Flashcards
MBM part 1
Cards in this deck (200)
- 1What type of Bonds join Amino Acids?Peptide bonds
- 2What type of bonds define the secondary structure of proteins?Hydrogen Bonds
- 3How many amino acids are there in a peptide?10
- 4What is the name for a structure containing more than 10 amino acids?A polypeptide
- 5What is the name given to amino acids in polypeptides?Residues
- 6What type of reaction forms peptide bonds?A condensation reaction (endergonic)
- 7How is the sequence of amino acids determined?It is genetically determined
- 8What kind of bonds can be formed between cysteine residues.Disulphide bonds
- 9List two properties of disulphide bonds in primary structure.1. they can be distant in primary structure
2. They can be formed between polypeptide chains. - 10Are primary and secondary structure bonds covalent?Primary structure - covalent peptide bonds
Secondary structure- non covalent ( no new bonds formed.) - 11How does secondary structure stabilise the polypeptide?Repeated hydrogen bonds.
- 12Describe the structure of an alpha helix.1. Right handed threaded
2. H-bonds every 4th residue
3. H bonds point in the same direction - 13Define Imino Acid.any molecule that contains both imino (>C=NH) and carboxyl (-C(=O)-OH) functional groups
- 14What produces a Kink in the alpha helix?Proline
- 15Outline the structure of a Beta-Pleated Sheet.1. Comprised of at least 2 beta strands
2. H-Bonds in between adjacent strands
3. each strand consists of consecutive amino acid residues
4. strands run parallel or antiparallel (see diagram on pg 16) - 16Define a Motif.Sequence motifs are short, recurring patterns in DNA that are presumed to have a biological function. Often they indicate sequence-specific binding sites for proteins such as nucleases and transcription factors )
- 17Describe tertiary structure of a protein.1. Packing of secondary structural elements.
2. describes the overall fold of a protein.
3. inexplicably linked to function
4. Stabilised by hydrophobic interactions - 18What are the names of the hydrophobic forces acting upon tertiary structure?1. Van Der Waals forces
2. Salt bridges
3. Ion pairs - 19What is the name describing what large proteins fold into?Domains
- 20How many residues are connected by flexible regions100-400
- 21What kind of proteins are formed in tertiary structure?Globular proteins, e.g globin.
- 22What causes proteins to be in a non function formation?Miss folding of the protein.
- 23How many amino acids are in a turn of a-helix3-6
- 24How many amino acids are in a turn of b-turn4-7
- 25What is Quaternary Structure?unique stable configuration. adopting the most thermodynamically stable form. mostly in proteins that have more than one polypeptide chain (subunit).
- 26What is a monomer?protein containing one sub-unit.
- 27What is an oligomer?Protein containing more than one sub-unit
- 28What is a Dimer?Protein containing two sub-units.
- 29What is a Tetramer?A protein containing 4 sub-units
- 30What is a Hexamer?A protein containing 6 sub-units
- 31What type of bond are sub-units held together by?Non-covalent interactions.
- 32How many subunits are there in haemoglobin?4 subunits: tetrameric protein
adults: a2b2
foetal: a2g2 - 33How many haem groups are there per subunit of haemoglobin?1 per subunit
- 34What is myoglobin?A red protein containing haem, which carries and stores oxygen in muscle cells. It is structurally similar to a subunit of haemoglobin
- 35How many residues does an alpha globin chain have?141 residues
- 36How many residues does a beta globin chain have146 residues
- 37How many of the alpha and beta globin chain residues are identical?64 residues
- 38How many alpha and beta globin chains as well as myoglobin residues are identical?28 residues
- 39What is positive co-operativity in O2 binding?When a sigmoidal curve of )2 binding is formed for Hb VS Mb.
This allows Hb to be fully oxygenated at the pO2 of the lungs and release 30-40% of O2 in lower pO2 of tissue - 40Define Globular ProteinCompact, buried hydrophobic core, soluble, e.g. many enzymes, globin
- 41Define Fibrous ProteinElongated, "soluble", contains repeated amino acid sequences, e.g. collagen, other connective tissue
- 42Describe features of membranesinsoluble, regions of exposed hydrophobic residues interact with membrane.
