What is the total ATP yield per glucose molecule in carbohydrate metabolism?
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36 ATP
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What is the total ATP yield per glucose molecule in carbohydrate metabolism?
36 ATP
How many ATP molecules are produced from 10 NADH during the electron transport chain?
30 ATP
How many ATP molecules are produced from 2 FADH2 during the electron transport chain?
4 ATP
What is the role of NADH in carbohydrate metabolism?
NADH is used to transport electrons from the cytoplasm to the mitochondria.
What are the primary systems involved in the physiological response to exercise?
Cardio-respiratory and metabolic systems.
What is the intermediate product formed when pyruvate is converted to Acetyl CoA?
NADH and CO2
How does oxygen consumption change from rest to strenuous exercise?
It increases from approximately 250 ml/min at rest to over 4000 ml/min during strenuous exercise.
What is the main cycle involved in the metabolism of Acetyl CoA?
Krebs Cycle
What happens to minute ventilation at the initiation of exercise?
It increases dramatically from a basal rate of approximately 5 l/min to over 20 l/min.
What is the initial substrate in glycolysis?
Glucose
What causes the initial increase in minute ventilation during exercise?
Afferent impulses from proprioceptors in muscle.
What are glycogenic amino acids?
Amino acids that can be converted into glucose through gluconeogenesis.
How many ATP molecules are produced directly from glycolysis per glucose molecule?
2 ATP
What is VO2 max?
The maximum amount of oxygen a subject can utilize at a cellular level to produce ATP to power exercise, measured in ml/kg/min.
What is the role of the Electron Transport Chain in metabolism?
It produces water (H2O) by combining O2 with 2H+ and generates ATP.
What hormonal changes occur during the first 24 hours of starvation?
Insulin secretion is reduced and glucagon is secreted.
What are the five phases of the cardiac cycle?
Phase 1: atrial contraction, Phase 2: ventricular isovolumetric contraction, Phase 3: ventricular ejection, Phase 4: ventricular isovolumetric relaxation, Phase 5: passive ventricular filling.
What are carbohydrates made up of?
Carbon, hydrogen, and oxygen.
What happens to cardiac output during exercise?
It increases due to a rise in heart rate and augmentation of stroke volume.
What is the end product of glycolysis?
Pyruvate molecules.
What metabolic process is initiated by the secretion of glucagon during starvation?
Mobilisation of triacylglycerols in fat and gluconeogenesis by the liver.
What occurs during Phase 1 of the cardiac cycle?
Atrial contraction.
What are the two forms in which carbohydrates are consumed in the diet?
Simple sugars (glucose and fructose) and complex sugars (starch and cellulose).
What are the effects of the sympathetic nervous system on the heart during exercise?
It causes chronotropic (heart rate) and inotropic (force of systolic contraction) effects.
What is Acetyl CoA's role in metabolism?
It enters the Krebs Cycle to produce energy.
What is the formula for mean arterial pressure (MAP)?
MAP = Cardiac Output (CO) × Systemic Vascular Resistance (SVR)
What happens to the concentrations of acetyl-CoA and citrate during the first 24 hours of starvation?
Concentrations of acetyl-CoA and citrate rise, which reduces glycolysis.
What occurs during Phase 2 of the cardiac cycle?
Ventricular isovolumetric contraction.
What is the purpose of complex sugars in plants and animals?
In plants, they form structures (e.g., cellulose), and in animals, they are stored as glycogen.
How does muscle blood flow change during exercise?
It increases due to the accumulation of metabolites such as adenosine and potassium.
What factors contribute to short-term regulation of blood pressure?
Arterial and cardiac baroreceptors, vasomotor centre in the nucleus tractus solitarius, parasympathetic and sympathetic discharge.
What is the process of glycogenesis?
The formation of glycogen from glucose.
How does muscle tissue adapt to the lack of insulin during starvation?
Muscle uptake of glucose reduces and muscle shifts to using fatty acids as fuel.
What occurs during Phase 3 of the cardiac cycle?
Ventricular ejection.
Where does the digestion of complex sugars begin?
In the mouth with mastication.
What happens to the oxyhaemoglobin dissociation curve during exercise?
It shifts to the right due to reduced local pH and increased temperature in exercising muscle.
What is gluconeogenesis?
The process of producing glucose from non-carbohydrate sources.
Which factors are involved in long-term regulation of blood pressure?
Neurohumoral, renal, metabolic, race, and genetic factors.
What are the main patient factors that increase the risk of postoperative nausea and vomiting (PONV)?
Female gender, non-smoker, previous PONV, history of motion sickness.
