560 A, B, D Flashcards
Copper deficiency can lead to reduced activity of dopamine beta-monooxygenase (DBM), which converts dopamine -> norepinephrine. Hence, in copper deficiency you can find elevated urinary ____(a)____ and reduced urinary ____(b)_____ .
- ) (a) VMA, (b) HVA
- ) (a) HVA, (b) 5HIAA
- ) (a) 5HIAA, (b) VMA
- ) (a) HVA, (b) VMA
4.) (a) HVA, (b) VMA
Match the pathways of alcohol degradation with the appropriate enzyme.
- ) ethanol + NAD+ -> acetaldehyde + NADH
- ) acetaldehyde + NAD+ -> acetate + NADH
- ) ethanol + NADPH -> acetaldehyde + NADP+
alcohol dehydrogenase
cytochrome P450 CYP2E1
aldehyde dehydrogenase
1.) ethanol + NAD+ -> acetaldehyde + NADH
uses alcohol dehydrogenase
- ) acetaldehyde + NAD+ -> acetate + NADH uses aldehyde dehydrogenase
- ) ethanol + NADPH -> acetaldehyde + NADP+ uses cytochrome P450 CYP2E1
Homogentisate (HGA) may be elevated in urine from excess supplementation of the amino acid ______________.
- ) Cysteine
- ) Methionine
- ) Tyrosine
- ) Tryptophan
3.) Tyrosine
The inner membrane of the mitochondria is a folded up throughout the organelle because
It results in a greater surface area for ATP synthesis
Select the correct answer:
A. Fructose absorption is not energy requiring.
B. Fructose-6-P is the major fuel source for the liver.
C. Affinity of glucokinase is 20 times greater for glucose than for fructose
D. Fructose is converted into galactose in order to enter glycolysis.
C. Affinity of glucokinase is 20 times greater for glucose than for fructose
Proteases catalyze ______.
Hydrolysis
Match
Hydroxyl Radical Intracellular water: Glutathione reduced: Glutathione oxidized: Electron transport chain:
Fenton reaction Disulfide bond Internal cellular respiration Antioxidant High energy radiation damage
Hydroxyl Radical: Fenton reaction
Intracellular water: high energy radiation damage
Glutathione reduced: Antioxidant
Glutathione oxidized: disulfide bond
Electron transport chain: Internal cellular respiration
What happens during beta oxidation? Hint fatty acids
Fatty acids are converted into acetyl CoA
In _______ inhibition, the inhibitor binds only to the ES (substrate) complex.
Noncompetitive
Select the INCORRECT statement about the regulation of carbohydrate metabolism:
A. High insulin levels favors high glucose production from gluconeogenesis or from gylcogen breakdown.
B. Pyruvate dehydrogenase is deactivated by high ATP levels.
C. Glucokinase and pyruvate kinanse are the two enzymes that drive glycolysis and are activated by insulin.
D. Oxaloacetate can not cross the mitochondrial membrane.
A. High insulin levels favors high glucose production from gluconeogenesis or from gylcogen breakdown.
Carbonic anhydrase require what metal ion?
Zinc
Which enzyme does ATP inhibit? Hint p
Phosphofructokinase
The tertiary structure of a protein: A. Is composed of many secondary units B. Is a sequence of amino acids C. Polypeptide chains assembled into multisubunit structures D. Do not contain a helix and B sheets
A. Is composed of many secondary units
Regarding enzymes:
A. the activity of the enzyme can be affected by what’s associated with its domains
B. lyases catalyze the formation of bonds, such as C-O and C-S, accompanied by the use of ATP
C. enzymes alter the equilibrium of a reaction
D. allosteric enzymes show a hyperbolic-shape curve
E. all of the above are true
A. the activity of the enzyme can be affected by what’s associated with its domains
Myoglobin shows which kind of structure? A. Primary B. Secondary C. Tertiary D. Quaternary
C. Tertiary
True/False: protein phosphatases can remove phosphate groups from enzymes.
