Dr.Lewis Integrated Science Exam 3 2017

Pyruvate is converted into this compound that enters the TCA cycle

AcetylCoA

The enzyme responsible for degrading glycogen in glycogenolysis is

Glycogen phosphorylase

When a lipid molecule is hydrolyzed, this bond is broken which splits the molecule into its component parts:

Ester

Which of the following is NOT a pancreatic enzyme used for the digestion of proteins?

A. Aminopeptidase

B. Trypsin

C. Chymotrypsin

D. Cholesteryl ester hydrolase

D. Cholesteryl ester hydrolase

If the body has all of the glucose it needs, any extra glucose taken in will probably undergo

Glycogenesis **

How many molecules of pyruvate are produced from the metabolism of 1 molecule of glucose during glycolysis?

2

The following hormone causes the release of glucose from glycogen reserves when a hypoglycemic condition develops:

Glucagon

The following hormone removes excess glucose from the bloodstream

Insulin

When a lipid molecule is hydrolyzed these products are generated

Glycerol and Fatty acids

Fatty acids are broken down by this metabolic process

Beta oxidation

Which of the following is NOT a steroid hormone?

A. Testosterone

B. Hydroxybuterone

C. Estradiol

D. Progesterone

E. Aldosterone

B. Hydroxybuterone

The number of ATPs produced by the complete combustion of glucose to carbon dioxide and water:

38

Plasma lipoproteins include all of the following EXCEPT:

A.LDL

B. Chylomicrons

C. VDL

D. VLDL

E. HDL

C. VDL

Which of the following enzymes is NOT found in the EMP pathway?

A. Hexokinase

B. Phosphofructokinase

C. Enolase

D. Fumarase

E. Aldolase

D. Fumarase

When high emand exercising muscle generates anaerobic conditions, this metabolic pathway is induced to convert lactate to glucose in the liver.

Cori cycle

Which of the following is responsible for mediating allergic reactions?

Histamine

A function of serotonin is:

To regulate sleep

What is the diagnostic value of Alt & AST?

ALT & AST is elevated in liver disease

Which of these is NOT a catecholamine?

A. Norepinephrine

B. Dopamine

C. Serotonin

D. Epinephrine

Serotonin

Which is a source from which amino acids are supplied to the body?

A. By the degredation of body proteins

B. Consumption of dietary proteins

C. Synthesis of nonessential amino acids from simple intermediates of metabolisms

D. all of the above

All of the above

Which of the following is NOT an intermediate in the urea cycle?

A. Orinithine

B. Argininosuccinate

C. Arginine

D. citrulline

E. Lysine

E. lysine

PKU is the most common clinically encountered inborn error of amino acid break down of which amino acid?

Phenylalanine

The initial digestion of proteins begins in the:

Mouth ***

Which of the following enzymes are activated by the presence of HCl?

Pepsin

During amino acid catabolism, what enzyme transfers an amino group from glutamate to oxaloacetate and form aspartate?

AST

What does AST stand for?

Aspartate amino transferase

The primary transporter of fructose into cells is:

GLUT-5

Oxaloacetate is generated from the dehydrogenation of this molecule:

L-Malate

The enzyme that produces glyceraldehyde 3-P and dihydroxyacetone-P from fructose:

Aldose

The product of the enzyme hexokinase in glycolysis is:

Glucose 6-P

Enolase converts this substrate to phosphoenolpyruvate (PEP)

2-phosphoglycerate

The following enzyme converts glyceraldehyde 3-P to 1,3 bisphosphoglycerate:

Glyceraldehyde 3-P dehydrogenase

The enzyme that converts DHAP to glyceraldehyde 3-P:

Phosphotriose isomerase

Esters pf fatty acids and high molecular weight alcohols are known as:

Steroids

Epinephrine and norepinephrine are synthesized from

Tyrosine

GABA is synthesized from the amino acid

GLutamate

The amino acid tryptophan is used to synthesize this neurotransmitter

serotonin

which of the following converts trypsinogen to trypsin?

Enterokinase

Lesch-Nyhan syndrome is a defect in which of the following?

Purine salvage pathways

Zymogens are inactive forms of

Enzymes

Which of the following is known as the debranching enzyme?

Amylo-alpha (1-6) glucosidase

Which of the following complexes is known as NADH dehydrogenase?

Complex 1

This molecule is used as a diagnostic test for chronic hyperglycemia

HbAlc

This lipoprotein is known as the "good" cholesterol

LDL

These hormone-like substances play a role in inflammation

Prostaglandins

Gangliosides play a predominant role in these tissues

Brain

Oxidative phosphorylation occurs in the

Kreb cycle

Gout results from elevated levels of

Uric acid

Histamine is formed through the __________ of histidine

Decarboxylation

These cells are responsible for producing gastric HCL during protein digestion

Chief

General Knowledge of Carbohydrates

The alpha and beta forms of sugars, such as those observes for D-glucopyranose, are called

Anomers

Many oxidizing agents, such as Tollen's reagent, can be used to identify the presence of _______ sugars

reducing

Enzymes that transfer phosphate groups from ATP to another substance are called____.

kinases

Carbohydrates play critical roles in:

a. energy storage

b. components of membranes, dna, rna and proteins

c. structural functions

(a. b. and c. are correct)

The formula for a monosaccharise is _________, where n is typically a value of 3 to 7.