- 43Outline properties of intrinsic membrane proteins1.Part of the polypeptide chain in the membrane
2. Have hydrophobic domains in membrane bilayer, mostly alpha helix. - 44Outline properties of extrinsic membrane proteinsAssociated with membrane surface
- 45What are the conditions that cause denaturation of proteins?High temperature, extreme pH, denaturing agents (e.g. urea)
- 46How does a mutation in the primary structure of a protein affect it?It changes protein structure and activity
- 47What is conservative substitution of amino acids?The substitution of one amino acid for another with similar chemical properties
- 48Define glycosylationAddition of CHO to protein
- 49Define UbiquitylationAddition of ubiquitin.
- 50What is the action of Angiotensin II?1. Vasoconstriction
2. increased blood pressure - 51What is the action of ACE inhibitors?Decreases the rate of Angiotensin II production.
- 52Define isoenzymeEnzymes that differ in amino acid sequence but catalyse the same chemical reaction.
- 53How can you diagnose myocardial infarction using enzymes?Heart tissue is the only tissue that contains more than 5% of the total CK and CK2. presence of CK2 in plasma shows MI
- 54What are enzymes?Protein catalysts, they increase the rate of reaction without being changed in the overall process
- 55What are some properties of enzymes?1. Highly specific
2. make reactions a lot faster
3. have a specific 3D active site. - 56How do enzymes work?They lower the activation energy of the reaction so less energy is needed for the reaction to take place.
- 57What is the chemistry of the active site?Act as a template by binding the substrate to its surface and stabilising transition state intermediate so the reaction can occur at a lower energy. They also provide catalytic groups.
- 58What are the factors affecting the reaction rate?1. Substrate/enzyme concentration
2. Temperature
3. pH
4. Co-enzyme concentration
5. presence of inhibitors. - 59How does substrate concentration change reaction velocity?The rate of enzyme-catalysed reaction increases with substrate concentration until maximal velocity is reached (there are other limiting factors (e.g enzyme conc)
- 60How does temperature change reaction velocity?Increase in rate of reaction with an increase in temperature, until a temperature in which the enzymes denature.
- 61How does pH change reaction velocity?The pH optimum differs with specific enzymes. H+ affects reaction rate. the enzyme and substrate have specific groups that need to be ionized. extreme pH can denature enzymes.
- 62What is an enzyme co factors?A non protein molecule that aids in the function of an enzyme, normally metal ions. e.g. Fe2+
- 63What is a coenzyme?A non protein molecule that aids in the function of an enzyme. It is an organic molecule, usually a derivative of vitamins. e.g Vitamin A,D,E,K.
- 64How do you measure the progress of an enzyme reaction?Alcohol dehydrogenase
- 65What is the michaelis menten equation?
- 66what does each symbol mean?V= velocity
Vmax= maximal velocity
Km= substrate conc at 1/2 Vmax
Low Km= high affinity of E for S
High Km= Low affinity of E for S - 67What is the lineweaver-burke plot equation?in the form y=mx+c ( to find the points on the graph)
- 68What is the lineweaver-burke plot?
- 69What is an enzyme inhibitor?Substances that reduce an enzymes activity, influencing binding and/or its turnover number.
- 70What are the different types of enzyme inhibitor?They can be competitive or non-competitive
- 71Describe the action of a competitive enzyme inhibitor.A substance that competes directly with the substrate for the enzymatic binding site.
- 72What are the properties of a competitive enzyme inhibitor?1. usually resembles the substrate
2. binds to the active site
3. unreactive - 73Describe the action of a non-competitive enzyme inhibitor?A non-competitive inhibitor binds to the enzyme away from the active site, altering the shape of the enzyme so that even if the substrate can bind, the active site functions less effectively. Most of the time, the inhibitor is reversible.
- 74Name two examples of irreversible inhibitors.1. Nerve agent sarin- prevents acetylcholine hydrolysis
2. penicillin- affects manufacture of bacterial cell wall. - 75Describe acute enzyme regulation.Mostly change to the enzyme and therefore specific activity. Product inhibition. The product binds to the enzyme and prevents further production of the product
- 76Define an Allosteric enzyme.Mostly subunit enzymes with multiple active sites and sites for effector molecules. Regulated by molecules called effectors. can bind molecules as well as substrates, but binding of these molecules can inhibit substrate binding.
- 77What are the functions of negative and positive effectors?Positive effectors: increase enzyme activity at one type of active site
Negative effectors: inhibit enzyme activity at a particular active site. - 78What is a homotropic effector?Substrate serves as the effector. It is a positive effector, so S at one site on enzyme enhances catalytic properties. Co-operativity.
- 79What is an example of a homotropic effector?Oxygen binding to haemoglobin, it makes it have a higher affinity for the oxygen.