True
True/False: Internal respiration centers on the fact that oxygen is the final electron acceptor in the electron transport system.
True
True/False: The electron transport system is located within the mitochondrial matrix.
False; it is found in the inner mitochondrial membrane
Fructose 2,6-bisphosphate strongly stimulates phosphofructokinase and inhibits fructose 1,6-bisphosphatase. Hence, _____ is accelerated and _____ is diminished in the fed state.
Glycolysis, gluconeogenesis
True/false: The covalent regulation of both glycogen synthase and glycogen phosphorylase depends upon their respective states of phosphorylation.
True
Which pathway does ATP inhibit?
Glycolysis
Which enzyme does ADP activate? Which enzyme does ADP activate?
Phosphofructokinase
What does HMP stand for (1) and what are its other names (2)? What is its purpose (3)? Does it lead to the formation of ATP? If not, what is its function (4)?
1) Hexose-monophosphate pathway
2) Pentose phosphate pathway
3) Alternative route for the metabolism of glucose
4) Formation of NADPH for synthesis of fatty acids and steroids, and the formation of ribose-5-phosphate for nucleotide and nucleic acid formation
What is TPP? Which pathways is it involved in?
1) Thiamine Pyrophosphate
2) Citric Acid Cycle and Pentose Phosphate Pathway
_____ is an important cofactor that acts catalytically in the decarboxylation of α-keto acids and the transketolase reaction.In the mechanism of TPP-dependent enzymes, the cofactor is a carrier of _________ residues
1) Thiamine Pyrophosphate (TPP)
2) Hydroxyalkyl residues
What two pathways is Biotin involved in?
Fatty acid synthesis and gluconeogenesis
An _____ inhibitor dissociates very slowly from its target enzyme because it has become tightly bound to the enzyme either covalently or non-covalently. Examples?
1) Irreversible
2) Penicillin, aspirin
A _____ inhibitor diminishes the rate of catalysis by reducing the proportion of enzyme molecules bound to a substrate.
Competitive
In _______ inhibition, the inhibitor binds only to the ES (substrate) complex.
Noncompetitive
In the presence of a competitive inhibitor, an enzyme will have ______ Vmax.
Greater
Same
Smaller
The same
In the presence of an uncompetitive inhibitor, the Vmax will ________. What happens to the Km?
Same
Higher
Lower
Reduced
1) Be lower
2) Km is reduced
What converts oxidized glutathione (GSSH) to the reduced form (GSH), and which enzyme catalyzes this conversion?
NADPH, glutathione reductase
What is the most common cause of metabolic acidosis?
What is the most common cause of metabolic acidosis?
What marker indicates Cushing’s disease, and what is it caused by?
Excessive cortisol levels, caused by external forces such as glucocorticoid therapy or internal forces such as a tumor producing adrenocorticotropic hormone (ACTH) causing excess cortisol production
What markers indicate Addison’s disease, and what is it caused by?
Low levels of cortisol and aldosterone, caused by an autoimmune disease that damages the adrenal gland
What are symptoms of Addison’s disease?
Weight loss, low blood pressure, hypoglycemia, fatigue, and skin hyperpigmentation
What is arachidonic acid
A polyunsaturated omega-6 fatty acid that is responsible for muscle tissue inflammation
Arachidonic acid leads to an increase in the production of _____ that help raise immunity and inflammatory responses in your body.
Eicosanoids
_________ are the precursors of red blood cells, platelets, granulocytes (polymorphonuclear leukocytes [PMNs]: neutrophils, eosinophils, and basophils), monocyte-macrophages, dendritic cells (DCs), and mast cells and osteoclasts. They compose a critical arm of the immune system, largely responsible for ______ defense against an array of pathogens.
Myeloid progenitor cells, innate
________ are responsible for the production of immunity mediated by cells or antibodies and including lymphocytes, lymphoblasts, and plasma cells. They originate from the _______, reach the ______, and mature into functional ______.
T cells
Bone marrow
Lymphoid cells
Thymus
Lymphoid cells, bone marrow, thymus, T cells
What is pathogenesis?
