1.Describe the functions of the kidney
- Regulation of composition of ions in the blood (Na+, Cl-, Ca2+, HPO42-,K+)
- Blood pH regulation via H+ and HCO3-
- Blood volume regulation by water excretion or reabsorption
- Blood pressure regulation via renin secretion
- Hormone production (Active form of Vitamin D= Calcitriol, Erythropoietin)
- Blood glucose regulation by gluconeogenesis (formation of glucose from amino acid glutamine)
- Waste and foreign material excretion (creatinine, urea, ammonia, bilirubin, uric acid, drugs, environmental toxins)
2.Describe the sequence of structures through which a drop of urine passes from the time it flows from the nephron until it reaches the urinary bladder.
- Collecting duct
- Papillary duct
- Minor Calyx
- Major Calyx
- Renal Pelvis
- Urinary bladder
3.Describe the sequence of structures through which a drop of blood passes from the time it flows from the renal artery into the kidney until it reaches the renal vein.
- Renal artery
- segmental arteries
- interlobar arteries
- arcuate arteries
- interlobular arteries
- afferent arterioles
- glomerular capillaries
- efferent arterioles
- Peritubular capillaries
- interlobular veins
- arcuate veins
- interlobar veins
- renal vein
4.Describe the sequence of structures through which a drop of fluid passes from the time it flows from the glomerulus until it reaches the collecting duct.
- Glomerular (Bowman's) capsule
- Proximal convulated tubule
- Descending limb of Henle
- Ascending limb of the loop of Henle
- Distal convulated tubule( drains into collecting duct)
5.Describe the juxtaglomerular apparatus.
- Macula densa (Simple cuboidal epithelial cells of the ascending loop of Henle in contact with the afferent arteriole)
- Juxtaglomerular cells (modified smooth muscle fibers of the afferent arteriole)Together the juxtaglomerular apparatus regulates the blood pressure.
6.Describe the three basic processes that produce urine.
- Glomerular filtration: The movement of the water and solutes from the blood plasma across the glomerular capillary endothelium into the glomerular capsule and renal tubule (proximal)
- Tubular reabsorption: Return of most of the water and the solutes from the renal tubule into the blood in the peritubular capillaries and vasa recta.
- Tubular secretion: Movement of substances from the blood in the peritubular capillaries or from the tubular or duct cells into the renal tubule.
7.Summarize glomerular filtration by:Explaining why the glomerulus is able to filter a greater volume of fluid than capillaries elsewhere in the body:
- 1. Large surface area of the glomerulus,
- 2. Large fenestrations in the endothelium,
- 3. Blood pressure in the glomerulus is higher than in the capillaries in the rest of the body
7.Summarize glomerular filtration by: Defining glomerular filtration rate:
amount of filtrate formed in all renal corpuscles of both kidneys per minute
7.Summarize glomerular filtration by: Summarizing renal autoregulation of glomerular filtration rate:
- Although blood pressure goes up and down, renal autoregulation keeps glomerular filtration rate constant. In other words, the same amount of fluid usually is filtered out of the blood no matter what the blood pressure. 2 processes work together to make this happen.
- Process 1: As blood pressure rises, the walls of afferent arterioles are stretched, which makes the afferent arterioles constrict, lowering the glomerular filtration rate. As blood pressure lowers, the walls of afferent arterioles relax, which makes the afferent arterioles dilate, raising the glomerular filtration rate.
- Process 2: As blood pressure rises, the macula densa stop the juxtaglomerular cells from releasing nitric oxide, the afferent arterioles constrict, lowering the glomerular filtration rate. As blood pressure lowers, the macula densa shut down, the juxtaglomerular cells release nitric oxide, which makes the afferent arterioles dilate, raising the glomerular filtration rate.
8.Define renal calculi and state their common name.
Xalcium oxalate, uric acid and calcium phosphate crystals present in urine get deposited and solidified in the kidneys forming renal calculi commonly called renal stones or kidney stones.
9.Summarize regulation of tubular reabsorption by: Stating the function of the juxtaglomerular cells:
constitutes juxtaglomerular apparatus with macula densa
9.Summarize regulation of tubular reabsorption by: Explaining how the renin-angiotensin-aldosterone system influences tubular reabsorption of water and regulates blood pressure
- When blood pressure is LOW: juxtaglomerular cells release renin to activate the renin-angiotensin-aldosterone system water levels in the blood increase, which raises blood pressure.
