#separator:Tab
#html:false
#tags column:5
IMF-089-01-0001-en	Why can failure of fat mobilisation or mitochondrial entry cause an energy crisis even when stored fat is abundant?	Fatty-acid oxidation is a key fuel during fasting and sustained exercise, and stored fat helps only if it is mobilised and enters mitochondria to be oxidised.	Integrated Medical Foundations; chapter 89, TTS module 1; https://theisegoria.github.io/medical-textbook/integrated-medical-foundations-expanded-english.md; module SHA256 at export: e88649afe4962d18fb428bbce0104f7cfacfad73f272c2c3fd797d34e0c597f8; editorial review pending	imf lang::en chapter::089 module::089-01 review::pending
IMF-089-01-0002-en	Why do lingual and gastric lipases matter mainly in infants or pancreatic insufficiency?	Most lipid digestion normally occurs in small intestine, where bile salts emulsify fat into small droplets and pancreatic enzymes hydrolyse ester bonds, so the earlier lipases otherwise contribute only modestly.	Integrated Medical Foundations; chapter 89, TTS module 1; https://theisegoria.github.io/medical-textbook/integrated-medical-foundations-expanded-english.md; module SHA256 at export: e88649afe4962d18fb428bbce0104f7cfacfad73f272c2c3fd797d34e0c597f8; editorial review pending	imf lang::en chapter::089 module::089-01 review::pending
IMF-089-01-0003-en	How do lipids and bile salts in mixed micelles behave differently at the enterocyte brush border?	Micelles carry digestion products through the unstirred aqueous layer; lipids leave them to enter cells, while bile salts stay in the lumen until distal reabsorption in terminal ileum for portal recycling.	Integrated Medical Foundations; chapter 89, TTS module 1; https://theisegoria.github.io/medical-textbook/integrated-medical-foundations-expanded-english.md; module SHA256 at export: e88649afe4962d18fb428bbce0104f7cfacfad73f272c2c3fd797d34e0c597f8; editorial review pending	imf lang::en chapter::089 module::089-01 review::pending
IMF-089-01-0004-en	How does the enterocyte repackage absorbed long-chain lipid for export?	Long-chain fatty acids and monoacylglycerols are re-esterified to triacylglycerol in endoplasmic reticulum, cholesterol is partly esterified, and microsomal triglyceride-transfer protein loads lipid onto apolipoprotein B-48 to form chylomicrons.	Integrated Medical Foundations; chapter 89, TTS module 1; https://theisegoria.github.io/medical-textbook/integrated-medical-foundations-expanded-english.md; module SHA256 at export: e88649afe4962d18fb428bbce0104f7cfacfad73f272c2c3fd797d34e0c597f8; editorial review pending	imf lang::en chapter::089 module::089-01 review::pending
IMF-089-01-0005-en	Why do chylomicrons initially bypass the liver, whereas short- and medium-chain fatty acids do not?	Chylomicrons leave through lymphatic lacteals and the thoracic duct into systemic blood, whereas short- and medium-chain fatty acids are more water soluble and travel directly in portal blood bound to albumin.	Integrated Medical Foundations; chapter 89, TTS module 1; https://theisegoria.github.io/medical-textbook/integrated-medical-foundations-expanded-english.md; module SHA256 at export: e88649afe4962d18fb428bbce0104f7cfacfad73f272c2c3fd797d34e0c597f8; editorial review pending	imf lang::en chapter::089 module::089-01 review::pending
IMF-089-01-0006-en	Why do pancreatic failure, deficient bile, ileal disease and lymphatic obstruction share a common clinical consequence?	Each disrupts a required step in lipid digestion, solubilisation, bile recycling or chylomicron export, so all cause fat malabsorption with fat-soluble-vitamin deficiency.	Integrated Medical Foundations; chapter 89, TTS module 1; https://theisegoria.github.io/medical-textbook/integrated-medical-foundations-expanded-english.md; module SHA256 at export: e88649afe4962d18fb428bbce0104f7cfacfad73f272c2c3fd797d34e0c597f8; editorial review pending	imf lang::en chapter::089 module::089-01 review::pending
