What information does the G6PD assay suggest regarding the inheritance of this enzyme abnormality?

G6PD gene is on the X chromosome

Why does G6PD deficiency seem to have the most adverse effect on red blood cells?

The pentose phosphate pathway is the only source of NADPH in the red blood cell

The pentose phosphate pathway, sometimes referred to as the pentose phosphate shunt takes place in the-

cytosol

Unconjugated bilirubin is poorly soluble in aqueous solution and is transported in plasma by-

bounding to albumin

Which of the following pathways is considered to be an ANABOLIC pathway that produces new carbohydrate molecules?

Pentose phosphate pathway

What is the purpose of the pentose phosphate pathway?

Synthesis of ribose, nucleotides, NADPH

Which one of the following gas is produced as a direct result of heme catabolism to bilirubin IXa?

CO (carbon monoxide)

Pentose phosphate pathway can occur in-

RBC cells, nerve cells, heart cells, adipose tissue

What percent of G6P can be OXIDIZED to CO2 in the pentose pathway?

100%

An elderly couple living in the suburbs of Hanover, New Hampshire, was snowbound for several days in their home during a blizzard, during periods of electrical outage they relied on an unvented gas heater to warm one room in their home where they stayed throughout the blizzard. As soon as the roads cleared, their granddaughter came to check on them and found them disoriented, complaining of headache, fatigue, and nausea, and breathing and walking with a stumbling gait.

Lab data shows a remarkably increased carboxyhemoglobin level in the blood . The best explanation for this finding is that CO has which of the following affects?

It competitively displaces O2 from oxyhemoglobin

Which of the following treatment strategies is the most effective remediation for CO poisoning?

Removal from CO source and administration of 7% CO2 and 93% O2

In addition to forming carboxyhemoglobin, the toxic effects of CO include inhibition of which of the following enzymes involved in the oxidation-reduction reactions?

Cytochrome C oxidase

Myoglobin contains hemes, pigments responsible for the color of red meat. The color that meat takes is partly determined by the degree of oxidation of the myoglobin. In fresh meat, the iron atom is the ferrous state bound to an O2. Meat cooked well done is brown because the iron atom is now in the ferric oxidation state, having lost an electron. Hormel and Cargill are both reported to use a meat-packing process, that artificially induced pink color meat that can persist for up to one year. Pink color meat is usually associated in consumers minds with fresh meat. The meat treated this way has been in the consumer market since 2003. How do Hormel and Cargill have fooled consumer for so long?

If meat has been exposed to carbon monoxide, it will remain pink because the iron atom is bound it CO, and CO keeps the iron atom in Fe2+ (ferrous state)

Administration of 5-7% of CO2 to the O2 is sometimes used to treat CO poisoning. The advantage of CO2 addition is _________ and the disadvantage of CO2 addition is __________.

stimulates ventilation, the reduction of O2 delivery

Why is HbF (fetal hemoglobin) suboptimal postpartum for delivery of O2?

Because it has a higher affinity for O2, which limits the quantity of O2, delivered to the tissues

After releasing O2 at the tissues, hemoglobin transports-

CO2 and protons to the lungs

Why does HbF have higher affinity for O2 that HbA?

BPG binds more weakly to HbF than to HbA

Mutations that favor the R state (hemoglobin Chesapeake) leads to-

polycythemia

The genetic defects known as thalassemias result from the partial or total absence of-

a (alpha) or B (beta) chains of hemoglobin

Inhibitions of oxidative phosphorylation by cyanide ion leads to increases in which of the following?

lactic acid in blood causing acidosis

The reduction half-reaction in the last step of the electron transport chain is-

O2+4e- + 4H+ --> 2H2O

Which of the following procedures best describes the emergency intervention for cyanide poisoning?

Treatment with thosulfate to form thiocyanate

A 16-month-old girl was found to have ingested approximately 30mL of an acetonitrile-based cosmetic nail remover. When she vomited 15 minutes post ingestion, the poison control center was contacted; however, no treatment was recommended because it was confused with an acetone based nail polish remover. The child was put to bed at her normal time, which was 2 hours post ingestion. Respirtory distress dveleoped sometime after the child was put to bed, and she was found dead the next morning.

Inhibition of which of the following enzymes was most likely cause of this child's death?

cytochrome c oxidase

Respitory distress is induced when exposed to rotenone because it inhibits the complex that catlyzes which of the following?

Electron transfer from NADH to coenzyme Q

Which of the follwing statemeents is correct?

Nitrate ion (NO2) is administered to convert some oxyhemoglobin (HbO2(Fe2+)) to methemoglobin (met-HbOH(Fe3+) in cyanide treatment.