What happens to pyruvate during the first 24 hours of starvation?
Pyruvate is no longer converted into acetyl-CoA and is exported to the liver for conversion into glucose.
What occurs during Phase 4 of the cardiac cycle?
Ventricular isovolumetric relaxation.
What is the body's most readily available energy source?
Glucose.
Why is blood redistributed to the skin during exercise?
To enable heat loss.
Name some factors that can affect long-term blood pressure.
Sodium intake, atrial natriuretic peptide, bradykinin, nitric oxide, glucocorticoids, renal function, psychological stress, obesity, atherosclerosis, renin-angiotensin-aldosterone system.
What are the main anaesthetic factors that increase the risk of postoperative nausea and vomiting (PONV)?
Use of N2O, use of opiates, use of etomidate, use of neostigmine, hypotension.
What is glycolysis?
The breakdown of glucose to produce pyruvate and energy.
What are the primary fuels used by muscle during the first 24 hours of starvation?
Fatty acids.
What is the aim of glycolysis?
To split the 6-carbon sugar glucose into two molecules of the 3-carbon sugar pyruvate.
What occurs during Phase 5 of the cardiac cycle?
Passive ventricular filling.
What are the three main stages of glucose metabolism?
Glycolysis, the Krebs cycle, and oxidative phosphorylation and the electron transport chain.
What is gluconeogenesis?
The synthesis of glucose from pyruvate, lactate, glycerol, alanine, and glutamine.
How does the vasomotor centre in the nucleus tractus solitarius affect blood pressure?
It alters the balance between parasympathetic and sympathetic discharge, thereby altering heart rate, stroke volume, and systemic vascular resistance.
What is ketogenesis?
The production of ketone bodies from fatty acids and ketogenic amino acids.
What are the main surgical factors that increase the risk of postoperative nausea and vomiting (PONV)?
Middle ear surgery, ophthalmic surgery (especially squint-correction surgery), gynaecology surgery.
What enzyme converts glucose-6-phosphate to fructose-6-phosphate?
Phosphofructokinase.
What are the key metabolic changes in non-glucose dependent tissues during starvation?
They start using ketones and free fatty acids (FFA) as fuel.
When does the aortic valve open during the cardiac cycle?
During ventricular ejection (Phase 3).
What is glycolysis?
The generation of ATP from glucose molecules.
What are nausea and vomiting?
Nausea is the sensation of the need to vomit. Vomiting is the involuntary, forceful expulsion of gastric contents via the mouth.
Why does gluconeogenesis occur?
To provide glucose when the supply of dietary glucose runs out.
What is the primary source of fuel during the early stages of exercise?
Carbohydrate, stored as glycogen and liberated into glucose.
What role does sodium intake play in blood pressure regulation?
Sodium intake can affect long-term blood pressure.
Which cranial nerves are involved in the efferent pathway of vomiting?
Cranial nerves V, VII, IX, X, XII.
What is lipolysis?
The breakdown of triglycerides into glycerol and fatty acids.
What is the role of the Cori cycle during starvation?
Lactate produced by muscles is converted back into glucose in the liver.
How many ATP molecules are generated and used up during glycolysis?
Glycolysis generates four ATPs while two are used up, making a net gain of two ATPs.
What is gluconeogenesis?
The generation of glucose from substrates such as pyruvate.
When does the aortic valve close during the cardiac cycle?
At the end of ventricular ejection, beginning of ventricular isovolumetric relaxation (Phase 4).
What reflexes are elicited by a rapid fall in blood pressure, such as a sudden 2L blood loss?
The physiological response involves cardiovascular, neurohumoral, and renal compensatory mechanisms.
What is the chemoreceptor trigger zone (CTZ) and where is it located?
The CTZ lies in the floor of the fourth ventricle in the area postrema and is functionally outside of the blood-brain barrier. It contains dopamine (D2) and serotonin (5-HT3) receptors.
Where does gluconeogenesis mainly take place?
Mainly in the liver, and to a small extent, in the kidneys.
What happens to the metabolic substrate as glycogen stores become depleted during prolonged exercise?
The metabolic substrate switches to fatty acids.
How does obesity potentially affect blood pressure?
Obesity may affect blood pressure through a possible link to insulin resistance.
What is glycogenolysis?
The breakdown of glycogen to release glucose.
What are the higher cortical centers involved in nausea and vomiting?
Pain, fear, sight, smell, memory, anticipation.
What happens to pyruvate when oxygen supply is inadequate?
Pyruvate enters an anaerobic pathway and is converted into lactate (lactic acid).
