1. Chemistry - Special Chemistry
100. Aminoglycosides can cause severe toxicity including which of the following? A. Nephrotoxicity and ototoxicity B. Hepatitis C. Edema D. Red man syndrome
A
5. All of the following hormones are produced primarily in the pancreatic islets EXCEPT which one? A. Gastrin B. Glucagon C. Insulin D. Pancreatic polypeptide
A gastrin
19. The principal amount of testosterone in males is produced by which endocrine gland? A. Adrenals B. Testes C. Pituitary D. Hypothalamus
B
20. Which of the following action describes the MAJOR property of antidiuretic hormone? A. Acts on proximal tubules. B. Changes distal tubule water permeability C. Acts on Na/K/(H') pump D. Cannot be affected by diuretics
B
27. An elevated level of which of the following hormones will inhibit pituitary secretion of adrenocorticotropic hormone (ACTH)? A. Aldosterone B. Cortisol C. Testosterone D. Progesterone
B
32. A patient with truncal obesity, hypertension, a ruddy/striated complexion and mood swings has multiple elevated glucose values. A fasting ACTH sample is also elevated. The physician orders a dexamethasone test, which shows an elevated cortisol level (no suppression). What is the most likely cause of the patient's values and symptoms? A. Addison's Disease B. Cushing Syndrome C. Cushing Disease D. Diabetes
B
34. A major action of angiotensin 2 is: A. Increased pituitary secretion of petressin B. Increased vasoconstriction C. Increased parathormone secretion by the parathyroid D. Decreased adrenal secretion of aldosterone
B
35. ACTH controls which step of steroid hormone production? A. First step (cholesterol to cholesterol esters) B. First step (cholesterol esters to cholesterol) C. Second step (cholesterol to pregnenolone) D. Third step (cholesterol esters to pregnenolone)
B
36. The production of neutral 17-ketosteroids is a measure of which of the following? A. Cholesterol production B. Androgen production C. Estrogen production D. Growth hormone
B
41. Which enzyme is responsible for the rate-limiting step of steroid hormone synthesis? A. 21-hydroxylase B. CYP450 C. F-zone enzymes D. 17-hydroxylase
B
42. In patients with suspected primary hypothyroidism associated with Hashimoto's thyroiditis, one would expect the following laboratory test results:T4 ___? TSH ___? TRH stimulation ___? A. Increased, decreased, increased B. Decreased, increased, increased C. Increased, decreased, decreased D. Increased, increased, decreased
B
43. A patient has the following test results: Increased serum phosphorus level, decreased serum calcium level, and decreased serum parathyroid hormone (PTH) level. This patient MOST likely has: A. Hyperparathyroidism B. Hypoparathyroidism C. Hypercalcemia D. Hypokalemia
B
45. A critically ill 86-year-old female was admitted to the intensive care unit (ICU) after arriving at the emergency department with symptoms that included shortness of breath and fever. Her temperature was 39°C (102°F) and pulse rate 110/minute. A white blood count (WBC) was ordered and was elevated at 15.0 x 109/L. The differential showed an increase in segmented and immature neutrophils. Other testing was ordered after admission to ICU, including a procalcitonin (PCT). The result was 2.15 ng/mL (Reference value for normal at the 95th percentile is <0.05 ng/mL). Given the clinical assessment and laboratory test results, what may the increased procalcitonin indicate? A. Low risk of severe sepsis/septic shock B. High risk of severe sepsis/septic shock C. Systemic inflammation, not related to infection D. No risk of severe sepsis/septic shock
B
25. A 64-year old man lost 15 pounds, became weaker, and his face became fuller with a ruddy complexion. His laboratory tests revealed: Serum cortisol 8 AM: 880 nmol/L, 138-635 nmol/L (reference range) 4 PM: 828 nmol/L, 83-414 nmol/L (reference range) After these results, an overnight dexamethasone suppression test gave a cortisol level of 773 nmol/L. The MOST probable diagnosis for this patient is: A. Congenital adrenal hyperplasia B. Addison's disease C. Cushing's Syndrome D. Conn's Syndrome
C
21. Follicle stimulating hormone (FSH) is produced by: A. Adrenal cortex B. Adrenal medulla C. Pituitary D. Thyroid
C
7. All of the following are characteristics of type 2 diabetes mellitus EXCEPT: A. Insulin levels may or may NOT be abnormal. B. More common than type 1 diabetes. C. Requires insulin therapy to control hyperglycemia. D. It commonly occurs in adults
C. Requires insulin therapy to control hyperglycemia