(CH2O)n

Two important trioses found in nature are:

glyceraldehyde and dihydroxyacetone

The most naturally abundant aldohexoses are:

glucose, mannose and galactose

in the naturally occurring D series of ketoses, the carbonyl is found on carbon number _____.

two

The disaccharide sucrose is composed of:

glucose and fructose

Carbohydrates can be linked to amino acids to form glycoproteins via an:

a. O-glycosidic bond to the serine hydroxyl group

b. O-glycosidic bond to the threonine hydroxyl group

c. N-glycosidic bond to the amide side chain in histidine

(all three are correct)

Functions of the carbohydrates on glycoproteins include:

a, cell surface identification markers

b. viral growth

c. protein turnover

(all three are correct)

What would be the molecular formula for a polymer made by linking 8 glucose molecules together by dehydration synthesis?

C46H96O48

Two monosaccharides combine to form disaccharides or polysaccharides. this involves the OH group of one monosacc. forming an ester linkage with the anomeric carbon of the second monosacc. this type of bond is called:;

O-glycosidic bond

The end product of glycolysis are

2 pyruvates, 2 ATP and 2 NADH

The activity of the glycolytic enzyme, phosphofructokinase, is subject to regulation. which statement given below about its regulation is true?

Three possible fates for pyruvate conversion to

Effect of lactate on glucogenesis

increases **

The correct sequence of enzymes responsible for the conversion of fructose-1,6-bisphosphate to phosphoenolpyruvate are

Aldolase, triose phosphate, G3P dehydrogenase, Phosphoglycerate kinase, phosphoglycerate mutase, enolase

The net ATPs made in glycolysis is __ and the total bymber of NADH made in glycolysis is___.

Two, Two

This enzyme catalyzes the formation of NADH in glycolysis

Glyceraldehyde phosphate dehydrogenase

Glyceraldehyde possesses a chiral center, thus it can exist in two stereoisomers known as:

Enantiomers

Another name for Beta-galactosidase is

lactase

In the naturally occurring D series of ketoses, the carbonyl is found on carbon number

2

Sucrose=

glucose and fructose

Maltose=

Two glucose units

Reducing sugars can reduce metal ions in solution. which of these sugars are reducing sugars?

Those with a free aldehyde group

Sugars have chiral centers. how many stereoisomers are there for a sugar with 3 chiral centers?

8? **

If the OH is drawn below the plane, it is in the ____ configuration. if the OH is above the plane, it is in the ____ configuration. these two configurations interconvert. this process is called ______.

Alpha; Beta; Anomerism

From the Integrated Resource Thingy

Which products of the citric acid cycle are directly or indirectly sources of energy?

GTP, NADH,FADH2

Which enzymes in the citric acid cycle are carefully regulated?

Citrate synthase, isocitrate dehydrogenase, alpha-ketoglutarate dehydrogenase

The approximate yield of ATP from complete oxidation of glucose is:

36 ATP if the glycerol-3-phosphate shuttle is used

38 ATP if the malate-aspartate shuttle is used.

Place the following reaction intermediates of the citric acid cycle in chronological order as they appear in the cycle:

I. malate

ii. fumarate

iii. succinyl CoA

iv. Citrate

v. Alpha-ketoglutarate

E. iv,v,iii,ii,i

Oxaloacetate is the keto acid (carbon skeleton) used to synthesize which amino acid:

Asp

Pyruvate is the keto acid (carbon skeleton) used to synthesize which amino acid:

Ala

Complete this reaction:

pyruvate + CoASH + NAD+ -->

acetyl-CoA + NADH + H+ + CO2

Which steps occur in beta oxidation?

The acyl-CoA is shortened by two carbons, which are removed at the CoA end of the molecule.

Oxidation occurs at the B position.

Each round of B oxidation produces one each of

NADH, FADH2, Acetyl-CoA

What is the yield of ATP from a fatty acid containing 18 carbon atoms?

146

The net (major) products of glycolysis are

2 pyruvates, 2 ATP, 2 NADH

all of the following are essential amino acids except:

a. Ile

b. Leu

c. Met

d. Thr

e.Ala

E. Ala

What is the principle underlying concept of allosteric regulation?

A binding or catalytic event at one site influences the binding or catalytic event at another site.

Enzymes that form C-C and C-S bonds are called

Ligases

Enzymes that form double bonds by removal or addition of groups, or addition of groups to double bonds, are called

Lyases

The enzyme common to both beta oxidation and the electron transport chain is

Acyl CoA Dehydrogenase

During fatty acid synthesis, the intermediates are linked to

Acyl carrier protein (ACP-SH)

What molecules are critical to assimilation of ammonium in animal and plant cells?

Glutamate, glutamine, and carbamoyl phosphate

alpha-ketoglutarate required by the citric acid cycle can be replenished by the action of ____, using glutamate and NADP+.

Glutamate dehydrogenase

Dietary proteins are first degraded in the stomach by the action of the protease:

Pepsin