The origin and development of a disease; the mechanism whereby something causes a disease
What is myalgia?
Pain in a muscle or group of muscles
What is arthralgia?
Inflammation and pain from within the joint itself
How are prostaglandins generated, and what blocks their biosynthesis?
From arachidonic acid by the action of cyclooxygenase (COX) isoenzymes; blocked by NSAIDs
For which body systems do prostaglandins help maintain normal function?
Cardiovascular, pulmonary, renal, gastrointestinal
Which inflammatory mediator does heparin generate, and via activation of what from the blood coagulation system?
Bradykinin; factor XII
By regulating the mediators in mast cells, ______ may influence the expression of inflammatory and immunological responses.
Heparin
What are the major inflammatory mediators? (3)
Histamine Cytokines Heparin Leukocytes Prostaglandins
Heparin, histamine, prostaglandins
What does prostaglandin production depend on? (“The activity of…)
The activity of prostaglandin G/H synthases (COX-1 and COX-2)
_______, expressed constitutively in most cells, is the dominant source of ______ that serve housekeeping functions, such as gastric epithelial cytoprotection and homeostasis. ______, induced by inflammatory stimuli, hormones and growth factors, is the more important source of ________ formation in inflammation and in proliferative diseases, such as cancer.
Cox-2
Prosanoids
Prostanoid
Cox-1
COX-1, prostanoids, COX-2, prostanoid
How to allergens and antibodies interact?
If you have an allergy, your immune system overreacts to an allergen by producing antibodies called Immunoglobulin E (IgE). These antibodies travel to cells that release chemicals, causing an allergic reaction
A(n) \_\_\_\_\_\_\_\_\_\_ hemorrhage occurs when escaping blood accumulates between the outer-most layer of the meninges and the cranial bones. A. epidural B. subarachnoid C. subdural D. supraarachnoid E. epipial
A. epidural
Which term describes the changing of a cell to a more resistant type? A. dysplasia B. hyperplasia C. metaplasia D. hypertrophy E. apoptosis
C. metaplasia
What phagocytic white blood cells respond first in inflammatory response to bacteria? A. Macrophages B. Eosinophils C. Neutrophils D. Lymphocytes E. Monocytes
C. Neutrophils
What powerful vasoconstrictor raises the blood pressure by causing the peripheral arterioles to constrict? A. Renin B. Angiotensin I C. Angiotensin II D. Angiotensin-converting enzyme E. Aldosterone
C. Angiotensin II
All of the following may be associated with hepatic cirrhosis, EXCEPT:
A. portal hypertension.
B. esophageal varices.
C. hepatic encephalopathy.
D. increased arterial and venous blood flow through the liver.
E. ascites.
D. increased arterial and venous blood flow through the liver.
Cells that most commonly active during chronic infections are:
A. Lymphocytes, monocytes, and plasma cells
B. Polymorphonuclear leukocytes, monocytes, and mast cells
C. Complement and bradykinins
D. exudate, transudate, and pus
A. Lymphocytes, monocytes, and plasma cells
The most important cell in the acute inflammatory response is an actively phagocytic cell called the \_\_\_\_\_\_\_\_\_\_. A. mononuclear cell B. monocyte C. polymorphonuclear leukocyte D. macrophage E. erythrocyte
C. polymorphonuclear leukocyte
Which of the following is not a member of the cytokine family? A. interleukin B. tumor necrosis factor c. T lymphocyte d. Interferon
c. T lymphocyte
This is the first immunoglobulin formed in response to an invading antigen. (Ig ?)