22. All of the following statements about fluorometry are true, EXCEPT: A. Fluorometry is more sensitive than spectrophotometry. B. Both excitation and emission spectra are characteristics of the analyte. C. Fluorescence is indirectly proportional to the analyte being measured. D. Fluorometers typically utilize monochromators or optical filters
C
24.An adult's plasma cortisol of 22 µg/dL at 8:00 a.m. and 10 µg/dL at 4:00 p.m. would be: A. Consistent with Addison's disease B. Consistent with Cushing's syndrome C. Found in a healthy individual D. Consistent with pheochromocytoma
C
79. Which of the following choices is correct when describing the principles of competitive radioimmunoassay procedures? A. Antibody will react preferentially with the labeled antigen B. Antibody will react preferentially with the unlabeled antigen C. Antibody will react with labeled antigen only D. Antibody will react equally with labeled and unlabeled antigen
D
81. When a patient is suspected of intoxication, what would you expect the osmol gap to be? A. Slightly decreased B. Normal C. Extremely decreased D. Increased
D
85. Which of the following is a true statement about aminoglycoside antibiotics? A. Aminoglycosides have a half-life of 1-2 hours and are metabolized by the liver. B. Aminoglycosides are anitbiotics used to treat only Gram-negative bacterial infections. C. Aminoglycosides are antibiotics used to treat only Gram-positive bacterial infections. D. Aminoglycosides can be toxic antibiotics that are used to treat bacterial infections when such bacteria are resistant to less-toxic antibiotics.
D
90. Ninety-nine percent of lead absorbed in the body is taken up by what after absorption? A. Lungs B. Gastrointestinal tract C. Heart D. Erythrocytes
D
1. Pheochromocytoma is a tumor of the adrenal medulla that results in elevated urinary levels of all the following EXCEPT: A. Cortisol B. Free catecholamines C. Metanephrines D. Vanillylmandelic acid
A cortisol
73. Which of the following drugs is used to treat asthma and COPD in patients with nocturnal symptoms or problems with inhalers? A. Theophylline B. Methotrexate C. Tacrolimus D. Mycophenolic acid
A
14. Which of the following statements regarding the L/S ratio is TRUE? A. A ratio of 2:1 or greater usually indicates adequate pulmonary surfactant to prevent respiratory distress syndrome (RDS) B. A ratio of 1.5:1 indicates fetal lung maturity in pregnancies associated with diabetes mellitus. C. Sphingomyelin levels increase during the 3rd trimester causing the L/S ratio to fall slightly during the last two weeks of gestation. D. A phosphatidylglycerol (PG) spot indicates the presence of meconium in the amniotic fluid
A
15. A patient is suspected of having Cushing's syndrome. His doctor is ordering a cortisol level. Which of the following are true about the diurnal variation of cortisol levels in blood? A. Cortisol levels are higher in the morning B. Cortisol levels are higher in the evening C. Cortisol levels are lower in the morning D. There is no diurnal variation of cortisol in blood
A
16. All of the following hormones increase or decrease plasma glucose concentration by regulating glycogenolysis (converting glycogen to glucose) EXCEPT? A. Cortisol B. Glucagon C. Epinephrine D. Insulin
A
23. Estrogen (ERs) and progesterone (PRs) receptors used as tumor markers are most commonly employed to provide prognostic information about: A. Breast cancer B. Uterine cancer C. Menopause D. Cervical cancer
A
29. What is the effect of aging with the hormones of the endocrine system? A. Aldosterone decreases and norepinephrine increases B. Aldosterone increases and norepinephrine increases C. Aldosterone decreases and norepinephrine decreases D. Aldosterone increases and norepinephrine decreases
A
30. Serum calcitonin is typically elevated in which of the following conditions? A. Medullary carcinoma of the thyroid B. Hyperthyroidism C. Glioblastoma D. Adrenal adenoma
A
31. Which of the following describes gastrin's role in digestion? A. Stimulates gastric acid-HCl secretion B. Stimulates secretion of a base to lower the stomach's pH C. Is secreted when the gastric fluid pH is low to buffer fluid D. Inhibits the secretion of intrinsic factor
A
38. Which one of the following adipocyte products is an important messenger in metabolism, signaling the hypothalamus that there are changes in fat stores? A. Leptin B. Resistin C. IL-6 D. Angiotensinogen
A
39. Which one of the following statements about thyroid-stimulating hormone (TSH) is true? A. It is decreased in hyperthyroidism B. It is decreased in hypothyroidism C. A sensitive TSH assay is not a good screening test for thyroid function D. Diffuse toxic goiter is associated with elevated TSH levels.
