intro to carbo Flashcards
major food source and energy supply for the body, found in connective tissues and nucleic acids
Carbohydrates
where glycogen is primarily stored in the body
liver and muscle
condition characterized by an increased level of glucose and is commonly seen in diabetic patients
Hyperglycemia
T/F: Hyperglycemia can be caused by factors like pancreatectomy, stress, and pregnancy.
True
T/F Hyperglycemia can also be caused by pregnancy, dehydration, and abnormal insulin receptors.
T
condition with decreased plasma glucose level and commonly seen in diabetic patients who inject insulin
Hypoglycemia
Severe Hyperglycemia occurs primarily in ___% of diabetics every year
10
caused by an imbalance of hormones and leads to chronic hyperglycemia
Diabetes mellitus
Which of the following is NOT a cause of hyperglycemia?
A) Hemochromatosis
B) Dehydration
C) Insulin overdose
D) Pancreatectomy
Insulin overdose – causes hypoglycemia.
hormone produced by the β-cells of the pancreatic islets of Langerhans and promotes glucose entry into cells
Insulin
hormone produced by the α-cells of the pancreatic islets of Langerhans which is responsible for increasing plasma glucose levels
glucagon
T/F: Insulin is the only hormone that decreases glucose levels and functions as a hypoglycemic agent.
T
process insulin stimulates to convert glucose into glycogen for storage in the liver and muscles?
Glycogenesis
process in wc glycogen is broken down into glucose in response to glucagon
Glycogenolysis
process where insulin stimulates the synthesis of fatty acids and triglycerides from glucose
Lipogenesis
process that insulin inhibits to prevent the release of glucose from the liver?
Glycogenolysis
T/F Insulin inhibits glycogenolysis, while glucagon stimulates it.
T
hormone responsible for increasing plasma glucose levels through glycogenolysis and gluconeogenesis?
Glucagon
Which of the following processes is NOT regulated by insulin?
A) Glycolysis
B) Glycogenolysis
C) Lipogenesis
D) Glycogenesis
B) Glycogenolysis – regulated by glucagon
process where glucose is formed from non-carbohydrate sources such as amino acids and glycerol?
Gluconeogenesis
T/F Glycolysis is the breakdown of glucose to form products such as lactate, pyruvate, and ATP.
T
type of samples routinely used to measure glucose in the body
serum/plasma, whole blood, urine, csf
Why should serum or plasma be separated from blood cells as soon as possible when measuring glucose?
Blood cells continue to metabolize glucose, lowering glucose levels in the specimen.
T/F Glucose levels in whole blood are approximately 11% lower than in serum or plasma.
T
Odd One Out: Typical body fluid for glucose measurement
A) Serum
B) Plasma
C) Saliva
D) Urine
C) Saliva - mlamang
Venous blood glucose is approximately _____ lower compared to capillary blood glucose
7 mg/dl
T/F: CSF glucose levels are approximately 60-70% of plasma glucose levels
T
when should fasting blood glucose be obtained + how long should patient fast?
morning after 8-10 hrs of fasting
glucose levels in an uncentrifuged blood specimen kept at room temperature decreases by ___ per hr
5-10 mg/dl
T/F: If an uncentrifuged blood specimen is refrigerated, the glucose level decreases by approximately 3 mg/dL per hour.
F - 2 mg/dl
Odd One Out: Factor that affects fasting blood glucose
A) Diurnal variation
B) Time of fasting
C) Temperature
D) Content of last meal
D) Content of Last Meal – Fasting blood glucose requires no food intake for 8-10 hours.
Blood for CSF glucose levels should be obtained ___ hours before the spinal tap
1-2 hrs
inhibits in vitro glycolysis, stabilizing glucose for up to 3 days at room temperature.
Sodium Fluoride Tube
Odd One Out: Characteristic of a sodium fluoride tube
A) Inhibits in vitro glycolysis
B) Bacterial contamination increases glycolysis rate
C) Stabilizes glucose for 3 weeks
D) Best way to minimize glycolysis is to separate plasma from cells
C) Stabilizes glucose for 3 weeks – It stabilizes glucose for up to 3 days.
principle of the Alkaline Copper Reduction Method
Reduction of cupric ions to cuprous ions in a hot alkaline solution by glucose.
T/F The Alkaline Copper Reduction Method is specific for glucose.
F – High levels of ascorbic acid or other reducing agents can cause false positives.
chemical method most commonly used for glucose determination
Nelson-Somogyi Method
In the Folin-Wu Method, glucose reduces cupric ions to form what final product?
Phosphomolybdenum blue
end product of the Neocuproine Method and color
Cuprous-neocuproine complex; yellow to yellow-orange - indicating glucose presence
Odd One Out: Involves a yellow-to-orange color change
A) Neocuproine Method
B) Benedict’s Method
C) Hagedorn-Jensen Method
C) Hagedorn-Jensen Method – based on inverse colorimetry and does not use yellow-to-orange color changes.
