Lab Quiz 7 Flashcards
how kidneys achieve homeostasis
regulating the pH and concentration of ions and water in the body fluids
additional role of kidneys
eliminate the waste products of metabolism
number of nephrons in the kidneys
1 million
two structures of the nephrons
renal corpuscle and renal tubule
tuft of capillaries in the renal corpuscle where blood first filters through
glomerulus
rate at which blood filters through glomerulus
120 ml/min
three major parts of the renal tubule
proximal convoluted tubule (PCT)
nephron loop (Loop of Henle)
distal convoluted tubule (DCT)
similar to blood plasma in composition but large molecules are excluded
tubular filtrate
MW of molecules too large for filtrate
70,000 MW
example of molecules too large to pass through filtrate
plasma proteins
retained in the filtrate and finally excreted in the urine
toxic by-products of metabolism and excess substances
how much urine is formed per minute
1 ml of urine / min
reflects the integrity of kidney function and changes in blood composition
the final composition of urine
analysis of urine; yields valuable information about the health of the kidney and the body in general
urinalysis
phenylketonuria (PKU)
-genetically unable to metabolize the amino acid phenylalanine
phenylalanine becomes __ if accumulated
phenylpyruvic acid
may result from an accumulation of phenylalanine in individuals with PKU
developmental delays, seizures, intellectual impairments
diabetes mellitus (diabetes)
imbalance or deficit in the amount of insulin produced by the pancreas
fatty acid metabolites that result from the body using fat as an energy source instead of sugars
ketones
causes blood pH to decrease
increase in ketones
indicated by the presence of glucose and ketones in the urine, combined with a low pH
diabetes mellitus indication
Labstix test
combined test of urinary pH, protein, glucose, ketones, and occult blood
normal pH of urine
slightly acidic, ~6
causes more acidic urine
diet rich in proteins, respiratory disorders, dehydration, starvation
causes more alkaline urine
diet rich in citrus fruits and dairy, vomiting, urinary tract infections, or cystitis
cystitis
urine decomposes in the bladder with the production of ammonia
proteinuria or albuminuria
-presence of proteins in the urine
-indicates that the “filters,” or glomeruli of nephrons are damaged, allowing blood proteins into the filtrate
glycosuria
-high levels of glucose in the urine
-indicates the body’s inability to process glucose
-leads to accumulation of glucose in the blood that is secreted in the urine
ketonuria
-abnormally large amounts of ketone excretion
-can indicate wither diabetes mellitus or starvation
blood not visible to the naked eye
occult blood
indicated by occult blood in the urine
structural damage in the urinary tract- urinary tract infection, kidney stones, cancerous cells
nephritis
-disease in which the glomeruli are damaged and plasma proteins and erythrocytes leak into the nephrons
-blood and high levels of proteins present in urine
one of the main functions of the kidneys
regulate the osmolarity of the body fluids to ensure cells do not shrink or swell
regulatory osmolarity of body fluids
300 milliosmoles per liter
dehydrated individual
produces small amounts of highly concentrated urine
overhydrated individual
produces a large amount of minimally concentrated (dilute) urine
groups for kidney regulation experiment
Group 1- 800 ml water
Group 2- 800 ml water, 7g NaCl
Group 3- 80 ml water, 7g NaCl
the ratio of the density of a substance compared to the density of distilled water
specific gravity
calibration temperature of urinometer
15°C
how to correct the specific gravity value
add 0.001 for every 3°C above or subtract 0.001 for every 3°C below the calibration temperature
normal range of urine specific gravity
1.0015 to 1.035
specific gravity of distilled water (no solutes present)
1.000
found in individuals with chronic nephritis
low specific gravity
chronic nephritis
slow onset kidney disease
observed in acute nephritis
high specific gravity
acute nephritis
sudden onset kidney disease
Mohr Method (NaCl concentration)
the process of titrating silver nitrate to analyze the presence of chloride ions in a substance using potassium chromate as an indicator
adding one drop in the mohr method
20% potassium chromate
adding drop by drop in the mohr method
2.9% silver nitrate
represents 1g/liter of NaCl present in the urine
each drop of 2.9% silver nitrate
3 plots against time for data collection
ml urine excreted, specific gravity, and NaCl concentration (mg/ml)