A
49. Serum TSH levels five-times the upper limit of normal in the presence of a low T4 and low T3 uptake could mean which of the following: A. The thyroid has been established as the cause of hypothyroidism B. The thyroid is ruled-out as the cause of hypothyroidism C. The pituitary has been established as the cause of hypothyroidism D. The diagnosis is consistent with secondary hyperthyroidism
A
50. All of the following hormones stimulate gluconeogenesis, the formation of glucose from noncarbohydrate sources such as amino acids, glycerol, and fatty acids, EXCEPT? A. Insulin B. Thyroxine (T4) C. Cortisol D. Glucagon
A
53. Which of the following is necessary for the absorption of Vitamin B12: A. Intrinsic factor B. Folic acid C. Gastrin D. Insulin
A
56. A deficiency in which of the folowing vitamins is associated with "Beriberi"? A. Thiamine B. Vitamin C C. Vitamin A D. Vitamin D
A
71. The amount of time it takes for a drug's concentration in the body to decrease by 50% is referred to as? A. Drug half-life B. Therapeutic window C. Pharmacokinetics D. Pharmacogenomics (Pharmacogenetics)
A
75. Which of the following statements regarding peak level in therapeutic drug monitoring is true? A. Peak level is assessed by collecting a blood sample after a dose of the drug is given (at a specified time). B. Peak level is assessed by collecting a blood sample right before the next dose of the drug is given. C. Peak level is the point at which the drug is lowest in the patient's body. D. Peak level is assessed by collecting a urine sample right after the next dose of the drug is given.
A
83. Which of the following immunosuppressive drugs below has been associated with thrombus formation in patients with toxic levels? A. Tacrolimus B. Cyclosporine C. Sirolimus D. Mycophenolic acid
A
84. Which medication would be prescribed for narcolepsy? A. Amphetamine B. Digoxin C. Dilantin D. Phenobarbital
A
89. When testing for ethanol, what is actually measured in the enzymatic reaction, that is proportional to ethanol concentration? A. NADH B. Acetaldehyde C. Acetone D. NAD
A
91. Which one of the following statements about acetaminophen metabolism is false? A. It is metabolized in the kidney B. It is largely metabolized in the liver to glucuronide and sulfonate conjugates C. A small amount is metabolized via cytochrome oxidase to a reactive benzoquinoneimine intermediate D. The benzoquinoneimine intermediate becomes toxic to the liver once tissue glutathione becomes depleted
A
93. How does Aspirin (salicylic acid) affect platelet function? A. Inhibiting cyclooxygenase B. Activates lipids C. Inhibiting carbohydrates D. Activating nucleic acid
A
10. Which of the following is considered an action of the hormone glucagon? A. Increase glycogenolysis B. Increase glycogenesis C. Increase glycolysis D. Increase lipogenesis
A Increase glycogenolysis
9. Hormonal variation throughout the menstrual cycle typically shows: A. An abrupt rise in luteinizing hormone (LH) 3-36 hours prior to ovulation B. Progesterone peaking at ovulation then falling C. Estrogen peaking at ovulation then falling D. An abrupt decrease of LH 3-36 hours prior to ovulation
A. An abrupt rise in luteinizing hormone (LH) 3-36 hours prior to ovulation
6. Estriol levels in conjunction with hCG, inhibin A (inhA), and alpha-fetoprotein (AFP) can be obtained during pregnancy to: A. Assess the risk of Down's syndrome B. Assess fetomaternal function C. Assess for multiple gestations D. Assess for maternal diabetes mellitus
A. Assess the risk of Down's syndrome
46. The ultimate end product of both epinephrine and norepinephrine metabolism is: A. Metanephrine B. Vanillylmandellic acid (VMA) C. Homovanillic acid (HVA) D. Cortisol
B
54. Vitamin D is formed in the skin and hydroxylated in two places before it is in its active form of 1,25-dyhydroxy vitamin D. Where does the second hydroxylation occur? A. Liver B. Kidneys C. Skin D. Intestines
B
58. A deficiency in which of the folowing vitamins is associated with "Scurvy"? A. Thiamine B. Vitamin C C. Vitamin A D. Vitamin D
B
59. Albumin levels are can be a good gauge for chronic protein deficiency. Which of the following terms describes inadequate protein and caloric intake? A. Kwashiorkor B. Marasmus C. Albuminemia D. Hypoproteinism
B
62. Which of the following is considered the major transport protein for vitamin A? A. Transthyretin B. Retinol-binding protein C. Transferrin D. Haptoglobin
B
63. The most common testing method for vitamin E determination is by: A. Protein binding radioimmunoassay (RIA) B. High-performance liquid chromatography (HPLC) C. 2,4-dinitrophenylhydrazine D. Not assayed - prothrombin time is used as a functional indicator of vitamin D status.