- 80Outline what a Heterotrophic effector is.The effector is not the substrate
- 81Define isoenzyme.Each of two or more enzymes with identical function but different structure.
- 82Outline what is meant by acute enzyme regulation.It is mostly change to enzyme (specific) activity. Products are inhibited from being produced.
- 83Outline what is meant by chronic enzyme regulation.Controlled by the amount of enzyme in the cell. Gene expression vs protein degradation.
- 84What is an allosteric enzyme?an enzyme that contains a region to which small, regulatory molecules ("effectors") may bind in addition to and separate from the substrate binding site and thereby affect the catalytic activity. They are mostly multi subunit enzymes with multiple active sites.
- 85Define covalent modification of enzymes.The addition and removal of P (phosphate) groups.
- 86Define phosphorylation.Addition of a phosphate group to a molecule.
- 87Define dephosphorylation.Removal of a phosphate group.
- 88what is serum?Serum is the clear liquid(which contain electrolyte, proteins, antibodies, hormones, exogenous substances) you get after you spin blood that has coagulated. It doesn't contain any cell nor clotting factors, which makes it quite different from blood plasma.
- 89What does ATP stand for?Adenosine Triphosphate.
- 90What does ATP hydrolysis result in?ADP+ inorganic Pi
- 91What is the general formula for a carbohydrate?(CH2O)n
- 92What is the general structure of carbohydrates?
- 93Define enantiomers.
- 94What is the most abundant carbohydrate found in the human body?Glucose, C6H12O6.
- 95How is glucose stored in human tissue?It is stored as glycogen.
- 96Why cant glucose be stored as glucose in the human tissue?Glucose is an osmotic molecule, meaning it would cause water to go in to the cells and damage them.
- 97What are the names of bonds that hold different carbohydrates together?Glycosidic bonds. (a1-4)(a1-6)
- 98Define saccharide.Another term for sugar/carbohydrate.
- 99Define polysaccharide.A carbohydrate (e.g. starch, cellulose, or glycogen) whose molecules consist of a number of sugar molecules bonded together.
- 100Define amylase.An enzyme, found chiefly in saliva and pancreatic fluid, that converts starch and glycogen into simple sugars.
- 101Define oligosaccharides.a carbohydrate whose molecules are composed of a relatively small number of monosaccharide units.
- 102Describe how carbohydrates are digested in the body.1. Starts in the mouth. Salivary amylase breaks down polysaccharides in to oligosaccharides.
2. further digestion in small intestine by pancreatic enzymes.
3. final digestion in to di/monosaccharides by enzymes on mucosal cells. - 103Describe glucose uptake.It is taken up into the cells via facilitated diffusion. They are aided by hexose transporter proteins in cell membrane (GLUT's). Insulin increases activity/expression of GLUT4
- 104How is glucose homeostasis maintained.Blood glucose concentrations regulated by opposing actions of the hormones, insulin and glucagon. They are both released by the pancreas.
- 105What is the function of insulin?Insulin is released in hyperglycaemia (high blood sugar levels). It promotes glucose uptake into the cells and storage.
- 106What is the function of glucagon?Glucagon is released when blood glucose is low, Hypoglycaemia. Promotes release of glucose from the liver into the blood.
- 107Outline the process of glycolysis.6 carbon glucose is converted into molecules of 3 carbon pyruvate (aerobic glycolysis) or lactate (anaerobic glycolysis)
- 108What is the net yield f ATP in glycolysis.Net yield of 2. 2 are used in the process and 4 are released.
- 109What else is created in glycolysis?2 NADH, which inn turn can yield 3 ATP.
- 110What is the first step of glycolysis?1. following uptake of glucose, its phosphorylated to Glucose-6-phosphate.
enzymes responsible: hexokinase and glucokinase - 111What is the second step of glycolysis?2. Glucose-6-phosphate is isomerised into fructose-6-phosphate.
enzyme responsible: Phosphoglucose isomerase - 112What is the third step of glycolysis?3. Phosphorylation of F6P into in to F1,6-BP (fructose-1,6-bisphosphate).
it is regulated by phosphofructokinase-1. - 113What is the fourth step of glycolysis?4. F1,6-BP is cleaved by aldolase. the products are glyceraldehyde 3-phosphate (GAP) and dihydroxyacetone phosphate (DHAP)
- 114What is the fifth step of glycolysis?5. It is an oxidation coupled with a phosphorylation reaction. 2 H+ from electrons of 2 GAP bind to 2 NAD+ to form 2 NADH. A phosphate is added to each GAP forms 1,3 Bis-phosphoglycerate.