IMF-089-01-0007-en	How does insulin steer chylomicron fatty acids toward adipose tissue after a meal?	Lipoprotein lipase on capillary endothelium hydrolyses chylomicron triacylglycerol for local uptake; insulin favours adipose lipoprotein-lipase activity after meals, while muscle takes fatty acids according to demand.	Integrated Medical Foundations; chapter 89, TTS module 1; https://theisegoria.github.io/medical-textbook/integrated-medical-foundations-expanded-english.md; module SHA256 at export: e88649afe4962d18fb428bbce0104f7cfacfad73f272c2c3fd797d34e0c597f8; editorial review pending	imf lang::en chapter::089 module::089-01 review::pending
IMF-089-01-0008-en	What switches adipose lipolysis on during fasting or exercise, and what switches it off?	Catecholamines and low insulin activate adipose triglyceride lipase and hormone-sensitive lipase through signalling and droplet remodelling; insulin suppresses lipolysis and promotes re-esterification.	Integrated Medical Foundations; chapter 89, TTS module 1; https://theisegoria.github.io/medical-textbook/integrated-medical-foundations-expanded-english.md; module SHA256 at export: e88649afe4962d18fb428bbce0104f7cfacfad73f272c2c3fd797d34e0c597f8; editorial review pending	imf lang::en chapter::089 module::089-01 review::pending
IMF-089-01-0009-en	Why is plasma non-esterified fatty acid a measure of flux rather than stores, and why does its level matter?	It reflects rapid flux, not the much larger stored pool; excessive release contributes to hepatic lipid accumulation and insulin resistance, while inadequate release limits fasting fuel.	Integrated Medical Foundations; chapter 89, TTS module 1; https://theisegoria.github.io/medical-textbook/integrated-medical-foundations-expanded-english.md; module SHA256 at export: e88649afe4962d18fb428bbce0104f7cfacfad73f272c2c3fd797d34e0c597f8; editorial review pending	imf lang::en chapter::089 module::089-01 review::pending
IMF-089-01-0010-en	Why is activating a fatty acid to acyl coenzyme A worth two high-energy phosphate equivalents?	Acyl-CoA synthetase converts ATP to AMP and pyrophosphate, and the resulting fatty acyl-CoA traps the fatty acid for oxidation, esterification, elongation or signalling.	Integrated Medical Foundations; chapter 89, TTS module 1; https://theisegoria.github.io/medical-textbook/integrated-medical-foundations-expanded-english.md; module SHA256 at export: e88649afe4962d18fb428bbce0104f7cfacfad73f272c2c3fd797d34e0c597f8; editorial review pending	imf lang::en chapter::089 module::089-01 review::pending
IMF-089-01-0011-en	Why does long-chain fatty acyl-CoA need carnitine to reach the mitochondrial matrix, and how does it cross?	It cannot cross the inner membrane; CPT1 on the outer membrane moves the acyl group to carnitine, a translocase swaps acylcarnitine in for free carnitine out, and CPT2 regenerates acyl-CoA in the matrix.	Integrated Medical Foundations; chapter 89, TTS module 1; https://theisegoria.github.io/medical-textbook/integrated-medical-foundations-expanded-english.md; module SHA256 at export: e88649afe4962d18fb428bbce0104f7cfacfad73f272c2c3fd797d34e0c597f8; editorial review pending	imf lang::en chapter::089 module::089-01 review::pending
IMF-089-01-0012-en	How does malonyl-CoA prevent fatty-acid synthesis and oxidation running at once, and how is the brake released in fasting?	Malonyl-CoA, made by acetyl-CoA carboxylase in the fed state, inhibits CPT1; in fasting or exercise AMP-activated kinase inhibits the carboxylase, malonyl-CoA falls, and oxidation rises.	Integrated Medical Foundations; chapter 89, TTS module 1; https://theisegoria.github.io/medical-textbook/integrated-medical-foundations-expanded-english.md; module SHA256 at export: e88649afe4962d18fb428bbce0104f7cfacfad73f272c2c3fd797d34e0c597f8; editorial review pending	imf lang::en chapter::089 module::089-01 review::pending