B
65. What are the 3 main effects of active vitamin D on the body? A. To absorb calcium in the intestines, from bone, and in the kidneys B. To absorb calcium and phosphorus in the intestines, from bone, and in the kidneys C. To excrete calcium and phosphorus in the GI tract, by the kidneys, and by the mineralization of bone. D. To excrete calcium in the GI tract, by the kidneys, and by the mineralization of bone.
B
66. Which one of the following statements concerning Vitamin D is correct? A. Vitamin D deficiency is a cause of scurvy. B. Vitamin D acts as a hormone in calcium regulation. C. Vitamin D functions in part to aid in optic nerve transmission. D. One form of Vitamin D is referred to as pyridoxal phosphate.
B
69. What is the half-life for aminoglycoside antibiotics in the blood? A. 1-2 hours B. 2-3 hours C. 3-4 hours D. 4-5 hours
B
78. A drug that is administered through which of the following routes will reach peak level the quickest? A. Oral B. Intravenous (IV) C. Intramuscular (IM) D. Subcutaneous (SC)
B
80. Which of the following is a component of antifreeze that can cause severe renal tubular damage, along with similar effects of alcohol poisoning? A. Ethanol B. Ethylene glycol C. Isopropanol D. Methanol
B
92. You are collecting a blood specimen to be used for forensic (legal) alcohol testing. Which of the following must be done before you can start the specimen collection process? A. Label the tubes in the presence of the patient. B. Must inform the patient that the blood about to be collected is for alcohol testing. C. Seal the collection tubes in front of the patient. D. Collect the specimen, the patient does not need to be informed what the blood is collected for.
B
94. A mother and young child arrive at the outpatient laboratory with a physician's order for a lead test on the child. The phlebotomist decides to perform a dermal puncture (fingerstick). What procedure is important to implement when a test for lead is collected by finger puncture that would NOT be necessary prior to an antecubital venipuncture? A. Asking the patient or child's parent to state his/her name and date of birth. B. Thoroughly washing patient's hands with soap and water. C. Cleansing the puncture site with alcohol and letting the alcohol air dry. D. Labeling the specimen with at least two patient identifiers.
B
95. Which term describes the dose of the drug in which 50% of the individuals will result in mortality? A. ED50 B. LD50 C. TD50 D. MD50
B
96. Enzyme-multiplied immunoassay techniques (EMIT) differ from all other types of enzyme immunoassays in that: A. Lysozyme is the only enzyme used to label the hapten molecule B. No separation of bound and free antigen is required C. Inhibition of the enzyme label is accomplished with polyethylene glycol D. Antibody absorption to polystyrene tubes precludes competition to labeled and free antigen
B
97. Which of the following is an example of a specimen which requires a chain-of-custody procedure to be followed? A. A throat swab collected in a outpatient clinic. B. A urine drug screen for pre-employment C. A sputum culture on a emergency room patient suspected of pneumonia D. A urine culture on a pediatric patient with a urinary tract infection (UTI)
B
4. The parathyroid hormone (PTH) is important in the regulation of: A. Iodine and bromine B. Calcium and phosphate C. Acid and alkaline phosphatase D. Zinc and magnesium
B. Calcium and phosphate
8. Enzyme-multiplied immunoassay techniques (EMIT) differ from all other types of enzyme immunoassays in that: A. Lysozyme is the only enzyme used to label the hapten molecule B. No separation of bound and free antigen is required C. Inhibition of the enzyme label is accomplished with polyethylene glycol D. Antibody absorption to polystyrene tubes precludes competition to labeled and free antigen
B. No separation of bound and free antigen is required
26. What is the purpose of the BNP test? A. Determines the amount of urea in blood. B. Evaluates abnormalities in the extrinsic coagulation pathway and monitors coumarin therapy. C. Rules out acute heart failure in the emergency setting. D. Evaluates abnormalities in the intrinsic coagulation pathway and monitors heparin therapy.