- 115What is the sixth step of glycolysis?6. A high energy phosphate is transferred from 1,3 -BPG to ADP, forming 3-phosphoglycerate (3PG) and ATP. 2 ATP are made for each molecule of glucose.
- 116What is the seventh step of glycolysis?7. Phosphate moved from C3 to C2 to yield 2-phosphoglycerate. 2PG dehydrated to form phosphoenolpyruvate. The new rearrangement forms a high energy bond in PEP.
- 117What is the final step of glycolysis?8. Pyruvate Kinase converts PEP to pyruvate and at the same time transfers phosphate from PEP to ADP, forming ATP. 2 ATP generated for each glucose.
- 118Outline the whole process of glycolysis.
- 119What could cause high blood-lactose levels?Strenuous physical activity, sever lung disease, high altitude, severe anaemia, CO poisoning.
- 120What is the function of creatine phosphate?High energy intermediate in muscle that can transfer a phosphate to ADP to form ATP. It only lasts a few seconds.
- 121Which glycosidic bonds form linear chains?a1-4 glycosidic bonds.
- 122Which glycosidic bonds form branches away from the linear chain?a1-6 glycosidic bonds.
- 123Explain the process of glycogen synthesis.Glucose-6-phosphate converted into glucose-1-phosphate. glucose transferred to UTP (uridine triphosphate) to form UDP-glucose. Glycogen synthase creates a1-4 glycosidic bonds to add glucose to pre-existing glycogen fragment.
- 124Outline the term glycogenolysis.The process by which the glycogen present in the liver is transformed into glucose, to be released into the blood.
- 125Outline the process of glycogenolysis.Phosphorolysis of a1-4 glycosidic bonds by glycogen phosphorylase using inorganic phosphate to glucose-1-phosphate. It stops for units before the branch point of glycogen, resulting in "limit Dextrin". a debranching enzyme cleaves the a1-6 glycosidic bond to produce another glucose.
- 126Define a limit DextrinIt is the name given to the highly-branched core of the polysaccharide fragments remaining at the end (limit).
- 127Define fed state.The fed state refers to the period following a meal and is characterized by high levels of nutrients in the blood. There are high circulating levels of a family of simple sugars, the most important being glucose.
- 128When is glycogen synthesised in the body?normally synthesised during fed state in liver, and while resting in muscle.
- 129Define allosteric regulation of enzyme.In biochemistry, allosteric regulation (or allosteric control) is the regulation of a protein by binding an effector molecule at a site other than the enzyme's active site. The site to which the effector binds is termed the allosteric site.
- 130Describe the allosteric regulation of glycogen metabolism.High energy state- when, glucose, G6P and ATP are high, glucose phosphorylase is inhibited by G6P & ATP.
Low energy state- When glucose, G6P and ATP are low, glucose phosphorylase is activated by AMP. - 131What is glycogenolysis in the muscle activated by?Calcium.
- 132Explain how calcium in the muscle causes glycogenolysis.Muscle contraction results from increased cytosolic calcium. calcium binds to and activates phosphorylase kinase. This in turn phosphorylases and activates glycogen phosphorylase.
- 133What ae the main hormones responsible for glycogen metabolism?Insulin, glucagon and adrenaline.
- 134What is a G-Protein coupled receptor.G-protein-coupled receptors (GPCRs) are the largest and most diverse group of membrane receptors in eukaryotes. These cell surface receptors act like an inbox for messages in the form of light energy, peptides, lipids, sugars, and proteins.
- 135Where in the body does glycolysis occur?Cytosol- Any free cytoplasm.
- 136Where in the body does oxidation and the TCA cycle occur?The mitochondria.
- 137What process does pyruvate have to undergo before the TCA cycle (Tricarboxylic acid cycle/citric acid cycle) occurs?Pyruvate undergoes decarboxylation.
- 138What enzyme catalyses decarboxylation of pyruvate.pyruvate dehydrogenase.
- 139What is the first step of the formation of acetyl CoA from pyruvate?The decarboxylation of pyruvate into hydroxyethyl residue, using the enzyme TPP. CO2 also made.
- 140What is the second step of the formation of acetyl CoA from pyruvate?Oxidation of hydroxyethyl to acetylipoamide and transfer to CoA. this reaction is done using the protein lipoamide.
