A&P chapter 18 urinary system
Female urethra
1.2 inches long
Composition of urine
95% water and 5% dissolved substances, dissolve substances include nitrogenious wastes such as uric acid, creatinine, as well as other solids such as sodium, potassium, and sulfates. Glucose should not be in urine
Urinary bladder
A collapsible muscular sac that stores urine. sits behind the symphysis pubis and below the peroneal membrane. In women it resides in front of the vagina and uterus and men it rests on top of the prostate gland
Calyx
A cup like structure that collects year and leaving the papilla of the kidney
Angiotensin
A plasma protein produced when renin is released from the kidney, angiotensin II stimulates the adrenal gland to secrete aldosterone
Urethra
A small tube that conveys urine away from the bladder and out of the body
Urination
Also called micturition, or voiding, requiring input from the central nervous system
Renal insufficiency
Also called renal failure, nephrons have been destroyed through disease or injury, impairing the ability of the kidneys to function
Kidney stones
Also known as renal calculi, minerals crystallize in the renal pelvis, many times these calculi are small enough to pass unnoticed, may be large enough to block the renal pelvis or ureter. Excruciating pain results as the ureter contracts.
Afferent Arterioles
Arise from the smaller arteries,supplies blood to one nephron, located in the cortex, our region
Note
Because the ureter is so narrow, kidney stones can easily become lodged in obstruct the flow of urine
Hemodialysis
Blood is pumped from the patients radial artery to a dialysis machine, which is sometimes called an artificial kidney, blood flows through a series of semi permeable tubes immersed in dialysis fluid
Efferent arteriole
Blood leaves the glomerulus through an ___________
Hilum
Blood vessels, the ureters, and nerves, enter and leave the kidney through a slit called _________. Located in a concave notch on the medial side.
Renal artery
Branches off of the abdominal aorta, brings blood to the kidney
Glomerulus
Cluster of capillaries that are part of the renal corpuscle's in the nephrons.
Urine formation
Creation of urine by the nephrons involves three processes, glomerular filtration, tubular reabsorption, and tubular secretion
Glomerular filtration
First step in the creation of urine from blood plasma, water and small solutes filter out of the blood and into the surrounding space of Bowmans capsule
Types of dialysis
Hemodialysis and peritoneal dialysis
Aldosterone
Hormone that causes the distal convoluted tubule to retain sodium, which leads to the retention of water, resulting in increased blood pressure
Antidiuretic hormone/ADH
Hormone that inhibits diuresis by stimulating the kidneys to conserve water
Chronic renal insufficiency
Loss of function developed over years, such as from diabetes, hypertension, destroys the nephrons, damage so extensive that the kidneys can no longer effectively clear blood plasma of waste damage your reversible, transplant or dialysis necessary
Specific gravity
Measurement that indicates the amount of solid matter in a liquid
Peritubular capillaries
Network of capillaries surrounding the renal tubule's Note, blood flows from the _________ into larger and larger veins that eventually feed into the renal vein
Characteristics of urine
Normal color, trans parent pale yellow to Amber, odor, mild, specific gravity, indicates the amount of solid matter in a liquid, concentration of urine, higher the concentration dehydration, pH,average of 6.0, acidic
Renal corpuscle
One of the main components of nephrons, consisting of a glomerulus and the Bowmans capsule that filters blood plasma
Tubular secretion
Process whereby chemicals are added to the filtrate in the renal tubule's
Storage and elimination of urine
Remaining structures of the urinary system are the ureter's, urinary bladder, and urethra
Renal tubule
Series of tubelike structures within the nephron, where urine is formed
Hydronephrosis
Urine backup to the kidney
Internal urethral sphincter
Where the urethra leaves the bladder, contracts in voluntary to retain urine in the bladder
Nephrons
Functional unit of the kidney, the filtration units of the kidney. Contains two main components, renal corpuscle and renal tubule. Note: outer regions of the kidney are packed with over 1 million
Glucose
Glucose is reabsorbed and should never be in the urine
Urinary system
Include, kidneys, ureter's, urinary bladder, and urethra. Filters blood through kidneys, remove potential poisons, I just the water content of blood, tweak the levels of sodium and potassium, just a pH levels, regulation of blood pressure in the production of red blood cells
Collecting duct
Last section of renal tubule,Receives drainage from the distal convoluted tubule's of several different nephrons, passes into a renal pier mid, where it merges with other collecting ducts to form one tube
Renal vein
Leaves the kidney through the ________ which empties into the inferior vena cava
Kidneys
Lie against the posterior -behind, abdominal wall and underneath the 12th rib. Note, the ________ on the right sits lower than the left because of the space occupied by the liver about it
Acute renal failure
Loss of function may occur suddenly, result of an infection, drugs or injury, when cause of renal failure is treated, kidney function may return to normal
Note
Most adults produce 1 to 2 L of urine a day.
