Chemistry Exam 3 Flashcards by Ngoc Nguyen

Primary concern with medical, legal consequences of exposure.
Major focus: generate evidence

Forensic toxicology

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Main focus: relationship between xenobiotics and disease states
Diagnostic testing and therapeutic intervention
Consider specialty

Clinical toxicology

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The evaluation of environmental chemical pollutants and their impacts on human health

Environmental toxicology

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Describe environmental exposure to chemicals or drugs

biotics

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Describe substances from an animal, plant, mineral, or gas (venom,…)

poisons

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Endogenous substances biologically synthesized either in living cells or in microorganisms

toxins

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Highest mortality rate, poisoning cases

suicide

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Most frequently in kids. Also common in teens and adults with both therapeutic or illicit drugs

Accidental

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Correlates a single, acute oral dose range with the probability of a lethal outcome in

An average 70kg (154lb) male

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The predicted dose that would produce a toxic response in 50% of population

Toxic dose TD50

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Predicted dose that would result in death for 50% of population

Lethal dose LD50

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Predicted to have a therapeutic benefit or be effective in 50% population

Effective dose ED50

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Fewer toxic/adverse effects when dose is in the T.R.

larger therapeutic index

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Therapeutic index

Ratio of TD50 or LD50 to the ED50

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Toxicity that single, short-term exposure to a substance in which the dose is sufficient to cause immediate toxic effects

Acute

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Toxicity that associated with repeated and frequent exposure for extended time periods (months to years) at doses that are insufficient to cause an immediate acute response

Chronic

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Chronic may affect different systems than acute

True

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Toxic agents exhibit unique absorption, distribution, metabolism and elimination

Toxicokinetic

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“Trace element free” blood collection tubes

royal blue top

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tube for specifically for lead testing

tan blue top tube

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Most significant metabolism pathway for alcohols

Alcohol→(ADH)→Aldehyde→(ALDH)→Acid

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Exposure common for alcohol
Excessive consumption—leading cause of economic, social, and medical problems in the world

ethanol

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Legal limit for alcohols
Associated with decreased judgement and motor function

80 mg/dL

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What causes severe metabolic acidosis—can lead to tissue injury and possible death
Common lab solvent
Responsible for optic neuropathy that can lead to blindness

Methanol Formic acid

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Alcohol responsible for optic neuropathy that can lead to blindness

methanol

Rubbing alcohol Metabolized by hepatic ADH to acetone (end product)

isopropanol

Common component of hydraulic fluid and antifreeze Sweet taste Results in severe metabolic acidosis Rapid formation and deposition of calcium oxalate crystals in the renal tubules May result in renal tubular damage

ethylene glycol

How many time does affinity of Hgb to CO higher than O2

200-225 times

Half life of CO

60-90 min

Any exposure to strong acids or bases associated with injury Aspiration and ingestion—greatest hazards Aspiration associated with pulmonary edema and shock

caustic agents

Used in electroplating and galvanizing Pigments in paint and plastics Itai-itai disease Toxics to kidneys Half life 30 years

cadmium

Half life of lead in bones and soft tissue

20 years and 120 days

TUMOR MARKERS If cancer move to other parts of the body it is called

metastasis

Biomarker found in the blood or tissue and when elevated is linked to cancer

tumor marker

protein produced during fetal development and elevated in individuals with cancer

oncofetal antigens

Found on the surface of all nucleated cells Used as a non-specific marker of the high cell turnover common in tumors

beta macroglobulin

Valuable in diagnosing neuroblastomas, pituitary and adrenal adenomas

endocrine tumor marker

Monoclonal defined antigens identified from human tumor extracts and cell lines

Carbohydrate and Cancer Antigen Tumor Markers

“non-serological” markers Helps to choose between endocrine and cytotoxic therapies

receptor tumor markers

Tumor specific Absent in healthy individuals Readily detectable in body fluids

Ideal tumor marker

Study of the movement of drugs in the body

pharmacokinetic

the major transporter of drug

albumin

the phenomenon in which a drug is metabolized an results in a reduced concentration of the drug before reaching the circulatory system

