Urinalysis

factors the impact urine color

diet, drugs, and disease

Light yellow to amber

normal urine color

clear to light yellow

due to increased fluid intake, alcohol, or diabetes

yellow-orange to orange color

due to carrots, antibiotics, pyridium or bilirubin (broken down red blood cells) from jaundice

green

due to green food dyes, asparagus, diuretics, or bacterial infection

red to red brown

due to beets, senna laxatives, or hemoglobin in urine (various causes)

brown

due to rhubarb, fava beans, severe dehydration, barbiturates, hemolytic anemia, strenuous muscle activity

brown-black

due to rhubarb, sorbitol, antidepressants, melanoma

normal urine pH

6-7

normal specific gravity of urine

1.010-1.026

normal protein in urine

absent

normal glucose in urine

absent

low pH of urine

Under 5

due to high protein diet, cranberry juice or diabetes mellitus

high pH of urine

Over 8

anemia, diet rich in veggies and dairy

high specific gravity of urine

Over 1.026, Concentrated with solutes

dehydration, anemia, diabetes mellitus

low specific gravity of urine

Under 1.010, diluted

increased fluid intake, renal damage

glucose present

due to large meal or diabetes mellitus

protein present

high protein diet or anemia

hydrometer

An instrument for determining the density of solids and liquids by flotation.

refractometer

Instrument that measures specific gravity, uses refraction of light

the amount of water and salts in the body is determined by

a balance of gains and loss

how is water gained in the body

ingestion and metabolic production

how are salts gained in the body

ingestion

how can water be lost

feces, urine, evaporation (sweat or insensible loss)

how can salt be lost

feces, urine, and evaporation

What is the most important mechanism for moderating gains and losses

urinary excretion

If the body is well hydrated...

ingestion of more water will lead to increased water loss in the urine

decreasing osmolarity -> triggering osmoreceptors in the hypothalamus -> inhibit secretion of ADH -> reducing water reabsorption -> larger volume of more dilute urine

if the body is in sodium balance...

ingestion of sodium will lead to more Na+ loss in the urine

increase in Na+ -> increase in ECF volume due to osmosis and concentration gradient -> decrease aldosterone secretion -> increase GFR -> decrease in ADH secretion -> increase atrial natriuretic peptide-> decrease reabsorption of salt by nephrons

Andtidiuretic Hormone (ADH)

causes kidneys to release less urine and increase water retention

secreted when the concentration of solutes in the blood plasma fluid is high

released from the posterior pituitary.

increases permeability in the collecting duct of the nephron

aldosterone

"salt-retaining hormone" which promotes the retention of Na+ by the kidneys. na+ retention promotes water retention, which promotes a higher blood volume and pressure, releases potassium

Osmolarity if ingestion of water and salt = isotonic NaCl

more water and salt excretion due to increase ECF volume

lowers ADH production

Osmolarity if ingestion of water and salt = hypertonic saline

less water and salt excretion due to decrease ECF volume

raises ADH production

functions of the kidneys

Remove waste products from blood; Assist in regulation of blood volume & blood pressure, ion levels, & blood pH.

kidney acid/base balance

Kidneys control acid-base balance by regenerating bicarbonate, excreting H+ when blood becomes too acidic and excreted bicarbonate when blood becomes too alkaline

turbidity

A measure of how clear water is.

cloudy urine indicates bacterial infection

ketones

Ketones are compounds produced in the body during fatty acid metabolism. Ketones can easily pass through the filtration membrane of the nephron and are not normally found in urine. The presence of ketones may indicate disease, such as diabetes.

urine dipstick test

test that measures glucose, ketones, and other substances in the urine

Color changes of the individual pads are compared to a standard.

each kidney filters

1 liter of blood per minute

nephron

functional unit of the kidney that forms urine, each has a renal corpuscle and a renal tubule

proximal convoluted tubule

Absorbs 80% of filtrate, including water, glucose, and amino acids

first section of the renal tubule that the blood flows through; reabsorption of water, ions, and all organic nutrients

Distal Tubule

Increases osmolarity of medulla; absorbs water.

glomerulus

small network of capillaries encased in the upper end of a nephron; where the filtration of blood takes place

descending limb of nephron loop

Permeability controlled by hormones; can absorb additional sodium and water.

Bowman's capsule (renal corpuscle)

receives filtrate from glomerulus

The glomerulus is a capillary bed where

high blood pressure forces blood plasma and small solutes into the space of the glomerular capsule. This fluid is called filtrate.

Tomato Juice Drinker Phils lab

More water reabsorbed due to salt content being similar to blood plasma

Soda Drinker Phils Lab

had the highest volume of urine across the experiment, paired with consistently low sodium because there was no sodium in the soda, had a higher pH because water stayed in the collecting duct to balance out the few amounts of solutes in the blood

leukocytes or red blood cells in urine

not normally in urine, both indicate some type of infection

often UTI or kidney related

What is normally found in urine

Salts (Na+, K+, CI)

Nitrogenous waste (Urea, uric acid, creatinine)

Water

What is NOT normally found in urine?

glucose, proteins, leukocytes, blood