micturition, smooth muscle, transitional, rugae, trigone
Urinary bladder serves as the storage area until _____ occurs. Composed of _______and _____ tissues so that the bladder can stretch when full and then go back to its original shape when empty. Also possess___ and a ____.
Urethra, urethral sphincter
_____ drains urine from urinary bladder and transports the urine to the outside. In females, it only drains urine. In males, it drains urine and semen. Possess an internal and external _______.
The kidneys are located retroperitoneally on each side of the vertebral column between the ___ thoracic vertebrae and the ___ lumbar vertebra.
=outer most portion of the kidney which is light in color and has a granular appearance.
=a flat funnel shaped tube drains urine from the cortex and medulla toward the ureters.
= "middle" or rather the next deeper layer that possess many cone shaper masses called renal pyramids.
bring oxygenated unfiltered blood into the kidney
- The renal arteries branch into smaller and smaller vessels in the following order (S.L.I.A.I.A.G.E.P)
The ____ capillary beds transport blood to the veins in a processed deoxygenated form in the following sequence.
There are over 1million nephrons per kidney which do not ____. However, a person can survive as long as at least ___ of the nephrons are functional.
______=first capillary bed made of fenestrated capillaries which are exceptionally porous allowing large amounts of solutes to pass from blood and into the surrounding Bowman's capsule. This substance removed from blood is called ____.
Bowman's capsule, podocytes, simple squamous
_____=collection tubule that surrounds the glomerulus and is primarily ____ epithelium, a basement membrane, and is associated with specialized branching cells called_____. (J.M.M)
Juxtaglomerular cellS. JG. renin
_____=smooth muscle cells that act as mechanoreceptors that sense blood pressure in the afferent arteriole. ___ cells secrete ____ in response to low blood pressure.
Macula densa cells, vasodilation, vasoconstriction
______=osomoreceptors that respond to solute concentrations in the filtrate and filtrate flow. Low osmolality (slow flow) stimulates _____. High osmolaltiy (fast flow) stimulates _____.
______=possess phagocytic and contractile abilities to influence the total surface area available for filtration
Proximal, brush-border cuboidal
____ convoluted tubules with walls of _______ epithelium for absorption and secretion are located in the renal cortex
Loop of Henle, medulla
_____ with ascending and descending ends and a thick segment of cuboidal and low columnar and a thin segment of simple squamous are located in the _____.
Distal, non-ciliated cuboidal
_____ convoluted tubules with walls of ________ epithelium are more involved in secretion rather than absorption
Juxtamedullarey, medulla, vasa recta
______ nephrons have loops of Henle that deeply invade the ____. These are associated with ____ and the production of concentrated urine.
The production of urine involves three main processes:
1. Glomerular Non-selective filtration occurs at the glomerulus and Bowman's capsule.
2. Tubular reabsorption occurs in the proximal convoluted tubule (PCT), the loop of Henle, and the first part of the distal convoluted tubule (DCT).
3. Tubular secretion occurs mostly in DCT
Glomerular Filtration Rate
_____ is the amount of filtrate formed in both kidneys per minute. In a healthy individual the kidneys produce about 125 ml of filtrate per minute. The majority of this (124 ml) is reabsorbed in the renal tubule portion of the nephron. Therefore, only about 1 ml of urine is produce for each 125 ml of glomerular filtrate.
As the glomerular filtrate enters the PCT, the loop of Henle, and the first part of the DCT, water, ions and other substances are reabsorbed into the blood via the second capillary bed called the ____ capillary bed.
Antidiuretic hormone (ADH)
_____plays a role in water reabsorption at the collection ducts. Increased ___=increased water reabsorption which in turn means less urine is produced. The increase in water retention causes and increase in blood volume which in turn causes blood pressure to increase.
____ promotes the ____ of sodium ions (Na+) and the secretion of potassium ions (K+) within the renal tubules. For example: Low sodium concentration causes suprarenal cortex to increase secretion of _____. This excites tubular cells resulting in sodium transport into capillaries. Because water follows sodium, water reabsorption occurs which causes blood pressure to rise.
