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