Anatomy 2 Lab Practical #2 Stuff

Table for normal values for different substances found in urine

How do kidneys achieve homestasis?

by regulating the pH and concentration of ions and water in the various body fluids; elimination of waste products of metabolism

How many nephrons in the kidneys contain two main structures?

1 million nephrons

What are the 2 structures the one million nephrons in the kidneys contain?

renal corpuscle & renal tubule

Where is blood first filtered through?

a tuft of capillaries called glomerulus

What is the rate that blood passes through the tuft of capillaries (glomerulus)?

120 mL/min

What are the 3 major parts of the renal tubule?

proximal convoluted tubule (PCT), nephron loop (Loop of Henle), and the distal convoluted tubule (DCT)

The tubular filtrate similar to blood plasma in composition, except large molecules over what are excluded?

70,000 MW (e.g., plasma proteins)

What by-products are retained in the filtrated and are finally exerted in the urine?

toxic by-product of metabolism and excess substances (salt)

How much urine is formed per minute?

1 mL of urine formed per minute

What does the final composition of urine reflect?

reflects the integrity of kidney function and changes in blood composition

Urinalysis

an analysis of urine that can yield valuable information about the health of the kidney and of the body in general

Phenylketonuria (PKU)

when an individual is genetically unable to metabolize the amino acid phenylalanine

What is phenylalanine converted into when accumulated in the body?

phenylpyruvic acid

What can an accumulation of phenylalanine in individuals with PKU result in?

developmental delays, seizures, and intellectual impairments

Diabetes Mellitus (diabetes)

when an individual has either an imbalance or a deficit in the amount of insulin produced by the pancreas

Ketones

when the sugars in the blood cannot be used as cellular fuel, the body will utliize fat as an energy source, leading to an increase in fatty acid metabolites called this

What will an increase in ketones do to blood pH?

cause it to decrease

What is indicative of diabetes mellitus?

presence of both glucose and ketones in the urine

Labstix Test

a combined test of urinary pH, protein, glucose, ketones, and occult blood

What is the Urinary pH?

pH of 6

What can a more acidic urine mean?

diet rich in proteins or respiratory disorders, dehydration, or starvation

What can a more alkaline urine mean?

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

the presence of protein in the urine

Glycosuria

high glucose levels in urine, which indicate the body’s inability to process glucose, leading to an accumulation of glucose in the blood that is then secreted in the urine

Ketonuria

abnormally large amounts of ketone excretion, suggest that the body is using fat as an energy source as opposed to glucose

What can ketonuria indicate?

diabetes mellitus or starvation

What can glycosuria indicate?

diabetes mellitus

Occult Blood

blood not visible to the naked eye

What can blood present in the urine indicate?

an individual has a urinary tract infection, kidney stones, or cancerous cells

Nephritis

a disease in which the glomeruli are damaged and plasma proteins and erythrocytes leak into the nephrons (blood present in urine and high levels of protein)

When should you examine the strip?

examine BEFORE conducting the test so you know which portions to read first.

How many seconds should you wait to read the glucose test portion?

10 seconds

How many seconds should you wait to read the ketone portion?

5 more seconds

How many seconds should you wait to read the occult portion?

15 more seconds

What is one of the kidney’s main functions?

to regulate the osmolarity of the body fluids

At what rate do the kidneys regulate the osmolarity of the body fluids?

300 milliosmoles per L

What happens to the concentration of urine for someone who is dehydrated?

will produce a SMALL amount of highly concentrated urine

What happens to the concentration of urine for someone who is overhydrated?

will produce a LARGE amount of minimally concentrated (dilute) urine

What are Group 1’s consumed fluid solute concentrations?

800 mL water

What are Group 2’s consumed fluid solute concentrations?

800 mL water with 7 g NaCl

What are Group 3’s consumed fluid solute concentrations?

80 mL water with 7 g NaCl

Specific Gravity

the rate of the density of a substance compared to the density of distilled water

Should you drop the urinometer float directly into the cylinder?

do NOT drop the urinometer float directly into the cylinder

What calibration temperature for the urinometer?

15^oC

How will you correct the specific gravity value?

by adding 0.001 for every 3^oC above, or by subtracting 0.001 for every 3^oC below the calibration temperature (15^oC)

What is the normal range of urine specific gravity?

1.0015 to 1.035

What is the specific gravity of distilled water?

1.000

Chronic Nephritis

a low specific gravity reading in individuals (slow, onset kidney disease)

Acute Nephritis

a high specific gravity in individuals (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

How many drops of 20% potassium chromate do you add to the test tube?

ONE drop

How do you add 2.9% silver nitrate solution?

DROP by DROP

How much NaCl does each drop of 2.9% silver nitrate represent?

1 g/L of NaCl

How many separate plots for your data should you make?