The Benedict’s Method uses _____ as stabilizing agents.
tartrate and citrate
color indicates a high glucose level in the Benedict’s Method
Brick red
method uses the principle of reducing ferricyanide to ferrocyanide in hot alkaline solution
Alkaline Ferric Reduction Method
how is glucose concentration measured in the Hagedorn-Jensen Method
proportional to the decrease in absorbance, using inverse colorimetry.
measures the ability of primary aromatic amine acid to condense with glucose’s aldehyde group to form glycosylamines
Condensation Method
Odd One Out: Interfering substance in the Condensation Method
A) Galactose
B) Uric acid
C) Mannose
D) Aldopentose
B) Uric acid – interferes with enzymatic methods, not condensation methods.
end product of the Ortho-Toluidine Method and its final color
N-glucosylamine; bluish green.
three major enzymatic methods for glucose determination
Glucose oxidase
Hexokinase
Glucose dehydrogenase
enzyme used in the Glucose Oxidase Method – one of the most common for glucose determination?
Glucose oxidase
GLUCOSE OXIDASE METHOD aka
Saifer Gernstenfield method
T/F The Glucose Oxidase Method is prone to errors caused by other reducing substances, such as ascorbic acid.
T
Which of the following is NOT a common cause of falsely decreased glucose in the Glucose Oxidase Method?
A) Uric acid
B) Ascorbic acid
C) Glutathione
D) Ferricyanide
D) Ferricyanide – part of the Hagedorn-Jensen Method.
reaction of Trinder reaction, and in which glucose determination method is it used?
coupled reaction used in the Glucose Oxidase Method
T/F: Hexokinase is a highly specific enzyme for glucose measurement because it phosphorylates glucose into glucose-6-phosphate.
T
glucose determination method monitored by the disappearance of oxygen using an oxygen electrode or the consumption of hydrogen peroxide
Glucose Oxidase Method
Odd One Out: Causes of falsely elevated glucose in the Glucose Oxidase Method
A) Bleach
B) Ascorbic acid
C) Strong oxidizing compounds
D) Overexposure to air
B) Ascorbic acid – falsely decreased glucose
reference standard method for glucose determination and is considered more accurate than the glucose oxidase method
Hexokinase Method
enzyme used in the Hexokinase Method for glucose determination?
Hexokinase
absorbance measured in the Hexokinase Method increases at what wavelength
340 nm
T/F Hexokinase Method can give false high results due to gross hemolysis or increased bilirubin.
F - low
Odd One Out: Factors that causes false low results (Hexokinase Method)
A) Gross hemolysis
B) Increased bilirubin
C) Increased ATP concentration
C) Increased ATP concentration – ATP is a necessary substrate in the reaction, not a cause of false results.
what enzyme converts α-D-glucose to β-D-glucose in the Glucose Dehydrogenase Method
Mutarotase
compound that forms a blue color in the Glucose Dehydrogenase Method after NADH reacts with MTT and diaphorase?
Formazan
T/F: The Glucose Dehydrogenase Method is more accurate than the Hexokinase Method for glucose determination.
F – Hexokinase Method is the reference standard and more accurate.
formula to calculate the glucose concentration of a control sample
conc_sample=(conc_std)×( Abs_sample/ Abs_std)
formula used to calculate the glucose concentration of a sample?
conc_sample=(conc_std)×(Abs_sample / Abs_std)
T/F: To calculate the glucose concentration of CP (control positive), you use the formula:
conc_CP=conc_std×(Abs_std / Abs_CP)
F - (Abs_CP/ Abs_std)
reference range for glucose concentration in conventional units
70-110 mg/dL
T/F: The reference range for glucose in SI units is 3.9-6.1 mmol/L.
T
conversion factor used to convert glucose concentration from mg/dL to mmol/L?
0.0556
Odd One Out: Increased glucose levels
A) Diabetes mellitus
B) Starvation
C) Pancreatitis
D) Renal failure
B) Starvation – decreased glucose levels
diseases commonly associated with increased glucose levels
Diabetes mellitus, Pancreatitis, Pituitary or thyroid dysfunction, Renal failure, and Liver disease
T/F: Hyperinsulinemia and insulin-induced hypoglycemia cause decreased glucose levels.
T
Odd One Out: Decreased glucose levels
A) Hyperinsulinemia
B) Neoplasms
C) Liver disease
D) Starvation
C) Liver disease – Liver disease leads to increased glucose levels.
condition characterized by excess insulin leading to hypoglycemia and low plasma glucose levels
Hyperinsulinemia
T/F Neoplasms can result in increased glucose levels.
F - decreased
diabetic patient who injects insulin have 1 or 2 episodes of ___ per week
symptomatic hypoglycemia
what should be added in nelson somagyi method when preparing Protein-Free Filtrates to remove saccharoids
Barium sulfate (BaSO4)
Nelson Somagyi involves the conversion of glucose to what color
arsenomolybdenum blue