IgM
\_\_\_\_\_\_\_\_ immunity is characterized by the formation of a population of lymphocytes that can attack and destroy the foreign material. A. Acquired B. Humoral C. Cell-mediated D. Hypersensitive E. Innate
C. Cell-mediated
\_\_\_\_\_\_\_\_\_ immunity is associated with the production of antibodies that can combine and eliminate the foreign material. A. T-cell mediated B. Humoral C. Cell-mediated D. Hypersensitive E. Passive
B. Humoral
John Jones was exposed to a person who was ill with an infectious disease, and John received an injection of globulin to provide protection against the infectious agent to which he was exposed. What is the class of antibody in the gamma globulin that provides the protection? A. IgG B. IgA C. IgM D. IgD E. IgE
A. IgG
One method the body uses to destroy bacteria is by forming a membrane attack complex that produces perforations in the walls of bacterial cells and enveloped viruses, thereby causing their destruction. What is the substance producing the membrane attack complex?
A. Interferon
B. Lymphokines produced by T lymphocytes
C. Gamma globulin produced by B lymphocytes
D. Complement
E. Antibodies
D. Complement
\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_ inhibit the multiplication of viruses that have infected a cell. A) natural killer cells B) tumor necrosis factor C) interferons D) B lymphocytes E) T lymphocytes
C) interferons
An angioma is a
A. benign tumor projecting from an epithelial surface
B. malignant tumor of bone
C. malignant tumor arising from epithelial cells
D. benign blood vessel tumor
E. benign tumor of cartilage
D. benign blood vessel tumor
This is a neoplasm of bone marrow that causes weakness of bones. A. Hodgkin's lymphoma B. acute leukemia C. Wilm's tumor D. retinoblastoma E. multiple myeloma
E. multiple myeloma
A malignant tumor arising from glands within the lining of the uterus is a/an \_\_\_\_\_\_\_\_\_\_. A. adenocarcinoma B. myosarcoma C. myoma D. polyp E. angioma
A. adenocarcinoma
Which of these is a benign tumor of fat cells? A. Adenocarcinoma B. Lipoma C. Liposarcoma D. Lymphosarcoma E. Leukemia
B. Lipoma
T/F: Pitting edema most frequently occurs in left heart failure.
F
Which of the following conditions does not predispose to edema?
A. Heart failure
B. Von Willebrand’s factor deficiency
C. Increased capillary permeability
D. Low plasma osmotic pressure resulting from low blood proteins
E. Lymphatic obstruction
B. Von Willebrand’s factor deficiency
This substance is released into the blood during an acute inflammatory event. A. homocysteine B. folic acid C. LDL D. CRP E. heparin
D. CRP
Which of the following is not a frequent complication of a myocardial infarction? A. heart failure B. arrhythmias C. formation of mural thrombi D. rupture of the heart E. mitral valve prolapse
E. mitral valve prolapse
Antidiuretic hormone (ADH) is released in response to: A. Decreased serum osmolality B. Increased serum osmolality C. Decreased urinary urea nitrogen D. Increased urinary urea nitrogen
B. Increased serum osmolality
Alpha-amino-N-butyric acid (AANB) may be elevated in alcoholism. What nutrient may be deficient when AANB is elevated?
- ) B2
- ) B6
- ) Iron
- ) B3
B6
Biomethylation to remove arsenic requires the use of ____ SAMe as a methyl donor.
- ) 2
- ) 1
- ) 3
- ) 4
1.) 2
Taurine, which is utilized in skeletal muscle and bile, can be created from cysteine with the assistance of what nutrients?
- ) Iron, NAD, FAD, B12
- ) Iron, P5P, Folate, B12
- ) Iron, NAD, FAD, Folate
- ) Iron, P5P, FAD, NAD
4.) Iron, P5P, FAD, NAD
Amino acid conjugation requires two steps. The first step is activation of the xenobiotic carboxylic acid using the enzyme (a)________, which requires ATP and (b) ____________.
- ) (a) acyl synthetase, (b) B5
- ) (a) transacetylase, (b) B5
- ) (a) acyl synthetase, (b) P5P
- ) (a) transacetylase, (b) P5P
1.) (a) acyl synthetase, (b) B5
Mutations in the SN1-SN2 transporter can lead to elevations in what 3 AA?
- ) Gln, Asn, His
- ) Glu, Asn, His
- ) Glu, Asp, His
- ) Gln, Asp, His
4.) Gln, Asp, His
What enzyme requiring B6 converts Glutamate -> Gamma-amino-N-butyric acid (GABA)?
