THE URINARY SYSTEM Flashcards
name and locate the organs of the urinary system;
Kidneys- are large, bean-shaped organs towards the back of the abdomen (belly). They lie behind a protective sheet of tissue within the abdomen.
Ureters- are 25-30 cm long tubes lined with smooth muscle that exit the kidneys through the hilum and carry urine to the bladder.
Bladder- a pyramid-shaped organ which sits in the pelvis.
Urethra- the male urethra is 18-20 cm long, running from the bladder to the tip of the penis. The female urethra is 4-6 cm long and 6 mm wide. It is a tube running from the bladder neck and opening into an external hole located at the top of the vaginal opening.
list several functions of the kidneys in addition to urine formation;
- Filter blood and excrete toxic metabolic wastes
- Regulate blood volume, pressure, and osmolarity
- Regulate electrolytes and acid-base balance
- Secrete erythropoietin, which stimulates the production of red blood cells
- Help regulate calcium levels by participating in calcitriol synthesis
- Clear hormones from blood
- In starvation, they synthesize glucose from amino acids
name the major nitrogenous wastes and identify their sources
- Urea formation
- Proteins–> amino acids–> NH2 removed –> forms ammonia
- Liver converts ammonia to urea
- Uric acid
- Product of nucleic acid catabolism
- Creatinine
- Product of creatine phosphate catabolism
define excretion and identify the systems that excrete wastes.
Excretion—separating wastes from body fluids and eliminating them
Four body systems carry out excretion:
- Respiratory system
- CO2, small amounts of other gases, and water
- Integumentary system
- Water, inorganic salts, lactic acid, urea in sweat
- Digestive system
- Water, salts, CO2, lipids, bile pigments, cholesterol, and other metabolic waste
- Urinary system
- Many metabolic wastes, toxins, drugs, hormones, salts, H+, and water
describe the location and general appearance of the kidneys;
- Position, weight, and size
- Lie against posterior abdominal wall at level of T12 to L3
- Right kidney is slightly lower due to large right lobe of liver
- Rib 12 crosses the middle of the left kidney
- Retroperitoneal along with ureters, urinary bladder, renal artery and vein, and adrenal glands
identify the major external and internal features of the kidney;
- Shape and size
- About the size of a bar of bath soap
- Lateral surface is convex, and medial is concave with a slit, called the hilum
- Receives renal nerves, blood vessels, lymphatics, and ureter
- Three protective connective tissue coverings
- Renal fascia immediately deep to parietal peritoneum
- Binds it to abdominal wall
- Perirenal fat capsule: cushions kidney and holds it into place
- Fibrous capsule encloses kidney protecting it from trauma and infection
- Collagen fibers extend from fibrous capsule to renal fascia
- Still drop about 3 cm when going from lying down to standing up
- Renal parenchyma— glandular tissue that forms urine
- Appears C-shaped in frontal section
- Encircles renal sinus
- Renal sinus: cavity that contains blood and lymphatic vessels, nerves, and urine collecting structures
- Two zones of renal parenchyma
- Outer renal cortex
- Inner renal medulla
- Renal columns—extensions of the cortex that project inward toward sinus
- Renal pyramids—6 to 10 with broad base facing cortex and renal papilla facing sinus
- Lobe of kidney: one pyramid and its overlying cortex
- Minor calyx: cup that nestles the papilla of each pyramid; collects its urine
- Major calyces: formed by convergence of 2 or 3 minor calyces
- Renal pelvis: formed by convergence of 2 or 3 major calyces
- Ureter: a tubular continuation of the pelvis that drains urine down to the urinary bladder
briefly trace the flow of blood through the kidney;
trace the flow of fluid through the renal tubules;
explain how the nervous system and urethral sphincters control the voiding of urine.
Gluconeogenesis during prolonged fasting in kidneys form new glucose from
glycerol and amino acids
kidneys are protected by
11th and 12th ribs superiorly and inferior is exposed but protected overall by with its adrenal gland is surrounded by two layers of fat: the perirenal fat present between renal fascia and renal capsule and pararenal fat superior to the renal fascia.
How much cardiac output goes to the kidneys through the renal arteries?
25% (1200 ml)
kidneys are located
Kidneys are retroperitoneal in the body
anatomy of kidneys
Types of nephrons
Juxtamedullary nephrons:
Very long nephron loops, maintain salinity gradient in the medulla and help conserve water
Cortical nephrons:
Main type
Short nephron loops
