Principle: pH

*double indicator system.

*indicators methyl red and bromthymol blue are used to give distinct color changes from orange to green to blue 

Principle: Protein

*protein error of indicators. 

*÷at a pH of 3, tetrabromphenol blue releases hydrogen ions in the presence of albumin, exchange of H+ between albumin and indicator produce a color change

reagent strip contains: tetrabromphenol blue, buffer

Principle: glucose

*double enzyme reaction

÷oxygen binds to chromogen 

 •reagent strip contains

Principle: Ketones

Principle:Blood

Function and structure of Kidney

-filters blood

-remove waste products

-regulates electrolytes, water acid-base balance and blood pressure.

Fuction and structure of ureters

-fibromuscular tube

-25cm long

-emerges from renal plevis of each kidney and extends down to connect to the base of bladder

*moves urine down into bladder

Function and stucture of bladder

function and structure of urethra

Function of glomerulus

AKA renal capsule

-network of capillaries

-forms barrier that is designed specifically for plasma ultrafiltration

function of bowmans capsule

-cuplike sac at beginning of tubular component of nephron

- performs first step in filtration of blood to form urine

-glomerulus is enclosed in sac

-fluids from blood in glomerulus are collected in bowmans capsule

function of afferent arterioles

-small branch of an interlobular renal artery that becomes the capillary tuft within a glomerulus 

-supplies blood individually to the glomerulus of each nephron

function of efferent arteriole

-arteriole exiting the glomerulus

-formed by rejoining of the anastomosing capillary network within the glomerulus

-bc smaller then afferent arteriole it creates some resistance to blood flow producing the back up of blood in the glomerulus which creates higher pressure in the glomerular cavity

function of proximal convulated tubules

-most proximal segment of renal tubular portion of nephron 

-responsible for reabsorption of glucose, amino acids, and various ions and water

function of distal convulated tubule

-reabsorption of sodium, water and secreation of hydrogen potassium portion of renal nephron

-immediatley after loop of henle

function of loop of henle

-leads from proximal tubule to distal tubule, 

-main function to create a concentraion gradient in the medulla of the kidney 

-responsible for reabsorption

function of collecting duct

-site of final urine concentration

-distal tubules empty into collecting duct terminate at the renal papilla conveying the urine formed into the renal calyxes of the kidney

describe process of filtration

glomerular filtration is unidirectional process that occurs for most small molecules

-blood pressure forces filtrate out of glomerulus into bowmans capsule then into proximal tubule 

1.blood cells protien and other large solutes cannot pass capillary wall into capsule

2.water, glucose, sodium, and urea are forced out

describe process of secreation

 active transport process

-requires energy

-molecules transport against concentrated gradient

-may be saturated 

-moves substances from capillaires into nephron walls

1.capillaries surrounding nephrons secrete excess amounts of H+ ions and potassium ions in the nephron tubules

2.rids body of drugs, uric acid, hemoglobin, breakdown of products and other wastes

describe function of reabsorption

-takes place in tubular parts of nephrons where water and solutes move across the tubular wall out of the nephron

-by diffusion or active transport into cappilaries 

-happends after molecules filtered at glomerulus (active or passive)

-reabsorption of acids or weak basis influenced by pH of urine and pKa of molecules

-urine pH and pKa determine % of ionized and unionized

ADH produced in hypothalamus transfered by posterior pituatary.

-when increase in arterial blood pressure accurs, hypothalamus signaled and inturn inhibits release of ADH. -as plasma level of ADH decreases the collecting tubule epithelium changes and osmosis of water from the lumen also decreases=more dilute urine (more water excreted)

HAPPENS VICE VERSA TOO!

Action and regulation of Renin

produced by cells of juxtaglomerular apparatus of renal nephrons

-secration of renin =formation of angiostensin and aldosterone

-when released into bloodstream in repsonse to decreased blood volume, decreased arterial pressure, sodium depletion, vascular hemmorrhage or increased potassium forms angiotensin and causes secretion of aldosterone

Action and regulation of aldosterone

stimulates kidney activity to retain sodium and passively retain water

-so the volume of fluid expands, blood pressure increases and normal potassium levels as well as normal renal perfusion are restored

Large amount of foam in urine indicates?

 increase concentration of protein

Specific gravity measures amount of dissolved substances in a solution.

refractive index is the ratio of velocity of light in are to velocity of light in solution 

(ratio varies with dissolved particles in solution)

osmolality measurement of property of soln related to the # of molecules of solute per kilogram of solvent =amount of stuff dissolved

ALL MEASURE URINE CONCENTRATION

Normal Urine volume should be

Polyuria

abnormally large amount of urine

over 2000 mL/24hrs

Oliguria

small amount of urine 

less than 500mL/24hrs

Anuria

Practical analytical sensitivity of pH

5.0-9.0

Practical analytical sensitivity of protein

15-30 mg/dL

Practical analytical sensitivity of glucose

75-125 mg/dL

Practical analytical sensitivity of ketone

10 mg/dL of acetoacetic acid

Practical analytical sensitivity of blood

5-10 erythrocytes/uL

0.015 mg/dL hemoglobin?

Specificity of pH

Specificity of ketones

Specificity for blood

Specificity for glucose

glucose

Specificity for protein

albumin

False positive/ Neg for ketones

False + = high pigmented urines, large amounts of levodpar metabolites

False - =improper storage =bacterial breakdown

False positive/ Neg for blood

False + = menstral contam., microbial peroxidase, strong oxidizing agents (soaps, detergent..)

False - =ascorbic acid, high specific gravity, captopril

False positive/ Neg for glucose

 false + = strong oxidizing agents, peroxide contaminiation 

False - = ascorbic acid, ketones, improper strored specimens

False positive/ Neg for protein

 False + = highly buffered urine or alkaline urines, drugs (highly colored substances)

False - = colored substances (drugs), beet ingestion