Unit 2 - my exam

When Ca++ increases in muscle cells, muscle contracts and all of the following happen EXCEPT:

:Isocitrate dehydrogenase and alpha-keto glutarate dehydrogenase are allosterically activated by increases in NADH

The ribonucleic reductase is regulated at both an activity site and a substrate substrate specificity site. Which of the following compounds must always rebound to the activity site Foran enzyme to be active?

ATP

Which compound must always be bound at the activity site for an enzyme to be active?

ATP

All of the following are part of the Cori Cycle EXCEPT:

ATP is produced by the conversion of lactate to glucose

Dinitrophenol is an uncoupler of the electron transport cahin. The addition of dinitrophenol will have which of the following impacts to the cell?

increased oxygen consumption

Which of the following hormones binds to a receptor tyrosine kinase?

insulin

An individual with a deficiency in Pyruvate stressate dehydrogenase complex (PDC) will have elevated levels of which metabolite after consuming a meal high in carbohydrates?

lactate

Under conditions of anaerobic glycolysis pyruvate is primarily oxidized to which compound:

lactate

Based on the schematic what will the charge be on guanine pH of 10? -2

-2

what will the charge of guanine be at a pH of 10

-2

The majority of energy in ATP is stored within which of the following bonds below?

1

Skeletal muscle does not have the enzyme glucose 6-phosphatase, which is required to dephosphorylate glucose-6-P released during the process of glycogenolysis. As a result of this, glucose 6-P released from muscle glycogen stores is primarily used for which of the following processes?

A ) it enters the glycolytic pathway and is oxidized

NADPH is used by most cells for which of the following processes?

A reducing agent in detoxification reactions

Protein Kinase A? Activated by: glucagon, epinephrine, g-protein

Activated by: glucagon, epinephrine, g-protein inactivated by: insulin

Which of the following hormones will facilitate activation of of protein kinase A?

Activation of G-protein glucagon epinephrine

which of the following digestive enzymes is primarily responsible for digesting large polysaccharides chains into smaller oligosaccharides?

Alpha amylase

Monocytes are unique cells that secrete the cytokine, interleukin-1. Once released, this cytokine will bind a receptor on the outside of the monocytes and regulate its response. In this situation interleukin-1 is best described as which of the following?

An autocrine signal

At physiological pH, guanine will be neutral

At physiological pH, guanine will be neutral

Which of the following compounds or hormones will not facilitate the process of skeletal muscle glycogenolysis?

Ca++

Which of the following is an example mechanical work?

Cleavage of high energy phosphate bond to facilitate muscle contraction

Retenone is an inhibitor of complex 1 in the electron transport chain. Which of the following will not occur as a result of the addition of rotenone?

Decrease Oxidation of FADH2 These things will occur: Decreased production of ATP - Decreased oxygen consumption - Decreased oxidation of NADH

You have identified a mutation in the c subunit in the ATP synthase. The mutation changes the glutamate residue, (that facilitates proton pumping into the mitochondrial matrix), to a glycine. The inability to dissipate the proton gradient will have which of the following impacts on the electron transport chain?

Decreased ATP Synthesis

An individual consumes a breakfast consisting of cereal, eggs, sausage, pancakes and maple syrup. After this meal, which of the following statements best summarizes his metabolic state?

Fructose 2,6 bisphosphate will be elevated

Metabolism of fructose converges with glucose metabolism (glycolysis) and fructose 1-P can enter the glycolytic pathway as which of the following intermediates?

Fructose 6 phosphate

Which of the following intermediates is a feed-forward activator of pyruvate kinase?

Fructose-1-6-biphosphate

Which of the following activators is correctly paired with the enzyme that activates it?

Fructose-2,6-bisphosphate : phosphofructokinase 1 NOT: Glucose-6-phosphate : hexokinase ATP : alpha-ketogluterate dehydrogenase ATP : pyruvate kinase Citrate : citrate synthase

Fructose 1,6 bisphosphate will enhance the activity of which of the following enzymes?