1st pass effect

The study of the biochemical and physiological effects of drugs and their mechanisms of actions:

pharmacodynamics

This tumor marker often is measured in both the total and free form:

PSA

The concentration range of a drug within which the drug produces the desired effect:

therapeutic range

This tumor marker is primarily used as a marker for ovarian cancer: May be elevated in patients with endometriosis, 1st tri of pregnancy, or during menstruation

ca 125

This is found as a contaminant of homemade liquors and can cause optic neuropathy

methanol

This is a significant environmental pollutant and is easily taken up by crops – especially tobacco

cadmium

This is a cardioactive drug that is used to treat arrythmias and CHF. Biotin is known to interfere with this test:

digoxin

The most direct and effective route of administration of a drug

This is a common malignant tumor in kids associated with high levels of plasma, epinephrine, norepinephrine and dopamine

neuroblastoma

This test is used along with hCG to classify nonseminomatous tumor Often elevated in patients with hepatocellular carcinoma (HCC) and germ cell tumors

AFP

13) This is a kind of testing method that can be performed on solid tissue tumor markers

Immunohistochemistry

The predicted dose that would produce a toxic response in 50% of the population

TD50

This may occur when analyte concentrations exceed the analytical range excessively

hook effect

This drug is the hepatic metabolite of procainamide

NAPA`

This drug commonly is tested for both the total and free forms

phenytoin (dilantin)

Endogenous substances biologically synthesized either in living cells or in microorganisms

toxins

This method of analysis of toxic agent has good sensitivity but lacks specificity:

screening

These types of tumor markers are valuable in diagnosing neuroblastomas, pituitary and adrenal adenomas

endocrine tumor markers

This tumor marker is the prototypical oncofetal antigen and is used for monitoring colorectal cancer: Increased in heavy smokers and some patients following radiation treatments

CEA

Uses the results from animal experiments to predict what level of exposure will cause harm to humans:

Descriptive Toxicology

This is a metal with 3 forms, one of which is liquid at room temp

MERCURY

This is a useful system to compare relative toxicities of substances as the predicted endpoint is death:

Dose-Response Relationship

B-macroglobulin and immunoglobulins are part of this group of tumor markers:

Serum Protein Tumor Markers

Chemicals and drugs that are not normally found in or produced by the body:

Xenobiotics

This is an example of something that can have significant interference in immunoassays by cross-linking with the capture/label antibody:

HAMAs

This drug is ototoxic enough that it is recommended that baseline audiology testing is performed:

Tobramycin

Largely a result of the high metabolic demand of these proliferative cells Tend to correlate to tumor burden

enzyme tumor marker

Unique characteristics and concentrations of T.M.--2 major consideration

lack of standardization and wide range

Used to help diagnose carcinoid tumors, pheochromocytoma, & neuroblastoma

Catecholamines & metabolites

Rare tumor associated with hypertension Elevated plasma metanephrines, urine vanillylmandelic acid, free catecholamines

Pheochromocytoma

Elevated levels correlate with cancer stage of CA125

50% stage 1 90% stage 2 >90% stage 3 or 4

Dimeric hormone secreted by trophoblasts Elevated in trophoblastic tumors, mainly choriocarcinoma and germ cell tumors of ovary and testes Prognostic for ovarian cancer Diagnostic for classification of testicular cancer

HCG

produced in the epithelial cells of the acini and ducts of the prostate gland

glycoprotein

Mucin 1 (MUC1), Normally expressed in glandular or luminal epithelial cells Best application is serial testing for breast cancer patients

CA 15-3

Best validated biomarker for pancreatic cancer Modified Lewis (Le a ) blood group antigen

CA 19-9

Primarily used for ovarian cancer Improved specificity over CA-125—which can be elevated in non-malignant conditions like endometriosis

