Carbohydrates and Diabetes - Lab Tests and Concepts (VOCABULARY Flashcards)

Vocabulary flashcards covering key carbohydrate concepts, common tests for carbohydrates, and diabetes-related terms from the lecture notes.

Carbohydrate

Organic compounds with formula Cm(H2O)n, containing C, H, O in ~2:1 H:O. Includes monosaccharides, disaccharides, oligosaccharides, and polysaccharides; storage polysaccharides (starch, glycogen) and structural polysaccharides (cellulose, chitin); ribose and deoxyribose in RNA/DNA.

Monosaccharide

Simple sugar; the basic building block of carbohydrates; cannot be hydrolyzed into smaller sugars.

Disaccharide

Carbohydrate composed of two monosaccharide units linked by a glycosidic bond.

Oligosaccharide

Short chain of a few monosaccharide units.

Polysaccharide

Long polymer of monosaccharides; used for energy storage (starch, glycogen) or structure (cellulose, chitin).

Starch

Storage polysaccharide in plants.

Glycogen

Storage polysaccharide in animals.

Cellulose

Structural polysaccharide in plants.

Chitin

Structural polysaccharide in arthropods.

Glycoprotein

Protein with carbohydrate groups; common in membranes and extracellular matrices.

Lipopolysaccharide

Lipid-carbohydrate component of outer membrane in Gram-negative bacteria.

Ribose

5-carbon aldose sugar; component of coenzymes and backbone of RNA.

Deoxyribose

5-carbon sugar lacking one oxygen; component of DNA.

RNA

Ribonucleic acid; polymer with ribose sugar; carries genetic information for protein synthesis.

DNA

Deoxyribonucleic acid; stores genetic information.

Ketose

Sugar containing a ketone group; dehydrates rapidly with Seliwanoff’s reagent.

Aldose

Sugar containing an aldehyde group.

Seliwanoff’s Test

distinguishes ketoses from aldoses using resorcinol-HCl; ketoses give cherry-red quickly; differentiates monosaccharides from disaccharides.

Molisch’s Test

General test for carbohydrates; purple ring at the interface of two layers indicates presence of carbohydrates.

Bial’s Orcinol Test

Detects pentoses and pentosans; blue-green precipitate forms with orcinol in ferric chloride/HCl; prolonged heating can give false positives.

Pentose

Five-carbon sugar (e.g., ribose).

Pentosan

Polysaccharide composed of five-carbon sugar units.

Benedict’s Test

Qualitative test for reducing sugars; color change from blue to brick-red varies with sugar amount.

Barfoed’s Test

Tests for monosaccharides; brick-red precipitate forms within minutes; uses copper(II) acetate in acetic acid.

Fehling’s Test

Tests for reducing sugars (polyhydroxy aldehydes); uses Cu2+ tartrate complex; brick-red precipitate indicates a positive result.

Tollens’ Test

Tests for aldehydes (including aldoses); silver mirror forms; uses silver diamine complex.

Reducing Sugar

Sugars that can act as reducing agents in redox reactions; have a free anomeric carbon.

Non-Reducing Sugar

Sugars without a free anomeric carbon and thus do not reduce Cu2+ under test conditions (e.g., sucrose in many contexts).

Sucrose

Disaccharide (glucose + fructose) commonly non-reducing due to no free anomeric carbon.

Diabetes Mellitus

Chronic disease where the body cannot effectively use insulin or does not produce enough insulin; leads to hyperglycemia and long-term complications.

Insulin

Hormone regulating blood glucose; promotes cellular uptake of glucose; deficiency or resistance leads to hyperglycemia.

Hyperglycemia

Elevated blood glucose level.

Type 1 Diabetes

Autoimmune, insulin-deficient diabetes; typically early onset; requires insulin therapy.

Type 2 Diabetes

Most common form; insulin resistance or inadequate insulin production; linked to obesity and lifestyle.

Type 3c Diabetes

Pancreatogenic diabetes; secondary to pancreatic disease.

Gestational Diabetes

Diabetes that develops during pregnancy and may resolve after birth; requires monitoring.

HbA1c (Hemoglobin A1c)

Long-term measure of blood glucose control over ~2–3 months; percentage of glycated hemoglobin; gold standard in monitoring diabetes.

Fasting Blood Sugar (FBS)

Blood glucose level after an 8–12 hour fast; used to diagnose diabetes/prediabetes and monitor treatment.

Glucose Oxidase Test

Enzymatic method to quantify glucose using glucose oxidase; produces hydrogen peroxide and chromogen color change; widely used in clinics and home devices.

Polydipsia

Increased thirst.

Polyuria

Frequent urination.

Polyphagia

Excessive hunger.