Fructose-6-phosphate

Under conditions when a cell only needs to use the nonoxidative portion of the pentose phosphate pathway to synthesize ribose 5-phosphate, the elevated levels of NADPH in the cell will inhibit which of the following enzymes?

G-6-phosphate dehydrogenase

Which of the following is a monosaccharide?

Galcatose, glucose, fructose

In the liver, the pyruvate dehydrogenase complex (PDC) would be dephosphorylated and active when which of the following compounds or hormones is elevated?

Glucagon

Glucagon will influence the metabolism in the liver, adipose, and skeletal muscle during fasting. Which of the following is consistent with the impact of glycogen?

Glucagon will increase output of glucose by the liver

There are several anaplerotic reactions required to replenish intermediates of the TCA cucle. All of the following compounds can be used for these anaplerotic reactions EXCEPT:

Glucose

Metabolism of galactose converges with glucose metabolism and galactose 1-P will eventually enter the pathways as which of the following intermediates.

Glucose -1- phosphate

Following a meal, fructose 2,6 bisphosphate levels will be elevated in the liver. Under these conditions which of the following will be dephosphorylated and inactive? Glycogen synthase

Glycogen synthase

When the pancreatic beta cells sense an increase in glucose, the release of insulin is facilitated through which of the following mechanisms?

Increase in intracellular calcium

There is a gain of function mutation in the insulin receptor substrate that makes it permanently bound to the insulin receptor. Which of the following may occur as a result of this mutation.

Increase in protein kinase B activity

Which of the following hormones binds to a receptor tyrosine kinase?

Insulin

During aerobic exercise, intracellular calcium increases and which of the following will occur?

Isocitrate dehydrogenase and alpha-keto glutarate dehydrogenase are allosterically activated by increase in calcium

Skeletal muscle does not have the enzyme glucose 6-phosphatase, which is required to dephosphrylate glucose-6-P released during the process of glcogenolysis. As a result of this, glucose 6-P released from muscle glycogen stores is primarily used for which of the following processes?

It enters the glycolytic pathway and is oxidized

Under fed conditions, glucose taken up by the liver is primarily used for which of the following processes?

It is used as a substrate for liver glycogen synthesis

Which of the following statements best describes the action of epinephrine?

It works to mobilized fuels during acute stress

In the red blood cell, glucose can be oxidized to two primary products. One of the oxidation products is ribulose 5-phosphate, and the other is which of the following compounds?

Lactate

Inositol triphosphate (IP3) binds to ____________ channels in the endoplasmic reticulum while diacycerol (DAG) activates ________________.

Ligated Ca2+ channels, the influx of extracellular cations in T-lymphocytes OR protein kinase C

Which of the following tissues uses lactate from the Cori Cycle to make glucose?

Liver

During an overnight fast, which of the following pathways is the primary source of glucose required for the maintenance of blood glucose levels?

Liver Glycogenolysis

Under conditions of strenuous exercise, gluconeogenesis occurs primarily in the _________ using _________ formed in the skeletal muscle.

Liver; lactate

NADH generated in the cytosol must be transported across the mitochondrial membrane in order to be oxidized by the election transport chain. Which of the following shuttles or transporters can be used to facilitate the movement of systolic NADH in to the mitochondria.

Malate-Aspartate shuttle

What is the oxidizing agent in the following reaction?

NAD+

Within the red blood cell, the lack of which of the following compounds can result in execrative hemolysis and jaundice?

NADPH

The oxidation of glucose produces NADH. NADH can be oxidized in the mitochondria and in this process the terminal electron acceptor in the electron transport chain is which of the following compounds?

O2

Certain conditions such as excessive alcohol consumption can increase the ratio of NADH/NAD+ in the mitochondria. This will directly inhibit which of the following enzymes?