HE4

Auxiliary test for neuroendocrine tumors

NSE

drug absorption of weak acids

in stomach

drug absorption of weak bases

in intestine

the movement of a drug between blood circulation and tissues and organs and the relative proportion of the drug in the tissues

drug distribution

interact with site of action & result in biological response

free/unbound drugs

The biochemical pathway responsible for a large portion of drug metabolism

MFO - Hepatic mixed-function oxidase

number doses typically needed before steady-state oscillation is achieved

5-7

The science of studying variations and developing drug therapies to compensate for the genetic differences impacting therapy regimens

pharmacogenomic

Prominent gene affecting drug metabolism

CYP450

Natural product extracted from bark to treat arrythmias

quinidine

Treat gram neg and some gram pos infections Inhibit bacterial protein synthesis

aminoglycosides

Treats GNR—life threatening

gentamicin

Treat severe blood infections Can be administered orally to reduce intestinal flora

amikacin

“redman syndrome”—extremity flushing Against GPC and GPR Poor GI absorption

vancomycin

Used to treat and suppress seizures Only effective while drug metabolites are in the body goal: get therapeutic benefit with little to no adverse effects

Antiepileptic Drugs (AEDs)

Grand mal seizures—when resistance to other AEDs

primidone

Severe adverse events—only use if no response to other AEDs

carbamazepine

Mood altering used to treat: Bipolar disorder, recurrent depression, aggressive or self-mutilating behavior Also preventative for cluster headaches or migraines

lithium

Used to treat depression, insomnia, extreme apathy, loss of libido Ex: imipramine, amitriptyline, doxepin

TCA

Used to treat refractory schizophrenia Absorption rapid and complete

clozapine

Treats schizophrenia, acute manic episodes, recurrence of bipolar disorders Can be IM but usually oral

olanzapine

Cyclic polypeptide--suppress graft vs host rejection of heterotopic transplanted organs

cyclosporine

Antifungal agent used to prevent graft rejection in kidney transplants

sirolimus

Derived form sirolimus Short half life—more rapid achievement of steady state pharmacokinetics

everolimus

prodrug that is rapidly converted in the liver to its active form, MPA (Mycophenolic Acid)

Mycophenolate mofetil

Assessment of therapeutic benefit not aided by TDM because pharmacodynamics are hard to establish EX drug: methotrexate

Antineoplastics

Used to treat respiratory disorders For patients who can’t use an inhaler or have nocturnal symptoms

theophylline

Describes the changes in health effects of a defined population based on the exposure to the xenobiotic

quantal dose-relationship

Toxic agents exhibit unique absorption, distribution, metabolism and elimination

toxicokinetics

Methods used for analysis of toxic agents

Immunoassays-common for most drug screens Gas chromatography (GC) with mass spectrometry (MS) Reference method for most organic compounds Liquid chromatograph with tandem mass spectrometer (LC-MS) Emerged as an important analytical technique Inorganic compounds Use inductively coupled plasma mass spec (ICP-MS) or atomic absorption (AA) methods Nuclear magnetic resonance (NMR) spectroscopy has potential applications

Most significant metabolism pathway of alcohol

Alcohol→(ADH)→Aldehyde→(ALDH)→Acid

reactive intermediate, most converted to acetate but some is released in the free state

Acetaldehyde

osmolality ratio of osmo to serum ethanol

Serum osmo increases 10 mOsm/kg per 60 mg/dL increase in serum ethanol

Super-toxic substance Used in industrial processes, insecticides, rodenticides Binds to heme iron High lactic levels commonly found

cyanide

Less harmful organic forms with foods Clams, oysters, scallops, mussels, crustaceans, bottom feeding fish

arsenic

Potent inhibitor of many enzymes Noteworthy effects on Vit D metabolism and heme synthesis

lead

Intentionally added to environment to harm or kill something Insecticides, herbicides, fungicides, rodenticides Found in occupational and home settings

pesticides

Reye’s syndrome with viral infections in kids

salicylates common drug: Acetylsalicylic acid—aspirin

Overdose associated with severe hepatotoxicity Alcoholics more susceptible

Tylenol

Confirmation testing for drug abuse

immunoassays -more common

Typical screening panel

Amphetamines, barbiturates, benzodiazepenes, cocaine, opioids, THC, tricyclic antidepressants

Originally sleep inducers Most commonly abused Used as “downer” after cocaine or amphetamine “high”

barbiturate

Depressants of CNS Among drugs most commonly prescribed because of: Efficacy, safety, low addiction potential, minimal side effects, high public demand for sedative and anti-anxiety

