Chemistry Exam 4

Glycogen

What is the body’s storage form of glucose?

Glucose, Fructose, Galactose

The three primary monosacchrides

Sucrose, maltose, lactose

The three primary disaccharides

Glucose

This monosaccharide is common to all three disaccharides

Monosaccharides

Poly- and disaccharides must be broken down to ___________ to be absorbed

Hexose monophosphate shunt

In the cells, glucose is converted to G6P to form NADPH in this mechanism via hexokinase

Glycogenesis

The formation of glycogen

Glycogenolysis

The breakdown of glycogen into glucose

Glycolysis

The breakdown of glucose to release energy

Gluconeogenesis

The formation of glucose from non-carbohydrate precursors (amino acids, lactate, fatty acids)

Lipogenesis

The conversion of glucose to fatty acids

Glycogenesis, lipogenesis, glycolysis

Insulin promotes what processes?

Glycogenolysis, glyconeogenesis

Glucagon promotes what processes?

Epinephrine, cortisol, growth hormone

These hormones are released when blood glucose is low

10% lower

Whole blood glucose is __________ than plasma glucose

G6PD

Hexokinase measures glucose using _______

Peroxidase

Glucose oxidase measures glucose using ________

Endogenous insulin

C-peptide is created when what form of insulin is used?

DKA

High lactic acid, anion gap, and serum osmolality

HONK

Glucose >1000mg, increased BUN

24-28 weeks

When is gestational diabetes tested?

von-Gierkes

In this disease, G6P is deficient, leading to a type 1 glycogen storage issue

Galactose, fructose, pentose, or lactose

When the urine glucose is NEGATIVE, and the Clinitest is POSITIVE, what is causing the positive result?

Glucose

When the urine glucose is POSITIVE, and the Clinitest is POSITIVE, what is causing the positive result?

Lipoproteins

Lipids must be bound to ______ to be transported in the body

Beta-oxidation

What process converts lipids to ketone bodies during starvation?

Triglycerides

How are fatty acids stored in the body?

Glycerol + 3 fatty acids

Composition of a triglyceride

VLDL

Transports ENDOGENOUS triglycerides

Chylomicrons

Transports EXOGENOUS triglycerides

Cholesterol

What lipid can be converted into bile acids and salts in the liver?

LCAT

Conjugates fatty acids to cholesterol in the PLASMA

ACAT

Conjugates fatty acids to cholesterol in the CELLS

ApoB48

Primary apoprotein for chylomicron

Exogenous triglycerides from intestines to cells

Chylomicron transports?

Endogenous triglycerides to tissues

VLDL transports?

ApoB-100

The primary apoprotein for VLDL

ApoB-100

The primary protein for LDL

Cholesterol to tissues

LDL transports?

Protein from cells to liver

HDL transports?

ApoA-1

Primary apoprotein for HDL

Cholesterol, Triglycerides, LDL, HDL

Tests in a lipid panel

LDL

What test in a lipid panel is calculated?

Triglycerides

What test is most affected when a patient does not fast?

Abell-Kendall

The reference method for measuring cholesterol

Ultracentrifugation

The reference method for measuring HDL

LDL=(total cholesterol)-(HDL)-(trig/5)

Friedewald Equation

ApoB-100

What apoprotein is elevated in all cases of combined hyperlipoproteinemia?

Orange tonsils, xanthomes

Symptoms of hypoalphalipoproteinemia

Acanthocytes, poor growth, fatty liver

Symptoms of Abetalipoproteinemia

ApoA

HDL is affected by this deficient apoprotein in Hypoalphalipoproteinemia

ApoB

LDL is affected by this deficient protein in Abetalipoproteinemia

ApoB-100 receptor

This deficiency causes hypercholesterolemia

Lipoprotein lipase or ApoC

This deficiency causes Hypertriglyceridemia

Triglycerides >400mg/dL

Invalidation for HDL and the Friedewald equation

Fe2+

This form of iron is ingested, absorbed from the intestines, and is incorporated into hemoglobin

Fe3+

This form of iron is ingested, binds to transferrin and ferritin, and is associated with methemoglobin

Apotransferrin

What protein is responsible for transporting iron from the intestines to the tissues?