True or False: For every pair of electrons passing down the chain from NADH or FADH2, 2H+ are pumped across the membrane by complex IV

True

The ability to exist in both an oxidized and a reduced state is a chrateristic of -

electron carriers

NADH can not penetrate the mitochondrial membrane, but it is produced continously in the cytosol by glycolysis. How do we transport this NADH from cytosol to mitochondria?

malate-shuttle and glycero-phosphate shuttle

The major metabolic consequence of disturbance of the electron transfer in mitochondria is which of the following?

decreased regeneration of NAD+

FMN and FAD are dervived from the vitamin riboflavin (B2) and are called flavin coenzymes. Coenzymes are small organic molecules that are mostly derived from vitamins and are involved in enzyme catalyzed reactions. Sources of riboflavin are milk,cheese,leaf vegtables, liver, kidneys, mushrooms, and almonds.

If someone has a B2 deficiency, which one of the follwoing energy pathways are most likely effected by this deficiency?

TCA cycle and ETC

Genetic defects in fatty acid oxidation can account for severe weakness during exercise and up to 10% of sudden infant deaths, Could people with this defect produce glucose by gluconeogenesis?

No, because they would struggle to produce pyruvate which is needed for gluconeogenesis.

In discussions of nutrition, energy is often expressed in units of calories. In this context a calorie means-

1000 kilocalories

oxidative pathways are-

catabolic (breaking down)

ATP production in RBC is totally dependent upon glucose and anareobic glycolysis because there are no mitochondria (no TCA cycle operating) in these cells. Why are there no mitochondria in RBC?

Lack of mitochondria makes red blood cells more flexible so they can pass through the capillary better.

Which of the following options has the highest to lowest caloric content (kcal/g)

Fat>Alcohol>Carbohydrate=Protein

The major carbohydrates in the diet are-

starches, sucrose, glucose, and fructose

Conversion of pyruvate to acetyl CoA is an irreversible reaction, acetyl CoA cannot be converted to pyruvate then to OAA. In the future, we may have a mutation in the enzyme that converts pyruvate to acetyl CoA. If acetyl CoA could be converted to pyruvate and then to OAA, would we still need to have glucose in our diet for the production of energy?

No, because we would be able to synthesize glucose effectively from fatty acids through this pathway.

Nicotinamide adenine dinucleotide (NAD) is derived from niacin (B3 vitamin) and is a coenzyme used for many dehydrogenases. If someone has niacin deficiency, what kind of symptoms can you expect this person to have?

Fatigue, Anemia, Dementia

Imagine a mutation happens to an individual and she ends up having a channel that lets H+ leak into the matrix of the mitochondria. What would be the consequence of the H+ leak?

The ETC would generate little or no ATP and all the H+ energy will convert to heat.

What hormone(s) raises cAMP?

epinepherine, glucagon

Why is the glycolytic pathway not 100% reversible

because it has 3 IRREVERSIBLE steps that are important to make pyruvate

What steps are irreversible in glycolysis?

Hexokinase, phosphofructokinase, pyruvate kinase

During an extended fast , acetyl CoA is converted into

ketone bodies

What is the primary source of glucose after fasting for a few hours?

the liver

Glucose uptake outside the liver is regulated by what hormone?

Insulin

What is the level of glucose and insulin in diabetic ketoacidosis?

Glucose is HIGH, and Insulin is LOW

What hormone is the opposite of glucagon?

Insulin

What molecule is used in glycogen synthesis, glycolysis, and the pentose phosphate pathway?

glucose-6-phosphate

In the first step of glycolysis, how many ATPs are used to phosphorylate glucose?

1 ATP

What are the relaxation steps in the sliding filament model?

Ca2+ releases from troponin, actin and myosin do not react, Ca2+ returns to SR

What drug is administered to treat malignant hyperthermia?

dantrolene

Why does rigor mortis occur?

due to the depletion of ATP which prevents myosin heads from detaching from actin

Which troponin binds to calcium?

troponin C

Which bands shorten during contraction

H and I bands

What breaks when hemoglobin does a conformational change?

salt bridges

In what scenario would myoglobin release O2?

excessive weight training

Hemoglobin __________ oxygen

transports

Myoglobin _________ oxygen

stores

What happens when carbon monoxide binds to hemoglobin in the red blood cells?

it forms carboxyhemoglobin (COHb) which reduces the hemoglobin ability to carry oxygen

What promotes hemoglobin to transition from a high-oxygen-affinity state to a low-oxygen-affinity state?

2,3-BPG

If there is no oxygen in hemoglobin, what state is it in

T (tense) state

If there is oxygen present in hemoglobin, what state is it in?

R (relaxed) state

What is the function of the enzyme carbonic anhydrase?

it dehydrates carbonic acid and converts it to CO2

How many helices does myoglobin have?

8