- ) Succinate semialdehyde dehydrogenase
- ) Glutamic acid decarboxylase (GAD)
- ) Monoamine oxidase
- ) Catechol-O-methyltransferase
2.) Glutamic acid decarboxylase (GAD)
The pathway Arg -> Orn + a-KG -> -> Pro for the creation of collagen via the enzymes arginase, ornithine aminotransferase and pyrroline-5-carbosylate reductase require what nutrients for proper activity?
- ) Mn++, B5, retinoic acid, B3, Mg++
- ) Mn++, P5P, B5, B3, Mg++
- ) Zn++, B5, retinoic acid, B3, Mg++
- ) Mn++, P5P, retinoic acid, B3, Mg++
4.) Mn++, P5P, retinoic acid, B3, Mg++
Elevations in lactate can indicate disruption of carbohydrate metabolism and the body’s need to regenerate the vitamin _____________ to keep the glycolytic pathway functional
- ) NADH
- ) NADPH
- ) FADH
- ) NAD
4.) NAD
There are two major types of sulfotransferases. One type is membrane-bound in the golgi apparatus and sulfates GAGs and glycoproteins, while the other is located in the __________ and conjugates steroids, catecholamines, T4, bile acids, and xenobiotics.
- ) cytosol
- ) nucleus
- ) smooth ER
- ) mitochondria
1.) cytosol
GS (Glutamine Synthetase) requires the use of what minerals to assist in the conversion of Glu -> Gln?
- ) Mg++, Se++
- ) Se++, Mn++
- ) Mg++, Zn++
- ) Mg++, Mn++
4.) Mg++, Mn++
What AA is a precursor to serine and component of glutathione?
- ) Tryptophan
- ) Glycine
- ) Phenylalanine
- ) Taurine
2.) Glycine
Catechol-O-methyltransferase (COMT) utilizes _________ and _________ to degrade the catecholamines dopamine, norepinephrine, and epinephrine.
- ) Cu++ and Fe++
- ) NAD and Mg++
- ) NAD and P5P
- ) SAMe and Mg++
4.) SAMe and Mg++
Citrate, Cis-Aconitate, and Isocitrate are located at the beginning of the TCA cycle. Elevations in cis-aconitate can indicate dysfunction of the enzyme aconitase, which requires the mineral ______________ and cysteine.
- ) Se++
- ) Zn++
- ) Cu++
- ) Fe++
4.) Fe++
The enzyme CPOX (coproporphyrinogen oxidase) converts coproporphyrinogen III to protoporphyrinogen IX and is blocked by the heavy metals.
- ) Lead and Mercury
- ) Mercury and Arsenic
- ) Arsenic and Cadmium
- ) Lead and Cadmium
1.) Lead and Mercury
Formiminotransferase utilizes ____________ to convert FIGLU to glutamate.
- ) 5,10-methylene THF
- ) 5-formimino-THF
- ) THF
- ) 5MTHF
3.) THF
Match the appropriate detox function with the specific nutrient:
- ) toxic metal binding & antioxidant protection
- ) hepatic conjugation substrates
- ) glutathione regeneration
- ) methyl donors
- ) lead protection
- ) stimulate Phase I and Phase II detox
vitamin C Calcium glycine, sulfate Cruciferous Met, SAMe NAC, Se, Mn, Cu, Zn
- ) vitamin C
- ) glycine, sulfate
- ) NAC, Se, Mn, Cu, Zn
- ) Met, SAMe
- ) Calcium
- ) Cruciferous
Elevations in Cortisol have been implicated in insulin resistance. Which of the following is NOT an action of high cortisol levels?
- ) Increased FA synthesis
- ) Increased gluconeogenesis
- ) Upregulation of GLUT4 receptors
- ) Increased glycogenolysis
3.) Upregulation of GLUT4 receptors
Alcohol can deplete numerous nutrients. Match the nutrient depletion and the type of symptom/problem that can occur when that nutrient is depleted.