PDC (kinase)

Insulin is a peptide hormone secreted by the beta cells of the pancreas in response to elevated levels of blood glucose. Locally, insulin will inhibit the release of glucagon from alpha cells in the pancreas, and it will also impact the metabolism of many peripheral tissues. The actions of insulin are best described as which of the following?

Paracrine and endocrine

Alcoholics: Elevated levels of NaDH will inhibit which?

Pyruate dehydrogenase compound

In an individual with a deficiency in pyruvate dehydrogenase complex (PDC), which of the following reactions would be directly impaired?

Pyruvate ----> acetyl CoA

A thiamine deficiency will result in decreased activity of:

Pyruvate dehydrogenase; transketolase

Which of the following tissues can use glucose, but not fatty acids, as a source of fuel?

RBC

HFI is a rare recessive disorder. Which of the following is not a consequence of this enzyme deficiency?

SM

Which of the following is true regarding single point mutations to a genomic DNA sequence?

Single nucleotide changes to the DNA sequence may have no impact on the primary sequence of a protein

Which of the following enzymes is part of both the TCA cycle and ETC?

Succinate dehydrogenase

Within the red blood cell, NADPH is required for which of the following processes?

The reduction of glutathione

The mechanism of action of the pyruvate dehydrogenase complex (PDC) relies on the use of three prothetic groups in the enzyme active site. Which of the following lists these three groups in the order that they are utilized during the oxidation of pyruvate?

Thiamine pyrophosphate; Lipoate; FAD

In the case of deficiency in phenylalanine hydroxlase which of the following amino acids will become essential:

Tyrosine

When a muscle cell contracts, all of the following will increase glycogenolysis EXCEPT:

WILL NOT: Increased oxidation of alcohol

Prokaryotic genes are organized which contain a series of genes that are regulated by a common promoter. In the case of an inducible operon, the operaon is transcribed:

When the inducer is bound to the repressor

Which of the following statements best describes the action of epinephrine?

d) it works to mobilized fuels during acute stress:

which hormone can enhance glycogenolysis in both liver and muscle?

epinephrine

Besides its role in glycogen synthesis, which of the following directly relies on UDP-glucose?

galactose

After fasting for 6 hours which of the following would be consistent with hormone levels of this individual?

glucagon

which of the following is considered catabolic?

glycogenolysis

Glycogen synthesis and degradation in the liver and muscle is very similar. Which of the following enzymes is not used in both muscle and liver for those metabolic pathways?

hexokinase glucose 6-phosphatase

A substitution mutation occurs in the GRE (glucocorticoid response element) making it unrecognizable to the glucocorticoid receptor. What impact would this have on the transcription of the gene downstream of this element?

lead to death

Hereditary fructose intolerance (HFI) is a rare recessive disorder that is caused by a mutation in the aldolase B gene. As a result of this disorder individuals may have all of the following symptoms EXCEPT:

low blood sugar after fasting

Sickle cell is caused by a single point mutation that changes a glutamic acid to a valine. This type of mutation is best categorized as which of the following?

missense mutation

When glucagon binds its receptor there is an increase in the second messenger, cAMP. cAMP levels can be decreased by which of the following enzymes?

phosphodiesterase

All are enzymes of the pyruvate dehydrogenase complex but:

pyruvate synthase

Which of the following tissues exclusively oxidized glucose under all conditions?

red blood cells, brain

In the malate aspartate shuttle, cystolic oxaloacetate is _____________ to form _______ as a means of moving reducing equivalents across the mitochondrial membrane.

reduced; malate

A 3-year-old boy who presented with generalized hypotonia, severe psychomotor development delay, and severe lactic acidosis following ingestion of a high carbohydrate meal was diagnosed with a deficiency in pyruvate dehydrogenase (X-linked recessive). Supplementation of which vitamin may be beneficial to this individual:

thiamine

The movement of glucose from the intestinal lumen into the blood stream requires secondary active transport. Which type of work is required?

transport work