IMF-089-01-0013-en	In one beta-oxidation cycle, which steps generate reduced cofactors and which releases acetyl-CoA?	The first dehydrogenation passes electrons via FAD to electron-transfer flavoprotein, hydration adds water, the second dehydrogenation makes NADH, and thiolysis with CoA releases acetyl-CoA and a chain two carbons shorter.	Integrated Medical Foundations; chapter 89, TTS module 1; https://theisegoria.github.io/medical-textbook/integrated-medical-foundations-expanded-english.md; module SHA256 at export: e88649afe4962d18fb428bbce0104f7cfacfad73f272c2c3fd797d34e0c597f8; editorial review pending	imf lang::en chapter::089 module::089-01 review::pending
IMF-089-01-0014-en	What does complete oxidation of palmitate yield, and what does that yield depend on?	Seven cycles give eight acetyl-CoA, seven NADH and seven reduced flavin equivalents, roughly 106 ATP after activation cost, far more than glucose per molecule but only with oxygen and mitochondrial function.	Integrated Medical Foundations; chapter 89, TTS module 1; https://theisegoria.github.io/medical-textbook/integrated-medical-foundations-expanded-english.md; module SHA256 at export: e88649afe4962d18fb428bbce0104f7cfacfad73f272c2c3fd797d34e0c597f8; editorial review pending	imf lang::en chapter::089 module::089-01 review::pending
IMF-089-01-0015-en	If fat yields more energy per carbon, why can carbohydrate be advantageous when oxygen delivery limits exercise?	Fatty acids are highly reduced and stored without water, giving a high yield per carbon, but their oxidation consumes more oxygen per ATP than carbohydrate.	Integrated Medical Foundations; chapter 89, TTS module 1; https://theisegoria.github.io/medical-textbook/integrated-medical-foundations-expanded-english.md; module SHA256 at export: e88649afe4962d18fb428bbce0104f7cfacfad73f272c2c3fd797d34e0c597f8; editorial review pending	imf lang::en chapter::089 module::089-01 review::pending
IMF-089-01-0016-en	Why do odd-chain fatty acids provide limited net glucogenic carbon?	Their final propionyl-CoA is carboxylated by a biotin-dependent enzyme to methylmalonyl-CoA and converted by a vitamin B12-dependent mutase to succinyl-CoA, which replenishes cycle intermediates and can feed gluconeogenesis.	Integrated Medical Foundations; chapter 89, TTS module 1; https://theisegoria.github.io/medical-textbook/integrated-medical-foundations-expanded-english.md; module SHA256 at export: e88649afe4962d18fb428bbce0104f7cfacfad73f272c2c3fd797d34e0c597f8; editorial review pending	imf lang::en chapter::089 module::089-01 review::pending
IMF-089-01-0017-en	Why does the first step of peroxisomal very-long-chain fatty-acid oxidation yield no respiratory energy?	It transfers electrons directly to oxygen, producing hydrogen peroxide that catalase removes; the shortened chains are then passed to mitochondria for completion.	Integrated Medical Foundations; chapter 89, TTS module 1; https://theisegoria.github.io/medical-textbook/integrated-medical-foundations-expanded-english.md; module SHA256 at export: e88649afe4962d18fb428bbce0104f7cfacfad73f272c2c3fd797d34e0c597f8; editorial review pending	imf lang::en chapter::089 module::089-01 review::pending
IMF-089-01-0018-en	Why must phytanic acid undergo alpha oxidation, and what happens when this fails?	Its methyl group blocks conventional beta oxidation, so it is handled by peroxisomal alpha oxidation; defects cause accumulation affecting retina, peripheral nerves, cerebellum, skin, hearing and heart.	Integrated Medical Foundations; chapter 89, TTS module 1; https://theisegoria.github.io/medical-textbook/integrated-medical-foundations-expanded-english.md; module SHA256 at export: e88649afe4962d18fb428bbce0104f7cfacfad73f272c2c3fd797d34e0c597f8; editorial review pending	imf lang::en chapter::089 module::089-01 review::pending