- 141What is the third step of the formation of acetyl CoA from pyruvate?Dihydrolipoyl transacetylase then transfers the activated acetyl group over to the CoA rom the lipoamide.
- 142What is the final step of the formation of acetyl CoA from pyruvate?regeneration of reduced lipoamide to oxidised lipoamide. This process uses FAD and converts it into FADH2. NAD+ is then needed to oxidise FADH2.
- 143What is the final equation for the formation of acetyl CoA?
- 144Outline the TCA cycle.
- 145What are the overall molecules created in the TCA cycle?3NADH
1FADH2
2CO2
1GTP
for each acetyl CoA oxidised. - 146Define oxidative phosphorylation.The process by which electrons are transferred from NADH and FADH2, through the electron transport chain to oxygen. The free energy released allows protons to be pumped across the intermembrane space and form a proton gradient. the proton gradient is then used to create ATP.
- 147What makes up the electron transport chain?Protein complexes, I, II, III, IV.
- 148How does complex I function?Complex I accepts electrons from NADH and moves them along the inner mitochondrial membrane to the final electron acceptor, namely oxygen. Turns NADH into NAD+
- 149How does complex II function?Complex II accepts electrons from FADH2 and moves them along the inner mitochondrial membrane to the final electron acceptor, namely oxygen. Turns FADH2 into FAD
- 150How is ATP synthase used in oxidative phosphorylation?The protons that are pumped into the intermembrane space by complexes I, III and IV can travel back down the proton gradient into the matrix though the protein ATP synthase. This give the protein the energy to phosphorylate ADP into ATP.
- 151What happens to oxygen during oxidative phosphorylation?It is reduced to form H2O, using the electrons.
- 152What is the first step of oxidative phosphorylation?electrons are removed from the NADH and the FADH2 molecule and travel through various complexes into the electron transport chain
- 153What is the second step of oxidative phosphorylation?This movement of electrons gives certain complex proteins ( I, III &IV) to pump protons (H+) into the intermembrane space. this establishes and electrochemical gradient for the protons.
- 154What is the third step of oxidative phosphorylation?the ATP synthase uses the energy stored in the electrochemical gradient, allowing protons to travel through it, down the electrochemical gradient. This energy phosphorylates the ATP molecules
- 155How many ATP can one molecule of NADH form?3
- 156How many ATP can one molecule of FADH2 form?2
- 157What is the net yield of ATP per glucose molecule?38 ATP molecules are created for every molecule of glucose.
- 158What agents affect oxidative phosphorylation?1. Inhibitors of the ATP synthase complex, e.g. oligomycin.
2. Site specific inhibitors of electron transport, e.g. rotenone.
3. Uncouplers, they neutralise proton gradient. - 159Define gluconeogenesis.The synthesis of glucose from non carbohydrate precursors.
- 160Give examples of non-carbohydrate pre-cursers used to make glucose.1. Lactate
2. Pyruvate
3. Glycerol
4. Amino Acid - 161Which types of cell can undergo gluconeogenesis?1. Liver cells
2. Hepatocyte
3. Kidney cells - 162What are the conditions for gluconeogenesis to take place?1. After exercise
2. Depleted glycogen stores
3. Trauma
4. Diabetes mellitus - 163Explain the Cori cycle- Lactate as a gluconeogenic precursor.
- 164Explain the alanine- glucose cycle.
- 165How does alcohol inhibit gluconeogenesis?Alcohol causes blood glucose levels to decrease dramatically, causing lack of energy.
- 166Define nitrogen balance.The difference between nitrogen intake in the diet (protein) and nitrogen excreted, mainly as urea.
- 167What is positive nitrogen balance?When nitrogen intake is greater than nitrogen loss (when you ingest more nitrogen than you excrete). This would occur for example in pregnancy, a growing child, in tissue repair after Injury.
- 168What is negative nitrogen balance?Less nitrogen intake than nitrogen output. Could occur in starvation, poor diet, illness.
- 169Define Kwashiorkor.A form of malnutrition caused by protein deficiency in the diet, typically affecting young children in the tropics.
- 170What are they key transporters in flow of nitrogen between the muscle and the liver?Glutamine and alanine
- 171Where is the site of amino acid catabolism?The liver.
- 172define catabolism.The breakdown of complex molecules in living organisms to form simpler ones, together with the release of energy; destructive metabolism.
- 173What are the steps in production of NH4+Transamination and oxidative deamination.
