Urinary System

Question 1

Kidney terms: see lab objectives plus: retroperitoneal, adipose capsule, renal fascia

Answer 1

• retroperitoneal-the space between the peritoneum and the posterior abdominal wall that contains especially the kidneys and associated structures, the pancreas, and part of the aorta and inferior vena cava, SAD PUCKER, suprarenal gland, aorta, duodenum, pancreas, ureters, colon, kidneys, esophagus, rectum
• adipose capsule- a layer of adipose tissue surrounding the renal capsule that protects and supports the kidney.
• renal fascia- a dense outer layer of connective tissue that anchors the kidney to surrounding structures.

Question 2

Nephron terms: see lab objectives plus: filtrate, fenestrated capillaries, podocytes, pedicels, filtration slits, tubular reabsorption, tubular secretion, tall microvilli, “thick” and “thin” descending loop, “thick” and “thin” ascending loop, counter current multiplier, cortical nephron, juxtamedullary nephrons, secretion, aldosterone, ADH, hilum, kidney stones, detrusor muscle, rugae, stretch receptors, micturition reflex, internal sphincter, external sphincter(urethral), Meiosis

Answer 2

• filtrate- the water/dissolved filtrates in the blood plasma that is passively moved out of the glomerulus into the capsular space of the renal corpuscle due to pressure differences across the filtration membrane.
• fenestrated capillaries-are pores that will allow larger molecules though
• podocytes- special cells in the glomerular capsule of the visceral layer, help form filtration barrier in glomerulus as well as support structure/function.
• pedicels- long processes of podocytes, wrap around the glomerular capillaries to support the capillary wall but not completely ensheath it.
• filtration slits- thin spaces that separate pedicels, which allow materials from the blood plasma to pass into the capsular space.
• tubular reabsorption- occurs when substances in the filtrate move by diffusion or active transport across the wall of the renal tubules to return to the blood.
• tubular secretion- is the active transport of solutes out of the blood into the tubular fluid.
• tall microvilli- in proximal convoluted tubule, in the distal convoluted tubule there are short microvilli.
• “thick and thin” descending loop- thick then thin, thick=simple cuboidal, thin=simple scams
• “thick and thin” ascending loop- thin then thick, thin= simple scams, thick= simple cuboidal
• counter current multiplier- mechanism system is a mechanism that expends energy to create a concentration gradient. It is found widely in nature and especially in mammalian organs.
• cortical nephron- 85% of nephrons, because the bulk of the nephron resides solely in the cortex, and their relatively short nephron loops just barely penetrate the medulla.
• juxtamedullary nephrons- 15% of nephrons, called because their renal corpuscles lie close to the corticomedullary junction, and their long nephron loops extend deep into the medulla.
• secretion-
• aldosterone(adrenal cortex)/ADH(antidiuretic hormone, posterior pituitary)-, secreted in response to low blood volume or low solute concentration in the tubular fluid within the kidney. These hormones cause the distal convoluted tubule cells to increase water and sodium reabsorption from tubular fluid.
• ADH-(posterior pituitary)
• hilum- the entrance to the renal sinus. Structures such as the renal veins, artery, nerves and lymphatic vessels are located in the renal hilum.
• kidney stones-
• detrusor muscle-
• rugae-
• stretch receptors-
• microturition reflex-
• internal sphincter-
• external sphincter(urethral)-
• Meoisis-

Question 3

Nephron terms: see lab objectives plus: filtrate, fenestrated capillaries, podocytes, pedicels, filtration slits, tubular reabsorption, tubular secretion, tall microvilli, “thick” and “thin” descending loop, “thick” and “thin” ascending loop, counter current multiplier, cortical nephron, juxtamedullary nephrons, secretion, aldosterone, ADH, hilum, kidney stones, detrusor muscle, rugae, stretch receptors, micturition reflex, internal sphincter, external sphincter(urethral), Meiosis

Answer 3

• filtrate- the water/dissolved filtrates in the blood plasma that is passively moved out of the glomerulus into the capsular space of the renal corpuscle due to pressure differences across the filtration membrane.
• fenestrated capillaries-
• podocytes- special cells in the glomerular capsule of the visceral layer, help form filtration barrier in glomerulus as well as support structure/function.
• pedicels- long processes of podocytes, wrap around the glomerular capillaries to support the capillary wall but not completely ensheath it.
• filtration slits- thin spaces that separate pedicels, which allow materials from the blood plasma to pass into the capsular space.
• tubular reabsorption- occurs when substances in the filtrate move by diffusion or active transport across the wall of the renal tubules to return to the blood.
• tubular secretion- is the active transport of solutes out of the blood into the tubular fluid.
• tall microvilli- in proximal convoluted tubule, in the distal convoluted tubule there are short microvilli.
• “thick and thin” descending loop- thick then thin, thick=simple cuboidal, thin=simple scams
• “thick and thin” ascending loop- thin then thick, thin= simple scams, thick= simple cuboidal
• counter current multiplier-
• cortical nephron- 85% of nephrons, because the bulk of the nephron resides solely in the cortex, and their relatively short nephron loops just barely penetrate the medulla.
• juxtamedullary nephrons- 15% of nephrons, called because their renal corpuscles lie close to the corticomedullary junction, and their long nephron loops extend deep into the medulla.
• secretion-
• aldosterone(adrenal cortex)/ADH(antidiuretic hormone, posterior pituitary)-, secreted in response to low blood volume or low solute concentration in the tubular fluid within the kidney. These hormones cause the distal convoluted tubule cells to increase water and sodium reabsorption from tubular fluid.
• ADH-(posterior pituitary)
• hilum- the entrance to the renal sinus. Structures such as the renal veins, artery, nerves and lymphatic vessels are located in the renal hilum.
• kidney stones-small, hard mineral deposits that form inside your kidneys. The stones are made of mineral and acid salts. Stones crystallize when urine becomes concentrated.
• detrusor muscle- consists of 3 layers of smooth muscle that make up the muscularis, wall of urinary bladder that enlarges to contain urine and squeezes down to move urine out
• rugae- mucosal folds in bladder, allow for greater distension(enlargement)
• stretch receptors- activate and signal micturition reflex when bladder fills with urine and becomes distended
• micturition reflex- complex sequence of events that initiate expulsion of urine, 1. bladder fills activated stretch receptors that signal micturition reflex center, 2. impulses within parasympathetic of autonomic nervous system travel to the internal urethral sphincter + detrusor muscle, 3. smooth muscle in internal sphincter relaxes and the smooth muscle in the detrusor muscle contracts, 4. person’s conscious decision to urinate relaxes external urethral sphincter, 5. expulsion of urine facilitated by contraction of muscles in abdominal wall + expiratory muscles, 6. upon emptying of urinary bladder, the detrusor muscle relaxes + neurons of the micturition reflex are inactivated.
• internal sphincter- (involuntary, autonomous nervous system) surrounds neck of the bladder where urethra originates.
• external sphincter(urethral)- inferior to the internal sphincter + is formed by skeletal muscle fibers of the urogenital diaphragm.(voluntary controlled by somatic nervous system)
• Meoisis-is a type of cell division that reduces the number of chromosomes in the parent cell by half and produces four gamete cells. This process is required to produce egg and sperm cells for sexual reproduction.