- ) Depletion of vitamins B1 and B6 causes
- ) Depletion of vitamins B6 and B9 causes
- ) Depletion of vitamin B1 causes
- ) Depletion of vitamin D causes
Osteoporosis, neurological symptoms, Wernicke-Korsakoff syndrome, hematological symptoms
- ) neurological symptoms
- ) hematological symptoms
- ) Wernicke-Korsakoff syndrome
- ) osteoporosis
Precoproporphyrin may elevate when __________ blocks the last step of UROD, leading to the accumulation of pentacarboxyporphyrinogen, which gets converted by CPOX to precoproporphyrin.
- ) Mercury
- ) Lead
- ) Arsenic
- ) Cadmium
1.) Mercury
Conversion of norepinephrine -> epinephrine via the enzyme Phenylethanolamine-N-Methyltransferase (PNMT) utilizes what nutrient in this reaction?
- ) Copper
- ) Iron
- ) SAMe
- ) Vitamin C
3.) SAMe
UROD is blocked by both ___(a)___ . The difference between the two heavy metals is that ___(b)___ causes high pentacarboxyporphyrin because it slows UROD down, making the last decarboxylation step difficult.
- ) (a) As and Hg, (b) Hg
- ) (a) As and Hg, (b) As
- ) (a) Hg and Pb, (b) Pb
- ) (a) Pb and As, (b) As
1.) (a) As and Hg, (b) Hg
If there is a defect in the SN1-SN2 transporter allowing Gln into the presynaptic nerve terminal, what will happen to Glu levels within the presynaptic nerve terminal?
1.) Glu levels will decline unless the EEAC1 receptor can compensate
- ) Glu levels will increase unless the EEAC1 receptor can compenate
- ) Glu levels will increase unless the GLAST receptor can uptake Glu into the perineuronal astrocyte
- ) Glu levels will decline unless the GLAST receptor can uptake Glu into the perineuronal astrocyte
1.) Glu levels will decline unless the EEAC1 receptor can compensate
GSH can conjugate with electrophiles through the enzyme ___________ to reduce the reactivity of these harmful substances.
- ) glutathione-S-transferase (GST)
- ) glutamyl-transferase
- ) cysteinyl-glycinase
- ) acetylase
1.) glutathione-S-transferase (GST)
High ammonia levels from urea cycle dysfunction can lead to the accumulation of _ (a) . Treatment with (b) , may help the urea cycle function better and decrease urinary (a) levels.
- ) (a) Orotate, (b) Arginine, Mg++
- ) (a) Pyroglutamate, (b) NAC
- ) (a) Glucarate, (b) Arginine, Mn++
- ) (a) Sulfate, (b) NAC
1.) (a) Orotate, (b) Arginine, Mg++
The Bohr effect explains that a decrease in the amount of oxygen associated with hemoglobin (Hb) due to a reduced affinity of oxygen for Hb is the result of:
- ) Increased pC02 and increased pH
- ) Increased pCO2 and decreased pH
- ) Decreased pC02 and decreased pH
- ) Decreased pC02 and increased pH
2.) Increased pCO2 and decreased pH
Homogentisate (HGA) may be elevated in urine from excess supplementation of the amino acid ______________.
- ) Cysteine
- ) Methionine
- ) Tyrosine
- ) Tryptophan
3.) Tyrosine
High levels of suberate, adipate and ethylmalonate can be reduced with vitamin ________, which is utilized by the flavoprotein enzyme Fatty Aycl-CoA Dehydrogenase.
B1 2 3 5 ?
B2
Lysine does NOT undergo the initial transamination requiring B6 but downstream conversion of alpha-aminoadipic acid (a-AAA) to alpha-ketoadipate does require B6. What nutrient is required for the initial conversion of Lys -> Saccharopine?
- ) B2
- ) B12
- ) B5
- ) B3
4.) B3
What are the four conditionally essential amino acids?