3 separate plots

Chronic Obstructive Pulmonary Disorder (COPD)

obstruction of the lungs causes air to be “trapped” in the lungs when it cannot be exhaled

• over time → causes stretching of the lung tissue

Tidal Volume (TV)

the amount of air inhaled or exhaled on a normal breath

Inspiratory Reserve Volume (IRV)

the additional air that can be forcefully inhaled past a normal tidal volume inspiration

Expiratory Reserve Volume (ERV)

the additional air that can be forcefully exhaled past a normal tidal volume expiration

Residue/Residual Volume (RV)

the volume of air remaining in the lungs following a maximal exhalation

Vital Capacity (VC)

the total amount of air that can be forcefully expired after a maximum inhalation

Vital Capacity (VC) Equation

VC = TV + IRV + ERV

• vital capacity = tidal volume + inspiratory reserve volume + expiratory reserve volume

Inspiratory Capacity (IC)

the maximum amount of air that can be inspired after a normal inhalation

Inspiratory Capacity (IC) Equation

IC = TV + IRV

• inspiratory capacity = tidal volume + inspiratory reserve volume

Functional Residual Capacity (FRC)

the total amount of air remaining in the lungs after a normal exhalation

Functional Residual Capacity (FRC) Equation

FRC = RV + ERV

• functional residual capacity = reserve/residual volume + expiratory reserve volume

Total Lung Capacity (TLC)

the total amount of air the lungs can contain

Total Lung Capacity (TLC) Equation

TLC = TV + IRV + ERV + RV

• total lung capacity = tidal volume + inspiratory reserve volume + expiratory reserve volume + reserve/residual volume

Spirometry

a medical test used to measure the four lung volumes with the use of a simple, non-invasive instrument (spirometer)

Spirometer

non-invasive instrument used during spirometry

Respiratory Minute Volume (mL air/min)

total amount of air that flows into and out of the respiratory tract in 1 minute

Respiratory Minute Volume (mL/min) Equation

Vital Capacity

the largest volume found during vital capacity

Predicted Vital Capacity

the vital capacity predicted with the use of a nomogram

What does a longer breath-holding indicate?

indicated better pulmonary function, functional reserve, and larger lung capacity because the lungs are better able to help maintain the body pH

What are the functions of the respiratory system and cardiovascular system?

function to take oxygen into the body from the atmospheric air and deliver it to the tissue cells

Respiratory Acidosis

condition indicated by carbon dioxide build up in the blood, the pH of the blood becomes more acidic

Dry Gas Meter

measures tidal volume by breathing into a mouthpiece and Douglas bag connected to the dry gas meter, and measuring the volume of air stored in the bag

Minute Volume (V_m)

calculated by multiplying the total volume of air exhaled (mL) by the number of breaths taken over the collection period (minutes)

• the flow of air into and out of the lungs

Metabolic Rate

dry gas meter measures this; is the body’s rate of energy expenditure

What is the percentage of oxygen in inhaled air?

20.95%

How is metabolic rate calculated?

the difference between the percentage of oxygen in inhaled air (20.95%) and the percentage of oxygen in the exhaled air stored in the bag → and multiplying this difference by the minute volume (V_m)

Is the metabolic rate of skeletal muscle tissue cells higher or lower during physical activity?

metabolic rate of skeletal muscle tissue cells is significantly higher, requiring more oxygen uptake and delivery to the cells

Respiratory Capacities Graph

Rate of Oxygen Consumption (V_O2)

equal to both the rate at which you obtain oxygen from the environment across the surface of the lungs (i.e., ventilation) and the rate at which oxygen is delivered to body tissue cells through the capillary walls (i.e., perfusion) of the cardiovascular system

Ventilation-Perfusion Coupling

the balance in exchange between the oxygen you obtain from the environment across the surface of the surface of the lungs and the oxygen delivered to body tissue cells through capillary walls (rate of oxygen consumption [V_O2])

How is Ventilation increased?

ventilation is increased by increasing the respiratory rate and respiratory depth (tidal volume)

How is Perfusion increased?

perfusion is increased by increasing heart rate

What is the flow of blood related to in the cardiovascular system?

related to Cardiac Output (CO)

What leads to a difference in the concentration of oxygen in inhaled air (C_O2i) and the concentration of oxygen in exhaled air (C_O2e)?

lungs extracting oxygen from the air we breathe

What leads to a difference in the concentration of oxygen in arterial blood (C_O2a) and the concentration of oxygen in venous blood (C_O2v)?

oxygen is lost from the blood supply through the capillary beds in systemic circulation

V_O2 Equation

V_O2 = (minute volume) (concentration of oxygen in inhaled air - concentration of oxygen in exhaled air)

How saturated is arterial blood and venous blood in most resting people?

Arterial Blood Saturation = 100%

Venous Blood Saturation = 60%

How much oxygen can 1 gram of hemoglobin bind to?

1.34 mL of O₂

Maximum Oxygen Content Equation

Oxygen Content of Venous Blood Equation

C_O2v = 0.6 (maximum oxygen content)

Resting Cardiac Output Equation

CO = rate of oxygen consumption / (maximum oxygen content - oxygen content of venous blood)

Resting Stroke Volume (SV) Equation

SV = resting cardiac output / heart rate

What happens to oxygen content of the venous blood during exercise?

oxygen content of venous blood falls due to increased oxygen demands by the body cells