Transferrin

Apotransferrin+Fe3+——→

Ferritin

Major storage form of iron in the liver

Hemosiderin

When iron is exceeded in storage in the liver, it is converted to ___________

Measurement of iron

Iron in the Fe 3+ state is bound to transferrin then converted into Fe2+ to bind with chromagen in the test

Measurement of Ferritin

Stored iron

Measurement of transferrin saturation

Ratio of Iron to TIBC

Measurement of TIBC

Fe 3+ is added until all transferrin is saturated then excess Fe 3+ is removed and serum Iron is measured again

.007

Transferrin= TIBC TIMES (?)

Iron deficient anemia

Low iron, elevated Transferrin, Low ferritin, low % saturation, high TIBC

Anemia of Chronic Disease

Low iron, Low transferrin, high ferritin, low %saturation, low TIBC

Hereditary Hemochromatosis

High iron, low transferrin, high ferritin, high % saturation, low TIBC

Ferritin

Which parameter is affected first in Iron Deficiency Anemia?

Protoporphyrin, Coproporphyrin, Uroporphyrin

Three clinically significant porphyrins

Porphyrin ring

Cyclic compound that binds Fe2+ or Fe 3+ to form heme

Erythropoietic Porphyria

Overproduction of heme precursors in the bone marrow

Hepatic Porphyria

Overproduction of heme precursors in the liver

Cutaneous Porphyria

Photosensitivity, skin manifestations of porphyria

Acute porphyria

Sudden attack of pain and neurological symptoms

ALA-dehydrogenase, ferrochelatase

What enzymes are inhibited by lead exposure?

Symptoms of Lead Poisoning

Elevated urinary ALA, Coporphyrin III, Erythrocyte Protoporphyrin IX

Bilirubin

Breakdown product of Heme

Biliverdin

In the macrophage, Heme is broken down into ______

Unconjugated (indirect) bilirubin

Biliverdin is reduced to ______ before being bound to albumin and transported to the liver

Albumin

Unconjugated (indirect) bilirubin must be bound to _____ to be transported to the liver from the macrophage

UDP-glucuronyl transferase

This enzyme converts unconjugated (indirect) bilirubin to conjugated (direct) bilirubin in the liver

Water soluble

Conjugated bilirubin is _____ (water soluble or insoluble)

Water INSOLUBLE

Unconjugated (indirect) bilirubin is ______ (water soluble or insoluble)

Urobilinogen

Conjugated bilirubin that is excreted through feces mostly

>2-3 mg/dL

Jaundice bilirubin levels

>15 mg/dL

Kernicterus bilirubin levels

Prehepatic

Jaundice due to increased RBC lysis

Prehepatic Jaundice Levels

High indirect bili

normal to HIGH direct bili

no urine bilirubin

high urobilinogen

Hepatic-retention Levels

High indirect bili

normal to LOW direct bili

no urine bilirubin

Normal to high urobilinogen

Hepatic-regurgitation Levels

High indirect bili

normal direct bili

HIGH URINE BILIRUBIN

normal to high urobilinogen

Post-hepatic jaundice Levels

Normal indirect bilirubin

high direct bili

HIGH urine bilirubin

normal urobilinogen

Crigler-Najjar syndrome (Retension disorder)

Deficient or absent UDP-glucuronyl transferase disease

Gilbert Syndrome (Retension disorder)

Bilirubin uptake to hepatocytes is decreased disease

Lucey-Driscoll Syndrome (Hepatic Disorder)

Circulating inhibitor of bilirubin conjugation disease

Regurgitation Jaundice

Inability of bilirubin to leave the liver resulting in conjugated bilirubin leaking out of the hepatocytes

Unconjugated (indirect) bilirubin

Major form of bilirubin present in neonates with jaundice

Negative/Absent

How does post-hepatic jaundice affect urobilinogen levels?

Alcohol

Accelerant in Diazo method