Benzodiazepines Diazepam (Valium), chlordiazepovide (Librium), lorazepam (Ativan) alprazolam (Xanax)

Psychoactive compounds found in marijuana

Cannabinoids: Tetrahydrocannabinol (THC)

Effective local anesthetic, few adverse effects at therapeutic concentrations Alkaloid salt

cocaine

Used to treat depression and mood disorders Imipramine metabolizes to desipramine Amitriptyline metabolizes to nortriptyline Doxepin metabolizes to nordoxepin

Tricyclic Antidepressants (TCAs)

Amphetamine derivative “ecstasy”

Methylenedioxymethamphetamine (MDMA)

“angel dust” Illicit drug with stimulant, depressant, anesthetic, and hallucinogenic properties

Phencyclidine (PCP)

Used to increase muscle mass to improve athletic performance Can cause enlargement of the heart

Anabolic Steroids

A drug's most direct and effective method of delivery to its site of action is:

Intravenous administration

Which of the following is not true regarding the absorption of drugs? Drug absorption rates may change with age Morphine may slow the gastrointestinal motility of a drug Liquid medications are often absorbed slower than capsule medications Crohn's disease may alter the absorption of some drugs

Liquid medications are often absorbed slower than capsule medications

T/F Drugs are susceptible to hepatic metabolism, and this increases the concentration of the drug before it reaches the circulatory system.

false

Which of the following statements is true regarding drug elimination? One drug half-life is the time needed for the drug concentration to increase by half Five to seven drug doses are required to reach a steady state of drug concentration Most medications are administered as a single dose versus a scheduled basis Aminoglycoside antibiotics are reabsorbed by the renal tubules

Five to seven drug doses are required to reach a steady state of drug concentration

The relationship between a drug's concentration at its target sites and its physiological responses is known as:

Pharmacodynamics

Which of the following is not true concerning therapeutic drug monitoring? It ensures correct drug doses for the expected therapeutic range It helps to identify non-compliance of the patient It identifies drug-drug interactions if multiple drugs are taken simultaneously It establishes a one-fit dosing model for all patients

It establishes a one-fit dosing model for all patients

A blood draw to determine a peak level of a drug should be drawn:

One hour after an orally administered dose

CYP450 is a gene that influences the effectiveness of a drug in an individual. T/F

True

Which of the following is not true concerning aminoglycosides?

Ototoxic effects of the drug are reversible

Pharmacokinetics and drug concentration are influenced by which of the following factors?

Absorption, distribution, metabolism, excretion

Only bound fractions of drugs can interact with the site of action and result in a biological response.

False

Tolerance to drugs could be explained as:

Constant exposure of receptors to drugs that leads to a reduced response

This drug is used to treat arrhythmias and CHF.

Digoxin

This drug may have the adverse effect of "redman syndrome"

Vancomycin

This antiepileptic drug requires hepatic markers to be check frequently due to risk of hepatic dysfunction.

Valproic acid

Immunosuppressive drugs typically are collected as serum samples. true/false

false

Common routes of exposure to toxins are through the gastrointestinal tract, lungs, and skin. t/f

true

Which specimen type is preferred for analytes demonstrating variation in urinary elimination patterns?

24-hour collection

Which of the following is not true concerning analysis of toxic agents?

Screening tests have good specificity but lack sensitivity

All of the following statements are true regarding blood alcohol measurements except: During venipuncture, the skin must be disinfected with iodine or chlorohexidine gluconate Plasma and serum are acceptable specimen types for analysis When testing will be delayed, sodium chloride can be used as a preservative to maintain specimen integrity Specimens should remain capped to avoid evaporation

When testing will be delayed, sodium chloride can be used as a preservative to maintain specimen integrity

The affinity of carbon monoxide for hemoglobin is 20-25 times greater than oxygen t/f

false

Toxic levels of acetaminophen are associated with

Hepatotoxicity

Which of the following statements is not true concerning testing for drugs of abuse?

Confirmatory testing must use methods with high specificity and low sensitivity

Which type of toxicology uses the results from animal experiments to predict what level of exposure will cause harm to humans?