- 174Define transamination.Transfer of an amino acid group from one molecule to another, especially from an amino acid to a keto group.
- 175Define Oxidative Deamination.It is an oxidation reaction, which occurs under aerobic conditions in most tissues, and occurs largely on glutamic acid residues since glutamic acid is the end product of many transamination reactions
- 176Outline of the mechanism of transamination.1. alanine + a-ketoglutarate = pyruvate + glutamate. catalysed by alanine aminotransferase.
2. Aspartate + a-ketoglutarate = oxaloacetate + glutamate. Catalysed by Aspartate aminotransferase. - 177Outline the mechanism of oxidative transamination.1. Glutamate + NAD+ = a-ketoglutarate + NH4+ + NADH
- 178What does urea represent ?It represents the major nitrogenous product excreted in the urine. Its nitrogen is donated by ammonium ions and aspartate, while the carbon and oxygen are donated by bicarbonate.
- 179Outline the urea cycle.
- 180Define AlcaptonuriaAlkaptonuria (black urine disease, black bone disease, or alcaptonuria) is a rare inherited genetic disorder in which the body cannot process the amino acids phenylalanine and tyrosine, which occur in protein.
- 181Define Phenylketonuria.An inherited inability to metabolize phenylalanine which, if untreated, causes brain and nerve damage.
- 182Define Lipid.any of a class of organic compounds that are fatty acids or their derivatives and are insoluble in water but soluble in organic solvents. They include many natural oils, waxes, and steroids
- 183Define Adipose Tissue.A specialised cell containing a large droplet of lipid.
- 184What is the medical importance of lipids?They are a good energy source, utilised during fasting and starvation. One particular fatty acid is essential i.e. linoleate. overconsumption can cause health problems such as obesity.
- 185What is a saturated fatty acid?No double bonds in the alkyl chain of the fatty acid.
- 186What is an unsaturated fatty acid?one or more double bonds present in the alkyl chain of the fatty acid
- 187Define monounsaturated fatty acid.One double bond
- 188Define polyunsaturated fatty acid.Two or more double bonds.
- 189what is the fatty acid nomenclature?For the standard depicting way, see pg 83, pink highlight.
- 190What are some properties of fatty acids?Hydrophobic tail and hydrophilic head. this is called amphipathic (having both a hydrophobic and hydrophilic part. Lipids containing saturated fatty acids are often solids at room temperature. Lipids containing unsaturated fatty acids are often liquid at room temperature.
- 191What hormones mobilise fatty acids?Glucagon (starvation) and adrenaline (stress ) activate a hormone sensitive lipase which hydrolyses triacylglycerol in adipose tissue to free fatty acids and glycerol.
- 192Define peroxisome.Small organelle in the cytoplasm containing catalase anf some oxidases.
- 193How are long chain fatty acids transported in to the mitochondria?Long chain fatty acyl group transferred to carnitine in cytosol. LC fatty acyl carnitine transported into mitochondria- carnitine exported. LC fatty acyl group transferred to CoA. Short and medium fatty acids pass directly into the mitochondria where they are activated to fatty acetyl CoA.
- 194Define b-oxidation of fatty acids.Beta-oxidation is the catabolic process by which fatty acid molecules are broken down in the cytosol in prokaryotes and in the mitochondria in eukaryotes to generate acetyl-CoA, which enters the citric acid cycle, and NADH and FADH.
- 195Where does B-oxidation of fatty acids occur?The mitochondria.
- 196Can glucose be made from TAG?Triglycerides are made up of three units of fatty acids and one unit of glycerol. Glycerol is a component of fatty acids in fats that is released when stored fat is metabolized for energy. It then enters into the bloodstream and transferred to the liver where it can be converted to glucose.
- 197What are Ketone bodies?Three related compounds (one of which is acetone) produced during the metabolism of fats.
- 198Why are ketone bodies used?During starvation blood glucose drops very low, endangering the brain. Mobilisation of fatty acids from fatty acids (glucagon high). The brain cannot use fatty acids and the TCA cycle cant utilise all the acetyl CoA from b-oxidation. In the liver, acetyl CoA is diverted into ketone bodies which can be utilised by the muscle, kidney and eventually the brain.
- 199Define Ketosis.A condition characterized by raised levels of ketone bodies in the body, associated with abnormal fat metabolism and diabetes mellitus.
- 200Outline ketone body synthesis.
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- Year 1 Medicine (MBM) Flashcards on MBM part 1 , created by Dan Aduakwa on 18/07/2016.
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