IMF-089-01-0019-en	What does newborn screening for medium-chain acyl-CoA dehydrogenase deficiency make possible, and why does it matter?	The defect impairs oxidation during fasting or illness, causing hypoketotic hypoglycaemia, lethargy, seizures and liver dysfunction, so early detection permits preventive avoidance of prolonged fasting.	Integrated Medical Foundations; chapter 89, TTS module 1; https://theisegoria.github.io/medical-textbook/integrated-medical-foundations-expanded-english.md; module SHA256 at export: e88649afe4962d18fb428bbce0104f7cfacfad73f272c2c3fd797d34e0c597f8; editorial review pending	imf lang::en chapter::089 module::089-01 review::pending
IMF-089-01-0020-en	Why can primary carnitine deficiency cause cardiomyopathy and hypoketotic hypoglycaemia?	It impairs tissue carnitine uptake, so long-chain acyl groups cannot be carried into mitochondria for oxidation, producing low plasma carnitine, cardiomyopathy, weakness and hypoketotic hypoglycaemia.	Integrated Medical Foundations; chapter 89, TTS module 1; https://theisegoria.github.io/medical-textbook/integrated-medical-foundations-expanded-english.md; module SHA256 at export: e88649afe4962d18fb428bbce0104f7cfacfad73f272c2c3fd797d34e0c597f8; editorial review pending	imf lang::en chapter::089 module::089-01 review::pending
IMF-089-01-0021-en	Why does failed fatty-acid oxidation cause hypoglycaemia with inappropriately low ketones?	Hepatic oxidation normally powers gluconeogenesis, and its acetyl-CoA activates pyruvate carboxylase and inhibits pyruvate dehydrogenase; without it gluconeogenesis loses energy and activation while peripheral glucose use continues.	Integrated Medical Foundations; chapter 89, TTS module 1; https://theisegoria.github.io/medical-textbook/integrated-medical-foundations-expanded-english.md; module SHA256 at export: e88649afe4962d18fb428bbce0104f7cfacfad73f272c2c3fd797d34e0c597f8; editorial review pending	imf lang::en chapter::089 module::089-01 review::pending
IMF-089-01-0022-en	How does training let muscle preserve glycogen at a given workload?	Training increases mitochondrial density, capillaries, transport proteins and the capacity to oxidise fat, so more of the fuel at that workload comes from fatty acids.	Integrated Medical Foundations; chapter 89, TTS module 1; https://theisegoria.github.io/medical-textbook/integrated-medical-foundations-expanded-english.md; module SHA256 at export: e88649afe4962d18fb428bbce0104f7cfacfad73f272c2c3fd797d34e0c597f8; editorial review pending	imf lang::en chapter::089 module::089-01 review::pending
IMF-089-01-0023-en	Why does abundant intramyocellular lipid in endurance-trained muscle not by itself imply insulin resistance?	Trained muscle can hold substantial lipid while staying insulin sensitive, because toxicity relates to mismatched supply and disposal accumulating diacylglycerols, ceramides or incompletely oxidised products, not neutral triacylglycerol quantity.	Integrated Medical Foundations; chapter 89, TTS module 1; https://theisegoria.github.io/medical-textbook/integrated-medical-foundations-expanded-english.md; module SHA256 at export: e88649afe4962d18fb428bbce0104f7cfacfad73f272c2c3fd797d34e0c597f8; editorial review pending	imf lang::en chapter::089 module::089-01 review::pending
IMF-089-01-0024-en	Why does diagnosis of a suspected block in lipid fuel supply combine timing, ketones and specialised tests?	A block at any boundary, from intestinal absorption to mitochondrial enzymes, can resemble fuel scarcity, so timing with fasting or exercise, ketones, glucose, lactate, ammonia, acylcarnitines, organic acids, enzymes and genetics are used together.	Integrated Medical Foundations; chapter 89, TTS module 1; https://theisegoria.github.io/medical-textbook/integrated-medical-foundations-expanded-english.md; module SHA256 at export: e88649afe4962d18fb428bbce0104f7cfacfad73f272c2c3fd797d34e0c597f8; editorial review pending	imf lang::en chapter::089 module::089-01 review::pending