Descriptive

Which is not a common route of exposure to toxic substances. Ingestion Intravenous Inhalation Transdermal absorption

What phrase best describes what ED50 stands for?

A drug is predicted to have a therapeutic benefit for 50% of the population.

Chronic exposure to a toxin always has the same effect as acute exposures. t/f

false

Which is not a common specimen type for analysis of toxic agents? urine blood oral fluid

all are common

An alternative test that may be performed in order to estimate ethanol in serum is the osmolality. t/f

true

This toxic substance can be found in its organic form in clams and oysters.

arsenic

This environmental pollutant has been linked to Itai-itai disease.

cadmium

Which of the following enzymes is increased in patients with cancer involving bone?

Alkaline phosphatase

Which tumor marker is associated with neuroblastoma?

HVA

The utilization of tumor markers is most important for:

Monitoring the effectiveness of treatment

Abnormally low tumor marker concentrations are associated with antigen deficiency and can cause false negative results t/f

false

To accurately monitor tumor marker levels of the patient, it is important to use the same methodology each time of testing. t/f

true

If tumor cells are found in both the original tumor and also in the regional lymph nodes, this would be classified as stage:

All tumor markers can be used to screen asymptomatic populations. t/f

false

Which is not something that is a consideration when considering using immunoassay method for tumor markers. Hook effect Requires more specialized skill and experience Assay linearity HAMAs

Requires more specialized skill and experience

Serotonin secreting tumors from small intestine

carcinoid

Which is not an example of an enzyme tumor marker. ALP AST PSA LDH

AST

Which tumor marker is used primarily with hepatocelluar carcinoma and testicular cancer. AFP CA-125 CEA hCG

AFP

Elevations in this tumor marker in CSF may indicate Creutzfeldt-Jakob disease.

NSE

A patient has a synovial fluid removed from their knee joint. The test results included a cell count with differential. The WBC count was 65,000 with 93% neutrophils. What is the most likely cause?

septic

A patient has CSF chemistries and microbiology samples performed. Chemistries yield a very low glucose value but no growth is reported in micro cultures. What is a possible pathology to explain these results? It is to be noted that the CSF had a clear, colorless appearance.

brain tumor

Which is not a common test to perform on a CSF sample? glucose uric acid protein lactate

uric acid

Increased CSF glucose levels can indicate acute bacterial meningitis. T/F

false

Which would typically not be a cause of an exudative pleural effusion? Pulmonary abscess Lymphoma Bacterial pneumonia Hepatic cirrhosis

Hepatic cirrhosis

The unique structure of hemoglobin allows it to act as both an acid-base buffer and O2 buffer. T/F

true

Breakdown of glycogen to glucose for use as energy

Glycogenolysis

Conversion of glucose to glycogen for storage

Glycogenesis

Formation of glucose of-6-phosphate from noncarbohydrate sources

Gluconeogenesis

Metabolism of glucose molecule to pyruvate or lactate for production of energy

Glycolysis

Which parameter on a blood gas analysis is calculated instead of being directly measured.

HCO3

The best collection tube to use for glucose tolerance testing is: Gold top/serum Grey top/NaF Green top/lithium heparin Lavender top/EDTA Grey top/NaF

Grey top/NaF

What is the incremental fraction of oxygen at sea level?

21%

In external respiration, the partial pressure of oxygen in the alveolar membrane is __________, while the partial pressure of oxygen in the venous blood is _________.

100 mmHg, 40 mmHg

A decrease in H+ ions, an increase in pH, and a decrease in pCO2 results in what acid-base disorder?

Respiratory alkalosis

A patient with an HA1C of 12% would be most likely to have an estimated average glucose of:

298 mg/dL

A patient with a fasting glucose of 122 mg/dL would be considered to have a:

Impaired fasting glucose

This type of diabetes is noted to have insulin resistance with an insulin secretory defect due to progressive loss of adequate beta cell insulin secretion.

Type 2

As a CSF is collected, it is placed in a series of tubes for analysis. The correct order of testing should be:

Chemistry, Microbiology, Hematology

An increase in H+ ions, a decrease in pH, and an increase in pCO2 results in what acid-base disorder?