- ) Arg, Gln, Gly, Ser
- ) Arg, Glu, Gly, Tau
- ) Arg, Glu, Gly, Ser
- ) Arg, Gln, Gly, Tau
4.) Arg, Gln, Gly, Tau
BCAA are converted to alpha-ketoacids via BCAA transaminase. This enzyme requires the cofactor:
- ) B3
- ) B6
- ) B5
- ) B2
2.) B6
In this equation of Bronsted-Lowrey (B-L) acid/base formula, select the TRUE answer:NH3 + H2O = NH+4 + OH-
A. NH3 is the B-L conjugated base, and H20 is the B-L acid.
B. NH+4 is the B-L conjugated acid, and Oh- is the B-L conjugated base.
C. Nh3 is the B-L acid, and Oh- is the B-L base
D. Nh+4 is the B-L acid and Oh- is the B-L base
B. NH+4 is the B-L conjugated acid, and Oh- is the B-L conjugated base.
The hemoglobin molecule is ____ easily saturated with oxygen than is myoglobin, at a given partial pressure of oxygen.
A. More
B. Less
B. Less.
T/F: Myoglobin binding includes positive cooperativity.
F
T/F: Interplay with the bicarbonate buffer occurs with myoglobin but not with hemoglobin.
False.
Which is true about replication:
A. Topoisomerase unwinds the DNA
B. Primases lay down primers on the leading strand
C. The leading strand is synthesized in a continuous fashion and the lagging strand is not
D. There is only one point of replication initiation in eukaryotes
C. The leading strand is synthesized in a continuous fashion and the lagging strand is not
Catalysts that change the rate of reactions are what category of physiological proteins?
a. hormones
b. enzymes, which don’t alter the equilibrium
c. enzymes, which alter the equilibrium
d. transport proteins
b. enzymes, which don’t alter the equilibrium
Regarding enzymes:
A. a whole metabolic pathway can be controlled by controlling the activity of a key enzyme that is involved in that pathway
B. a transition state is one where the enzyme is complexed to a very high-energy level, relatively unstable intermediate
C. for thermal effects upon enzymes, a bell shaped curve would be expected
D. all of the above are true
D. all of the above are true
True/False: The electron transport system is located within the mitochondrial matrix.
False; it is found in the inner mitochondrial membrane
The endoplasmic reticulum (ER) consists of membranes w/ smooth & rough components involved in all of the following EXCEPT:
a. formation of lysosomes & peroxisomes
b. membrane synthesis
c. protein & lipid synthesis
d. protein folding
e. cellular respiration
f. detoxification reactions
g. Ca2+ signaling
h. contains cytochrome P450
e. cellular respiration
T/F: A closed system can exchange both energy and matter with its surroundings.
False
T/F: An open system can exchange only energy with its surroundings, not matter.
False.
Lewis definition of acids and bases (hint pair? Electron?)
a Lewis acid is an electron pair acceptor, while a base is an electron pair donor.
DNA is all of the following EXCEPT:
a. repository of genetic information in the nucleus which passes on the genetic information from one generation to the next.
b. In humans exists as a double-stranded helix.
c. is a polymer deoxyribonucleoside monophosphates covalently linked by 3’-> 5’ - phosphodiester bonds.
d. contain the bases adenine, cytosine, uracil, and guanine.
d. contain the bases adenine, cytosine, uracil, and guanine.
T/F: RNA (ribonucleic acid) is double-stranded with a backbone made of alternating sugar (ribose) and phosphate groups.
F
[T/F] A large KM value indicates high affinity binding of enzyme to substrate.
F
Which of the following is false regarding enzyme inhibition?
a. an inhibitor diminishes the velocity of an enzyme-catalyzed reaction.
b. competitive inhibition occurs when inhibitor binds reversibly to the same site that the substrate would normally occupy.
c. non-competitive inhibition occurs when the inhibitor and substrate bind at different sites on the enzyme.
d. Irreversible inhibitors bind to enzymes through non-covalent bonds.
d. Irreversible inhibitors bind to enzymes through non-covalent bonds.
