University of New England (UNE )

Which of the following is the major regulation point for transport of fatty acids into the mitochondria? correct answer: carnitine acyltransferase I The primary activation of triacylglycerol mobilization in adipocytes is through __________ of the enzyme ____________. correct answer: phosphorylation; hormone sensitive lipase Which of the following lipoproteins distributes dietary lipids? correct answer: chylomicron Which of the following statements regarding lipid digestion and absorp...

Which of the following is the major regulation point for transport of fatty acids into the mitochondria? correct answer: carnitine acyltransferase I The primary activation of triacylglycerol mobilization in adipocytes is through __________ of the enzyme ____________. correct answer: phosphorylation; hormone sensitive lipase Which of the following lipoproteins distributes dietary lipids? correct answer: chylomicron Which of the following statements regarding lipid digestion and absorp...

In the fasted state, fatty acyl-CoA are transported across the mitochondrial membrane. The transport of fatty acids via carnitine palmitoyl transferase I (CPTI) can be directly inhibited by which of the following compounds? a. Malonyl CoA b. Carnitine c. Acetyl CoA d. Palmitate correct answer: Malonyl CoA A 22-year-old woman engaging in a political protest goes on a hunger strike on a prominent corner in a city park. She refuses all offers of food except for water for the first 2 we...

Changes in the physiological variables listed below can alter the affinity of hemoglobin for oxygen. Which of the following will lower the affinity of hemoglobin for oxygen? correct answer: Increase in 2,3 bisphosphoglycerate (BPG) A decreased affinity will increase the rate of oxygen delivery to the tissues. This will occur when pH is low, there is an increase in CO2, protons or 2,3 BPG. The other scenarios (a, c, d) will all increase the affinity for O2. Which of the following proteins ...

Covalent catalysis is used by many enzymes to cleave peptide bonds. Which of the following amino acids would not facilitate this type of catalysis? (Think of the structure of the R-group of these amino acids) correct answer: Valine The R-group on valine does not have an active group to participate in covalent catalysis. This most commonly participating amino acids are cysteine, serine and histidine. Which of the following best describes the structure of heme? correct answer: A planar po...

Which of the following best describes tertiary structure? correct answer: Interactions between alpha helices and beta sheets to form a domain Movement of ammonia from an amino acid to an alpha-keto acid involves a family a enzymes best categorized as which of the following? correct answer: Transferases How do most enzymes reduce the activation energy needed to move a reaction forward? correct answer: Providing an active site most complementary the transition state Domains are common ...

What are the four different protein structures? correct answer: 1. Primary 2. Secondary 3. Tertiary 4. Quaternary What is the primary structure of a protein? correct answer: a linear sequence of amino acids in polypeptide chains which is written from the amino terminus (N-terminus) to the carboxyl terminus (C-terminus) What is the secondary structure made of? correct answer: a-helix, b-sheets, and bends, turns, or loops How are alpha helices formed? correct answer: They are forme...

During exercise the pathways of ____________________ and ______________________ are integrated as means of providing energy and reducing NH4+ levels. correct answer: BCAA catabolism and purine degradation The primary role of glutamine in the brain is to provide substrate for the synthesis of which of the following compounds? correct answer: neurotransmitters Alanine can be shuttled from the skeletal muscle to the liver where it is deaminated by which of the following enzymes? correct ans...

1. Pyruvate dehydrogenase kinase catalyzes a reaction that results in which of the following? correct answer: The phosphorylation and inactivation of E1 subunit (pyruvate dehydrogenase complex 1. Which of the following intermediates is an allosteric activator of pyruvate kinase? correct answer: a. Fructose 1.6 bisphosphate 1. Which of the following is the initial second messenger in the signaling cascade initiated by glucagon? correct answer: a. cAMP 1. Hereditary fructose intoleranc...

Which of the following lipoproteins is responsible for carrying cholesterol from peripheral tissues (i.e skeletal muscle) back to the liver? correct answer: HDL What is the primary role of LCAT (Lecithin-cholesterol acyltransferase)? correct answer: To esterify cholesterol transported by HDL Which enzyme is responsible for transferring triacylglycerol from VLDL to HDL in exchange for cholesterol? correct answer: LCAT (Lecithin-Cholesterol Acyltransferase) Which of the following lipop...