Respiratory acidosis

Which is not stimulated by epinephrine? Insulin Glucagon Glycogenolysis Gluconeogenesis

insulin

Match the type of pancreatic cell with what it produces. Cell: Alpha cell, beta cell, delta cell Product: glucagon, insulin, somatostatin

alpha - glucagon beta - insulin delta - somatostatin

Diabetic condition formed when a person's own immune system destroys the islet cells of the pancreas, resulting in impaired production of insulin.

type 1

It is recommended that all adults have a lipid profile performed every _____.

5 years

Women, on average, have higher HDL levels and lower total cholesterol and triglyceride levels than men. T/F

True

HDL has a major role in this type of lipid pathway

Reverse cholesterol pathway

Which is the type of lipoprotein that contains the apolipoprotein Apo B48?

Chylomicrons

Amphipathic lipid molecules contain both hydrophobic fatty acid chains and hydrophobic head groups. T/F

False

Calculate the LDL from the following test results. Total cholesterol: 223 mg/dL HDL: 65 mg/dL Triglycerides: 290 mg/dL

100

The function of the major lipid components of the very-low density lipoproteins is to transport:

Endogenous triglycerides

Turbidity in serum suggests elevation of:

Chylomicrons

Electrolytes that reabsorbed under influence of PTH

calcium

electrolytes that recovered from glomerular filtrate

bicarbonate

electrolytes that reabsorbed by passive transport in proximal tubule

chloride

Reabsorption occurs in Henle's loop

Magnesium

A rare disease of water and salt imbalance.

Diabetes insipidus

Of the total serum osmolality; sodium, chloride, and bicarb normally contribute what percent?

What is the type of lipoprotein that is known to contribute to plaque formation.

LDL

A patient presents to the ER with flushed skin, severe agitation, low-grade fever, and complaints of being extremely thirsty. Given these symptoms, what pathology would you consider?

Hypernatremia

Which of the following is not associated with an increase in anion gap when it occurs in a single patient? Renal failure Ketoacidosis Glycol poisoning Instrument error

Instrument error

Causes of increased levels of protein in CSF include all but: Decreased dialysis of proteins from the plasma Lysis of contaminant blood from traumatic tap Increased permeability of the epithelial membrane Obstruction

Decreased dialysis of proteins from the plasma

In order to maintain electrical neutrality in the red blood cell, bicarbonate leaves the red blood cell and enters the plasma through an exchange mechanism with what electrolyte?

Chloride

Of total serum calcium, free ionized calcium normally represents approximately what percent?

The presence of only slightly visible hemolysis will significantly increase the serum level of which of the following analytes?

Potassium

What is the major intracellular cation?

potassium

What is the major extracellular cation?

Sodium

Unsaturated triglycerides are typically solid at room temperature. T/F

false

The cation is the fourth most abundant cation in the body and second most abundant intracellularly. Hint: Consumption of processed foods can lead to inadequate intake and subsequent deficiency.

Magnesium

Water makes up what percentage of body weight?

40-75%

Which phrase does not describe phospholipids. Hydrophobic head group Synthesized in all organs Amphipathic Unsaturated steroid alcohol

Unsaturated steroid alcohol

Electrolyte essential for myocardial contraction and important to maintain normal levels for critically ill patients.

calcium

Type of CK isoenzyme with its specificity CK: cardiac, muscle, brain Specificity: CK-MB, CK-BB, CK-MM

Cardiac=CK-MB Muscle=CK-MM Brain=CK-BB

Amylase is more specific to pancreatitis than lipase. T/F

false

This test has greater specificity to liver damage.

ALT

In many reactions, we are looking at the reaction of the cofactor NADH to NAD to determine the value of the enzyme. T/F

true

This enzyme has a short half-life and is found in the heart, liver, skeletal muscle, and kidney.

AST

The hook effect refers to high concentrations of analyte producing a lower signal than expected. T/F

true

These type of inhibitor associate with enzymes at places other than the active site.

non-competitive

These type of inhibitor share structural features found in the substrate.

competitive

These type of inhibitor bind only to the ES complex.

uncompetitive

In this state, not all enzyme sites are saturated with substrate and substrate concentration is the rate-limiting step.