Atrial natriuretic peptide (ANP), aldosterone, Na+, K+. ANP
______is a hormone that inhibits the secretion of _____ therefore promoting the excretion of __ and ultimately the reabsorption of ___ Remember that "water follows sodium" so if sodium is excreted, more water will be lost via urine. Therefore, __ acts as a diuretic.
Renin, decreases, renin, vasoconstrictor
(recall from blood studies) and Angiotensin II=___ release is triggered by a drop in blood pressure causing Angiotensin II development (a potent _____). Angiotensin II _____ the glomerular filtration rate which in turn raises blood volume which in turn raises blood pressure.
=production of large quantities of urine resulting in dehydration and intense thirst. Occurs as a result of low ADH release
=an inherited condition that results in urine-filled cysts (or a chloride-rich fluid) forming within the kidney
=developmental disorder resulting in the two kidneys being very close together or joined. (1 in 600 people).
____ occurs in the proximal convoluted tubule (PCT), the loop of Henle, and the first part of the distal convoluted tubule (DCT).
1. Unfiltered blood in the afferent arterioles enters the glomerulus.
2. Recall NFP, or Net Filtration Pressure, from chapter 19. Because hydrostatic pressure is high inside the glomerulus, filtrate is forced out of the blood plasma and into the Bowman's capsule.
3. Pretty much everything (except for blood cells and plasma proteins) is forced into the Bowman's capsule as the filtrate.
4. Efferent arterioles transport filtered blood away from the glomerulus towards the next capillary bed.
5. NOTE: the glomerulus is a unique capillary bed because arterioles move blood into the capillary bed and transport blood away from the capillary bed! Almost all other capillary beds in the body have venules taking blood away from the capillary bed!!!
6. Glomerular Filtration Rate (GFR) is the amount of filtrate formed in both kidneys per minute. In a healthy individual the kidneys produce about 125 ml of filtrate per minute. The majority of this (124 ml) is reabsorbed in the renal tubule portion of the nephron. Therefore, only about 1 ml of urine is produce for each 125 ml of glomerular filtrate.
1. As the glomerular filtrate enters the PCT, the loop of Henle, and the first part of the DCT, water, ions and other substances are reabsorbed into the blood via the second capillary bed called the peritubular capillary bed.
2. Na+ is moved out of the tubule and into the blood by facilitated diffusion whereas glucose, amino acids, lactic acid, vitamins, and most cations are reabsorbed by secondary active transport.
3. Some substances (K+ and anions like Cl-) move through the intercellular spaces to leave the tubules to the interstitial spaces and then simply diffuse into the bloodstream.
4. Most other substances (urea, fat-soluble vitamins, and some drugs) simply diffuse from the tubule lumen directly into the capillary bed.
5. Again about 98-99% of all filtrate is reabsorbed. See Table 25.1 on page 1013.
1. The remaining fluid that enters the rest of the distal convoluted tubule is not quite complete.
2. Tubular secretion involves the movement of substances out of blood (peritubular capillary bed) and back into the remaining filtrate.
3. Some substances move by active transport while others move by passive transport
4. Substances commonly secreted include potassium ions, hydrogen ions, ammonia ions, by products of drugs and penicillin, creatinine, and some hormones.
5. The final fluid that now drains from the DCT and into the collection ducts is called urine.
6. The collection ducts drain into the renal pelvis which is connected to the tops of the ureters which undergo peristalsis to transport urine to the bladder for storage.
Substances that are NOT reabsorbed easily!
Creatinine (which is secreted rather than filtered).
1. 90% water
2. Metabolic or nitrogenous wastes (urea, creatinine, uric acid)
5. Pigments such are urochrome (breakdown of hemoglobin and bile pigments)
7. If blood, protein, or glucose are detected in urine this is usually an indication of kidney troubles.
1. Color=clear, deep yellow in color
2. Odor=slightly aromatic when fresh but tends to develop and ammonia odor due to bacterial metabolism
3. pH=urine is slightly acidic (about pH 6)
4. Specific gravity=1.001 to 1.035