nutr chapter 9

• a metabolic pathway is a group of reactions that occur in a progression from begining to end
• anabolic pathways use small compounds to build larger/more complex ones and require energy
• catabolic pathways break down compounds don't need energy
• catabolic pathways capture energy in the form of adenosine triphosphate (atp)
• atp breaks down into adp then amp
• oxidation-reduction reactions form water and release energy used to produce oxygen and atp
• oxidize= lose electrons
• reduced=gain electrons
• niacin and riboflavin are the b vitamins we must get from diet
• lactate can be oxidized back into pyruvate
• 2 forms of cellular respiration= aerobic and anaerobic
• 4 stages of aerobic cellular respiration are glycolysis, transition reaction: synthesis of acetyl-coa, citric acid cycle, electron transport chain
• glycolysis produces two molecules of atp and occurs in the cytosol
• glycolysis starts with glucose and ends with pyruvate
• transition reactions convert pyruvate to acetyl-coa and occurs in mitochondria
• the citric acid cycle has potential atp and requires two turns to produce 1 glucose
• electron transport chain is were oxiative phosphorylation takes place and produces 28 atp
• anaerobic metabolism happens when cells don't have mitochondria or oxygen is lacking and pyruvate that is produced during glycolysis is now converted into lactate
• the conversion of pyruvate to lactate involves pyruvate dehyddrogenaase
• cori cycle transfers lacate from muscles to the liver
• atp production begins with lipolysis and continues with fatty acid oxidation
• cells can synthesize oxaloacetate to compensate
• if there's no insulin the result is diabetic ketoacidosis
• protein metabolism happens in the liver
• glucogenic amino acids use carbons from carbon skeletons to form glucose
• ketogenic amino acids use carbons to for acetyl-coa
• gluconeogenesis only happens in the liver and kidneys
• fatty acids can't be turned into glucose
• glycerol portion of triglyceride can form glucose
• first alc is turned into acetaldehyde which requires alcohol dehydrogenase then to acetyl-coa which requires aldehyde dehydrogenase
• pathways for lipogenesis are found in the liver
• some people lack enzymes to perform metabolic functions which cause inborn errors of metabolism
• phenylketonuria (pku) is a common inborn error of metabolism
• glycolysis doesn't require oxygen