C
33. From the groups of analytes below, which set would most likely be INCREASED in a type 1 diabetic patient in crisis? A. Insulin and blood glucose B. Insulin and ketone bodies C. Ketone bodies and blood glucose D. Ketone bodies and blood pH
C
37. Human chorionic gonadatropin (hCG) is used in the determination of: A. Liver function B. Fetal maturity C. Pregnancy D. Steroid levels
C
44. The following BEST describes serum hCG levels during pregnancy: A. Rise in levels throughout pregnancy B. Highest levels found at end of pregnancy C. Rapid rise in levels during first trimester; slow decline and possible level-off throughout remainder of pregnancy D. Slow rise in levels during first trimester; rapid rise during second trimester; slow decline during the third trimester
C
47. Which marker is most useful for detection of gestational trophoblastic disease? A. CEA (Carcinoembryonic antigen) B. AFP (a-fetoprotein) C. hCG (human chorionic gonadotropin) D. CA-125 (cancer antigen 125)
C
51. Patients with Cushing's disease typically exhibit: A. Decreased plasma 17-hydroxysteroid concentration B. Decreased urinary 17-hydroxysteroid excretion C. Serum cortisol overproduction D. Decreased cortisol secretion rate
C
52. Cholesterol is used by the body for which of the following functions? A. Carrying dietary triglycerides to the cells through the blood B. Maintaining acid-base balance C. Precursor of hormone synthesis D. Major source of fuel for the body
C
58. A deficiency in which of the folowing vitamins is associated with "Night blindness"? A. Thiamine B. Vitamin C C. Vitamin A D. Vitamin D
C
67. When collecting a specimen for vitamin A, which of the following special precautions needs to be taken? A. Keep specimen at body temperature (37° C) B. Chill the specimen in an ice bath C. Protect the specimen from light D. There are no special precautions required
C
68. Vitamin D is controlled by which hormone in a negative feedback loop? A. Calcitonin B. Calcium C. PTH D. TSH
C
70. Cyclosporine and tacrolimus (both immunosuppressive drugs) have multiple therapeutic ranges, why? A. There is no therapeutic range established for either. B. Because of the slow uptake of the medications by tissues. C. Because both drugs have ranges dependent on the organ transplanted and the time after transplantation. D. Because of the short half-lives of the drugs.
C
72. How long does it take for plasma concentrations to reach steady state when a patient's dose is given at intervals of the drug's half-life? A. One half-hour B. Two-half lives C. 5-7 half-lives D. 10-12 half-lives
C
74. A patient suffering from Celiac disease and Crohn disease (both inflammatory conditions of the GI tract) is given a new oral medication that has a narrow therapeutic window. Which of the following would be true? A. An oral medication is never effective for a patient that has these diseases. The drug must be given through IV. B. Toxicity in this patient is not likely since most of the drug won't be absorbed. C. Therapeutic drug monitoring (TDM) would be helpful to see how much drug has been absorbed. D. Serum drug levels obtained 15 minutes after the oral dose should confirm the drug was absorbed.
C
77. Which of the following statements regarding trough level in therapeutic drug monitoring is true? A. Trough level is assessed by collecting a blood sample after a dose of the drug is given (at a specified time). B. Trough level is the point at which the drug is highest in the patient's body. C. Trough level is the point at which the drug is lowest in the patient's body. D. Trough level is assessed by collecting a urine sample right after the next dose of the drug is given.