- When blood pressure is HIGH: Macula densa inhibits the juxtaglomerular cells from releasing renin Turning off the renin-angiotensin-aldosterone system which lowers blood pressure.
9.Summarize regulation of tubular reabsorption by: Describing how antidiuretic hormone influences tubular reabsorption of water:
the ADH influences the permeability of the convoluted tubules, this will help the water and nutrients be reabsorbed into the cells and into the blood stream
9.Summarize regulation of tubular reabsorption by: Relating diabetes insipidus with antidiuretic hormone and urine output:
lack of ADH, water is not reabsorbed and as a result, large volume of urine is excreted
10.Explain the: Formation of dilute urine:
- H2O reabsorbed in descending loop of Henle resulting in more concentrated tubular fluid. Ascending Loop of Henle reabsorbs more solutes but not water, resulting in progressively dilute tubular fluid this continues in distal convoluted tubule further diluting tubular fluid. Absence of ADH makes collecting ducts impermeable to water but allows absorption of solutes leaving increasingly diluted tubular fluid to drain into the renal pelvis.
- The osmotic gradient that attracts water out of the collecting ducts is created by the salt concentration in the kidney medulla. It is high there because of reabsorbed Na+ ions combined with Cl- to form NaCl. Water is pulled from the filtrate to dilute the high salt side.
10.Explain the: Formation of concentrated urine:
symporters in thick ascending limb establish osmotic gradient; principal cells in collecting duct reabsorb more water when ADH is present; urea recycling causes buildup in renal medulla.
10.Explain the: Related function of antidiuretic hormone:
The convoluted tubules are impermeable to water when antidiuretic hormone is absent or low. So, low ADH results in diluted urine and high ADH results in concentrated urine.
Substances that causes diuresis or increased flow of urine by decreasing the renal absorption of water.
11.Explain the mechanism of alcohol and caffeine as diuretics.
- caffeine - inhibits the absorption of Na+
- alcohol - inhibits ADH secretion
11.Summarize the mechanism of dialysis:
The procedure to cleanse blood artificially. It is the separation of large solutes from smaller ones by diffusion through a selectively permeable membrane.
12.Describe the function of transitional epithelium and name the urinary system organs lined with this tissue:
Transitional epithelium lines the urinary bladder and ureters.It has the ability to stretch which enables the ureters and bladdar to change its size thus enabling them to accomodate varying volumes of urine.
13.Describe the location and function of the internal and external urethral sphincters:
Around the opening to the urethra the muscularis forms an internal urethral sphincter. Inferior to the urethral internal sphincter is the external urethral sphincter.
discharge of urine fron urinary bladder into urethra
13.Describe the micturition reflex
- Increased pressure inside the bladder due to the increased volume stretch receptors send impulses to spinal cord (sacral region)
- parasympathetic impulses from the spinal cord to the detrusor muscle of the bladder, causing contraction of the smooth muscle and relaxation of the internal urethral sphincter spinal cord inhibits somatic motor neurons to the skeletal muscle of the external urethral sphincter, relaxing it.
14.Explain why urinary tract infections are more common in females - in females, the urethra is much closer to the anus and is shorter than in males; women also lack prostatic secretions
- Define cystitis.---->Inflammation of the urinary bladder.
- Define pyelonephritis - inflammation of the kidney and upper urinary tract that usually results from noncontagious bacterial infection of the bladder (cystitis).
15.Define urinary incontinence:
Inability over voluntary control of urination.
16.Define urinary retention:
Inability to completely empty the bladder (despite the urge to urinate.)
17.Define acid-base balance.
a homeostatic challenge for the kidney to keep pH level of body fluids in the appropriate range (neither basic or acidic), so that the body can function normally. KISS: a homeostatic mechanisms to keep pH level of body fluids in the appropriate range (between 7.35 and 7.45).
17.Summarize how the urinary system helps regulate acid-base balance.
- The Urinary system helps regulate acid-base balance by the removal of H+ from body fluids and subsequent elimination from the body via three major mechanisms:
- buffer systems.
- excretion of H+ in urine.
- exhalation of carbon ioxide.
18.Define specific gravity as it relates to urine.
the concentration of solutes in urine, usually measured by comparing the weight of urine to distilled water.