Carnitine palmitoyl transferase correct answer: - transfers acyl groups from CoA to carnitine & vice versa - inhibited by malonyl-CoA ketone bodies correct answer: - acetoacetate, β-hydroxybutyrate, acetone - oxidized as fuel source in extreme fasting d-3-hydroxybutyrate dehydrogenase correct answer: interconversion of acetoacetate and 3-hydroxybutyrate acetone correct answer: yielded by spontaneous decarboxylation of acetoacetate; waste product acetoacetate and 3-hydroxybutyr...

What enzyme is used by the gluconeogenic pathway but NOT in the glycolytic pathway? correct answer: Phosphoenolpyruvate Carboxykinase PEPCK Newborn screening results show a biotinidase deficiency in a 2 day old infant. The deficiency impairs the infant's ability to reuse and recycle biotin. Due to the enzymatic deficiency, the activity of what enzyme is likely impaired? correct answer: Pyruvate carboxylase If unregulated, which of the following pairs of enzymes would represent a futile ...

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Hemoglobin binds oxygen with a greater affinity in the: correct answer: R state Hemoglobin bound to heme is termed a holoprotein. The heme or porphoryin ring is required for oxygen binding and it is termed a: correct answer: prosthetic group Alpha helices and beta sheets are primarily stabilized by: correct answer: H bonding Ligases are a class of enzymes characterized by their ability to: correct answer: synthesize bonds between carbon atoms and an additional atom that is involved ...

Somatostatin reduces the secretion of both glucagon and insulin through which of the following mechanisms? a. Somatostatin activates an activator G-protein b. Somatostatin activates MAPK cascade c. Somatostatin activates an inhibitory G-protein d. Somatostatin uses Ca+2 as a downstream signal correct answer: c. Somatostatin activates an inhibitory G-protein Insulin mediated glucose uptake by muscle and adipose tissue is a result of which of the following mechanisms? a. Translocatio...

Control of Fatty Acid Synthesis vs. Oxidation correct answer: When Insulin is HIGH --> fatty acid synthesis occurs When Glucagon is HIGH --> lipolysis, fatty acid B-oxidation, ketogenesis occur **These never happen at the same time! Lipolysis correct answer: Process of releasing free fatty acids from triacylglycerols stored in the adipose IN THE FASTED STATE Steps of lipolysis correct answer: 1) Hormone Sensitive Lipase: activated by glucagon and epinephrine TAGs are hydroly...

Which applies to the manner in which carbon bonds in alkanes? correct answer: The bonds are formed with carbon using an sp3 configuration The alkanes represent one family of organic compounds... correct answer: that is composed of carbon and hydrogen Which of the following is an alcohol? correct answer: CH3CH2OH What is meant by the term "saturated" when describing hydrocarbons? correct answer: They are saturated with hydrogen and only have single binds between carbons Which of...

Bronsted-Lowry Acid correct answer: a substance that can transfer H+ Bronsted-Lowry Base correct answer: a substance that can accept H+ Strong Acid correct answer: an acid that dissociates completely in water to give H+ ions Strong Base correct answer: a base that dissociates completely in water to give OH- ions Weak Acid correct answer: an acid that dissociates incompletely in water Weak Base correct answer: a base that dissociates incompletely in water Conjugate Acid co...

what is a major difference between organic and inorganic compounds? correct answer: organic contain carbon what is the reason why there are so many organic compounds? correct answer: carbon atoms can form stable covalent bonds with other carbon atoms the vast number of organic compounds is due to the unique chemistry of carbon. this chemistry involves correct answer: formation of long chains& isomerism Which applies to the manner in which carbon bonds in alkanes? correct answer: the...

Which of the following formulas represents butane? CH3CH3 CH3CH2CH2CH3 CH3CH2CH3 CH3CH2CH2CH2CH3 correct answer: CH3CH2CH2CH3 What does a structural formula look like? correct answer: CH3CH2CH3 What is the molecular formula of a straight chain alkane with 12 carbon atoms? correct answer: C12H26 Which of the following alkanes would you expect to be a solid? C8H18 C20H42 CH4 C3H8 correct answer: C20H42 Carbon forms strong covalent bonds with each of the following elements ...