, composed of cone-shaped Renal (Medullary) Pyramids
• Broad base of pyramid faces cortex
• Renal Papilla, tip of pyramid, points internally
• Renal pyramids are separated by renal columns, inward extensions of cortical tissue
• Lobe: medullary pyramid and its surrounding cortical tissue
Renal Pelvis
Funnel-shaped chamber continuous with ureter
• Minor calyces
• Major calyces
Minor calyces
– Cup-shaped areas that collect urine draining from
pyramidal papillae
Major calyces
– Areas that collect urine from minor calyces – Empty urine into renal pelvis