Which of the following is TRUE.
a. enzyme cofactors and coenzymes are molecules required to activate enzymes.
b. cofactors are organic molecules such as vitamins.
c. coenzymes are inorganic ions, usually positively charged metal atoms like Zn, Mg, Fe.
d. All of the above are true.
a. enzyme cofactors and coenzymes are molecules required to activate enzymes.
Glyosidic bonds:
a. link sugars by glycosyltransferases
b. Most glucose units in glycogen are lined by α-1, 4-glycosidic
bonds, with branches formed by α-1, 6-glycosidic bonds every
10 glucose units.
c. When two OH groups that are involved in
forming a glycosidic bond are pointing down, they will form an α-bond
d. All of the above are true.
d. All of the above are true.
T/F: Steroids are a class of organic compounds with four rings organized in a specific conformation. All steroids contain this cyclopentanoperhydrophenanthrene skeleton.
T
T/F Triacylglycerols (TAGs) sometimes called triglycerides consist of one fatty acid linked to three glycerol molecules by ester bonds
F
Which is FALSE:
a. LDL delivers cholesterol to the peripheral tissues that require cholesterol for membrane formation or steroid hormone synthesis.
b. HDL is rich in cholesterol but poor in triacylglycerol, carries cholesterol from the periphery to the liver where it is excreted in bile as cholesterol or after conversion to bile salts.
c. VLDL and chylomicrons transport triacylglycerols to be used for energy (e.g. muscle) or stored (e.g. fat cells).
d. lipid transfer proteins facilitate the shuttling of phospholipids and other fatty acid groups within cell membranes
d. lipid transfer proteins facilitate the shuttling of phospholipids and other fatty acid groups between cell membranes
NADPH is needed for all except:
a. Fatty acid biosynthesis
b. Cholesterol biosynthesis
c. Neurotransmitter biosynthesis
d. Nucleotide biosynthesis
e. Reduces oxidized glutathione
f. Cytochrome P450 monooxygenase
g. All of the above
G
T/F: The PPP consumes some ATP.
F
T/F: Glycerol enters glycolysis and/or gluconeogenesis as glyceraldehyde 3-phosphate
T
What are symptoms of Cushing’s disease?
Weight gain (especially in the trunk), high blood pressure, “moon face,” hyperglycemia, a fat pad on the back referred to as a “buffalo hump”
T/F: Prostaglandins are stored, not synthesized as needed, and are slowly metabolized.
F
Where is histamine stored, and what stimulates its release?
Stored in the granules of mast cells, basophils, platelets; acute inflammation, anaphylatoxins, and histamine releasing factors
_____ immunity refers to nonspecific defense mechanisms that come into play immediately or within hours of an antigen’s appearance in the body, activated by chemical properties of the antigen. ______ immunity refers to antigen-specific immune response, created in response to exposure to a foreign substance.
Innate, Adaptive
\_\_\_\_\_\_\_\_\_\_ are antibodies produced by plasma cells. A. Immune-response genes B. Interleukins C. Interferons D. Immunoglobulins E. Complements
D. Immunoglobulins
T/F: Plasma cells make antibodies.
True
Injury and infection by a pathogenic organism can cause inflammation. What else can cause an inflammatory response?
A. Administration of corticosteroid hormones
B. Excess lysosomes in the cells
C. Interaction of antibodies and antigens
D. No other causes exist
E. Use of NSAIDs
C. Interaction of antibodies and antigens
Cytokines that send regulatory signals between cells of the immune system are \_\_\_\_\_\_\_\_\_\_. A. interferon B. interleukins C. monokines D. tumor necrosis factors E. immunoglobulins
B. interleukins
Which type of hypersensitivity reaction causes tissue injury by the formation of immune complexes? A. Type I B. Type II C. Type III D. Type IV
C. Type III
Digitalis (digoxin) is often used to treat which condition? A. atrial fibrillation B. complete heart block C. rheumatic fever D. mitral regurgitation E. ventricular fibrillation
A. atrial fibrillation