Male urethra
Much longer, 7.9 inches, passes through the center of the prostate gland, curves around to enter the penis, and then exits the body at the tip of the penis, conveying urine, it also conveys semen
Rugae
Mucus transitional epithelium lines the bladder, when the bladder is relaxed, this layer of tissue forms folds, Note: the bladder has a maximum capacity of 800 ML
Ureters
Muscular tube connecting the renal pelvis of the kidney with the bladder. Note, peristaltic waves help propel urine from the renal pelvis toward the bladder. Passageway from kidney to bladder
Renal innervation
Nerves also enter the kidney at the Hilum, controlling the diameter of the vessels, blood pressure drops, the nerves stimulate the release of renin, an enzyme that triggers process for restoring blood pressure.
Tubular reabsorption
Process whereby chemicals are removed from filtrate in the renal tubule's and return to the blood.
Loop of Henley/nephron loop
Second section of renal tubule, U shaped portion of the renal tubule consisting of the descending limb and the ascending limb
Parathyroid hormone/PTH
Secreted by the parathyroid glands in response to low blood calcium levels, increases calcium levels when low, reabsorbs calcium, excretes phosphate
Process of tubular reabsorption and secretion
Sodium, water, glucose, amino acids, potassium, reabsorbed into the blood ,Tubular secretion of hydrogen ions occurs helping regulate the body's pH. Water diffuses out of the descending limb of a loop of Henle, further concentrating the filtrate. The distal convoluted tubule and collecting ducks reabsorb variable amounts of water and salts
Glomerular filtration rate/ GFR
The amount of fluid filtered by both kidneys, equals about 180 L each day. The body reabsorbs about 99% of this, leaving 1 to 2 L to be excreted as urine
Bowmans capsule
Two layers of epithelial cells that envelop the glomerulus in an open ended covering, also called a glomerular capsule
Oliguria
urine output less than 400 ml per day
External urinary meatus
The opening of the urethra leading to the outside of the body
Diuresis
The passage of large amounts of urine
Peritoneal dialysis
The peritoneum serves as a semi permeable membrane, dialysis fluid is introduced into the peritoneal cavity through a catheter. Fluid is left in the body cavity for a specific time during which time waste products diffuse out of the blood and into the dialysate. At the end of specified time, fluid is drained and discarded
Detrusor muscle
The wall of the bladder, consists of three layers
Distal convoluted tubule
Third section of renal tubule, After returning to the cortex, the ascending limb coils again forming the _________
Lithotripsy
Doctors often treat renal calculi with this technique, uses ultrasound to disintegrate the stone into particles small enough to pass through the urinary tract
Excretion
Eliminating waste from the body
Renin
Enzyme released by the kidneys in response to a drop in blood pressure that causes the conversion of angiotensinogen into angiotensin 1
Respiratory system
Excrete carbon dioxide and water
Urinary system
Excretes Metabolic wastes, drugs, hormones, salt and water
Digestive system
Excretes water, carbon dioxide, lipids, bile pigments and other metabolic wastes
Integumentary system
Excretes water, electrolytes, lactic acid and urea through sweat
Proximal convoluted tube
First section of renal tubule, Arising directly from Bowmans capsule, is a winding, convoluted portion of the renal tube, thousands of micro Villi that allow absorption to occur line the inside
Renal Medulla
Forms the inner region of the kidney, the site of urine collection
Renal cortex
Forms the outer region of the kidney, the site of urine production