C
82. Currently the MOST common method for the confirmation of serum barbiturates is: A. Immunoassay B. Thin-layer chromatography C. Gas-liquid chromatography, mass spectrometry D. Ultraviolet absorption spectroscopy
C
86. Which of the following medications is known to cause Reye's Syndrome in children? A. Acetaminophen B. Ibuprofen C. Acetylsalicylic acid D. Morphine
C
87. The De Ritis ratio is the calculation of AST/ALT and is used for evaluating liver disease. What should the ratio be when ethanol-related liver disease is expected? A. <1.0 B. 1.0 -2.0 C. >2.0 D. The De Ritis ratio is not used for liver disease
C
88. Which one of the following statements about lead poisoning is false? A. While lead distributes to all tissues, the central nervous system, kidney, and bone marrow are particularly susceptible to lead toxicity B. Whole blood lead measurement is the best test for detecting lead toxicity C. Serum lead level is a good inexpensive screening test for lead toxicity D. Lead levels below 5 µg/dL in children do not prompt ongoing monitoring
C
98. What blood alcohol concentration has been established as the statutory limit for operation of a motor vehicle in the United States? A. 0.8 mg/dL B. 8 mg/dL C. 80 mg/dL D. 800 mg/dL
C
99. Thin-layer chromatography is particularly useful as a tool in the identification of: A. Steroids B. Enzymes C. Drugs D. Hormones
C
2. The measurement of 17-ketosteroids (17-KSs) in urine is performed to assess PRIMARILY which organ(s)? A. Testes B. Adrenal cortex C. Testes and adrenal cortex D. Anterior pituitary
C testes and adrenal cortex
3. Which assay is performed to diagnose congestive heart failure (CHF)? A. Homocysteine B. hs-CRP and Ischemia Modified Albumin C. B-type natriuretic peptide (BNP) D. cTnI and cTnT
C. B-type natriuretic peptide (BNP)
17. Which of the following hormones is mainly responsible for the entry of glucose into the cell for energy production? A. Epinephrine B. Glucagon C. Cortisol D. Insulin
D
18. Circulating organic iodine is found primarily in the form of: A. Triiodothyronine B. Parathyroid hormone C. Thyroglobulin D. Thyroxine
D
28. Zollinger-Ellison syndrome is characterized by a large (usually 20-fold) elevation of: A. Cholecystokinin B. Pepsin C. Glucagon D. Gastrin
D
40. Which adipokine is decreased in obesity, is anti-inflammatory, and increases insulin sensitivity? A. Leptin B. Resistin C. TNF-a D. Adiponectin
D
48. The immunoassay procedure for serum hCG utilizes antisera against which subunit of hCG? A. Alpha B. Gamma C. Epsilon D. Beta
D
55. A patient in renal failure is seen for blood work. What would you expect the serum calcium and phosphorus levels to be in this patient? A. Increased calcium and phosphorus levels B. Decreased calcium and phosphorus levels C. Increased calcium but decreased phosphorus levels D. Decreased calcium but increased phosphorus levels
D
57. A deficiency in which of the folowing vitamins is associated with "rickets"? A. Thiamine B. Vitamin C C. Vitamin A D. Vitamin D
D
60. What would the following Schilling test results indicate: Part I: 2% excretion of radioactive vitamin B12 (normal: 5-35%)Part II: 8% excretion of radioactive vitamin B12 after intrinsic factor was given with vitamin B12 (normal: 7-10%). A. Tropical sprue B. Transcobalamin deficiency C. Folic acid deficiency D. Pernicious anemia
D
64. A deficiency in which of these vitamins leads to increased clotting time and may result in hemorrhagic disease? A. Riboflavin B. Pyridoxine C. Vitamin C D. Vitamin K
D
76. Which of the following drugs is used to treat congestive heart failure? A. Disopyramide B. Quinidine C. Procainamide D. Digoxin
D
11. Which assay, using 24-hour urine, is considered the BEST single screening test for pheochromocytoma? A. Catecholamines B. Vanillylmandelic acid (VMA) C.Homovallic acid (HVA) D. Metanephrines
D Metanephrines
12. Each of the following hypothalamic hormones is correctly matched with the anterior pituitary hormone that it releases EXCEPT: A. TRH --> TSH B. GnRH --> LH and FSH C. CRH --> ACTH D. GHRH --> Oxytocin
D. GHRH --> Oxytocin
13. Fluorometers are designed so that the path of the excitation light is at a right angle to the path of the emitted light. What is the purpose of this design? A. Prevent loss of emitted light B. Prevent loss of the excitation light C. Focus emitted and excitation light upon the detector D. Prevent incident light from striking the detector
D. Prevent incident light from striking the detector