1st order

An inactive, secreted form of the enzyme

zymogen

The following statement could be used to describe zero-order kinetics: T/F Substrate is present in excess, rate of reaction is constant with time and dependent only on the concentration of enzyme in the system.

true

When measuring enzyme activity, if the instrument is operating at 50 C lower than the temperature prescribed for the method, how would the results be affected?

Lower than expected

What does an increase in serum enzyme levels indicate?

Tissue damage and necrosis

Pathological condition in which the proximal tubules in the kidneys do not reabsorb glucose, amino acids, uric acids, and bicarbonates resulting in their loss to the urine concentrate.

Fanconi Syndrome

This test can be used to monitor alcoholics with liver toxicity

GGT

Which of the following serves as the glomerular filtration rate for clinicians?

creatinine

Plasma creatinine levels are determined by all of the following except: Relative muscle mass Rate of creatine turnover Renal function Dietary intake of protein

Dietary intake of protein

A 56 year old male with gout is given allopurinol then returns to the ER a week later with a uric acid level of 8.6 mg/dL (2.4-7.0 mg/dL). What statement best describes the reason for the uric acid level? The patient did not take prescribed medication The patient overdosed on allopurinol Allopurinol returned uric acid levels to normal

The patient did not take prescribed medication

What is an energy source utilized by muscles?

Creatine phosphate

This non-protein nitrogen compound is found in the highest concentration in the blood.

Urea nitrogen

Which is not a clinical application of measurement of urea. Assess hydration status Evaluate liver function Verify adequacy of dialysis Determine nitrogen balance

Evaluate liver function

Match the BUN:Creatinine ratio with the correct location of azotemia. 23 11 8 postrenal intrarenal prerenal

23 - pre 11 - post 8 - intrarenal

Which is not a likely cause of decreased BUN. High protein dietary intake Liver disease Severe vomiting Increased protein synthesis

high protein dietary intake

The most frequently used analytic method for creatinine testing is the:

Jaffe reaction

Which test has the most strict collection requirements that include transporting the specimen on ice and testing immediately.

Ammonia

disease associate with severe protein deficiency

Kwashiokor

disease associate with severe protein and calorie deficiency

Marasmus

Which is a negative acute phase reactant?

Transferrin

This protein is known for being a nephrotoxin.

Myoglobin

This test may be used to assess nutritional status.

Prealbumin

Proteins with 10-40% carbohydrates attached are

Glycoproteins

Proteins consist of the elements: Carbon Oxygen Nitrogen All of these None of these

all

In the stomach ______ breaks down proteins into peptides.

pepsin

When a protein is disturbed and loses its functional and chemical characteristics, it is called:

Denaturation

Essential amino acids: Must be obtained through diet Are synthesized by the body

Must be obtained through diet

In cerebral spinal fluid, ______% of protein comes from plasma, while ______% comes from the brain.

95%, 5%

When proteins have a more positive charge they are more easily dissolved. T/F

True

Which is not true of amino acid analysis? Collect sample in a heparin tube Blood samples should be drawn after a 2-3 hour fast Analysis should be performed immediately or sample frozen Plasma should be removed carefully to avoid platelets and white blood cells

Blood samples should be drawn after a 2-3 hour fast

This type of analytical method measures the amount of light that can pass through a sample at a 180O angle from the incident light.

Turbidimetry

Stray light refers to any wavelengths outside the band transmitted by the monochromator. T/F

true

Dynodes are a series of anodes with successively higher voltages. T/F

true

An advantage of a photocell over a phototube is that a photocell has an external power source and is more sensitive with lower amounts of light. T/F

false

Calculate % transmittance through a tube containing 5 layers of solution with an absorbance of 20%.

33%

This type of lamp is used in visible and infrared regions and is the most common type:

tungsten

Visible light falls between the color ______ at 400 nm and _____ at 700 nm.

violet, red

Which is the order that you would expect to see in LD isoenzymes in a patient who has had a heart attack.

LD1>LD2>LD3>LD4>LD5

Chemistry Exam 3 Flashcards

(269 cards)