18.State the clinical significance of a urinalysis indicating: Cloudy urine
Precence of microbes, pus
18.State the clinical significance of a urinalysis indicating: Low or high pH:
- this test it reflects the acidity or alkalinity of the urine.
- high pH indicates high protein diet(acidic urine)
- low pH indicates a low protein diet like vegetarian diets(alkaline urine).
18.State the clinical significance of a urinalysis indicating: Low or high specific gravity
- Low specific gravity: dehydration or glucosuria.
- High specific gravity: diebetes insipidus, kidney infection, kindey failure
18.State the clinical significance of a urinalysis indicating: Glucosuria
Glucose in the urine, due to a high blood concentration of glucose. Most common cause is diabetes mellitus.
18.State the clinical significance of a urinalysis indicating: Hematuria:
Presence of RBC in the urine, could be due to a damage to the glomerular filtration membrane allowing large items such as RBC to pass through (pyelonephritis), in cystitis or urethritis-damage to the epithelium caused by a inflammation or infection
18.State the clinical significance of a urinalysis indicating: Albuminuria
high amounts of albumin in urine, caused by high blood pressure, kidney trauma, disease or inflammation
18.State the clinical significance of a urinalysis indicating: Ketonuria
Caused by metabolic condition called ketosis for lack of enough glucose to break down the fatty acid
19.State the function of the Kidney:
regulation of blood ionic composition, blood pH, blood volume, blood pressure, production of hormones, blood glucose, excretion of waste/foreign substance.
19.State the function of the Renal cortex:
it is the smooth-textured area extending from the renal capsule to the bases of the renal pyramids and into the spaces between them.
19.State the function of the Renal medulla:
19.State the function of the Renal pyramid
19.State the function of the Collecting duct
19.State the function of the Renal papilla
Drains urine to the minor calyx.
19.State the function of the Minor calyx
it receives urine from the papillary ducts of renal papilla and delivers it to the major calyx
19.State the function of the Major calyx
Receives urine from papillary ducts.
19.State the function of the Renal pelvis:
acts as funnel for urine flowing to ureter
19.State the function of the Renal hilum
it is an indentation through which the ureter leaves the kidney, and blood vessels, lymphatic vessels, and nerves enter and exit.
19.State the function of the Nephron
Functional unit of the kidney.
19.State the function of the Glomerulus
a capillary network used to carry plasma to the renal corpuscle for filtration
19.State the function of the Glomerular capsule
filters plasma from glomerulus and transports it to the renal tubule
19.State the function of the Renal tubule
where the filter fluid from the renal corpuscle passes though and consist of the proximal convoluted tubule, loop of henle, and the distal convoluted tube
19.State the function of the Proximal convoluted tubule
connects from the glomerular capsule
19.State the function of the Loop of Henle
Reabsorption into blood of: H2O, Na+, K+, Cl-, HCO3-, Ca2+, Mg2+. Secretion into urine of Urea. At end of loop of Henle, tubular fluid is hypotonic.
19.State the function of the Distal convoluted tubule
Reabsorption into blood of: H2O, Na+, Cl-, Ca2+ and Urea. Secretion into urine of K+ and H+. Tubular fluid leaving the collecting duct is dilute when ADH level is low and concentrated when ADH level is high.
19.State the function of the Segmental artery
19.State the function of the Interlobar artery
19.State the function of the Arcuate artery
19.State the function of the Interlobular artery
19.State the function of the Afferent arteriole:
Carries blood in the glomerulus
19.State the function of the Efferent arteriole:
carriess blood out of the glomerulus
19.State the function of the Peritubular capillary
receives blood from Efferent arteriole.
19.State the function of the Interlobular vein:
Receive blood from vasa recta.
19.State the function of the Arcuate vein
Blood drains through from vasa recta
19.State the function of the Interlobar vein
Blood runs between the renal pyramids.
19.State the function of the Ureters:
it transport urine to the urinary bladder.
19.State the function of the Urinary bladder
it stores and release urine
19.State the function of the Detrusor muscle
contracts to squeeze urine out and relaxes to fill the urinary bladder
19.State the function of the Trigone
triangle region of the bladder base, consisting of the two ureteric orifices and urethra
19.State the function of the Rugae:
folds in the mucosa and allows of the urinary bladder to expand
19.State the function of the Urethra:
small tube leading from the urinary bladder to the exterior of the body. In males, it allows for semen discharge