What is glycogenesis?
The synthesis of glycogen to store glucose.
What are the heart sounds S1 and S2 associated with in the cardiac cycle?
S1 is associated with the closure of the atrioventricular valves at the beginning of ventricular systole, and S2 is associated with the closure of the aortic and pulmonary valves at the beginning of ventricular diastole.
What is the immediate response of the baroreceptor reflex activation due to reduced vessel stretch?
Reduced baroreceptor input leads to reduced afferent discharge in glossopharyngeal and vagus nerves, inhibiting the cardio-inhibitory centre and activating the vasomotor centre, resulting in increased sympathetic activity, increased force of cardiac contraction, tachycardia, and increased SVR.
What provides efferent input to the vomiting centre?
The chemoreceptor trigger zone (CTZ) provides efferent input to the vomiting centre, which is located in the medulla.
What is the net cost of synthesizing glucose from pyruvate in gluconeogenesis?
6 ATPs.
How many ATP molecules are generated when fat is fully oxidized via the Krebs cycle?
129 molecules of ATP.
What is the role of the renin-angiotensin-aldosterone system in blood pressure regulation?
It is one of the factors that can affect long-term blood pressure.
What stimulates the release of gastrin?
Cephalic phase, stomach distension, proteins in the stomach, and increased pH of chyme in the stomach.
What is the role of the chemoreceptor trigger zone in vomiting?
It detects toxins and opioids, triggering the vomiting response.
What is the net gain of ATP from anaerobic respiration of one glucose molecule?
Two ATPs.
What is glycogenolysis?
The breakdown of glycogen to liberate glucose.
What is the significance of the pressure changes in the left ventricle during the cardiac cycle?
The pressure changes in the left ventricle drive the opening and closing of the heart valves, ensuring unidirectional blood flow through the heart.
What are hepatic zones?
The liver acinus is divided into zones 1–3.
How does the cardiovascular system respond to a rapid fall in blood pressure?
There is a redistribution of cardiac output from the skin, muscle, and viscera to the brain and heart.
What are the sources of direct afferent input to the vomiting centre?
The vestibular system, peripheral pain pathways, intestinal chemoreceptors, and the cerebral cortex provide direct afferent input to the vomiting centre via cranial nerves VIII, IX, and X.
What is the approximate weight of an adult liver?
1800–2000 g.
Why is the rate of ATP re-synthesis from fat not important during high-intensity exercise?
Because it is too slow to be of great importance during high-intensity exercise such as sprinting.
What is the Cori cycle?
The process where lactate produced during anaerobic respiration is converted back to glucose in the liver.
What are the actions of gastrin?
Increases secretion of gastric juices, increases motility, encourages growth of mucosa, constricts lower oesophageal sphincter (LOS), and relaxes pyloric and ileocaecal sphincters.
Which cranial nerves are involved in the labyrinthine pathway of vomiting?
Cranial nerve VIII.
What is the most important metabolic change after 72 hours of starvation?
The hepatic production of large amounts of ketone bodies (acetoacetate and 3-hydroxybutyrate) from acetyl-CoA.
What cycle does pyruvate enter when oxygen supply is adequate?
The Krebs cycle (also called the citric acid cycle or the tricarboxylic acid cycle).
What lipids does the liver synthesize?
Cholesterol and triglycerides.
What factors determine myocardial oxygen supply?
Coronary blood flow and arterial oxygen content (CaO2).
What composes the portal triad?
The hepatic artery, portal vein, and bile duct.
What are the two phases of vomiting?
The two phases of vomiting are the pre-ejection phase and the ejection phase.
What are the hypothalamic-pituitary-adrenal responses to a rapid fall in blood pressure?
Increased ADH secretion from the posterior pituitary leads to water conservation, and increased adrenal release of noradrenaline, adrenaline, and cortisol via sympathetic nervous system activation.
How is the liver anatomically divided?
Into right and left hemi-liver plus caudate lobe.
Under what conditions can protein be used to generate ATP?
In extreme conditions such as ultra marathon running or starvation.
How can amino acids provide a source of energy?
During their metabolism, intermediary products like pyruvate, acetyl CoA, and oxaloacetate are formed and fed into the Krebs cycle to yield ATP.
What stimulates the release of GIP (Gastric Inhibitory Peptide)?
Fatty acids in the small intestine.
Which cranial nerve is involved in the gastrointestinal (GIT) pathway of vomiting?
Cranial nerve X.
Why does the liver produce ketone bodies during prolonged starvation?
Because gluconeogenesis depletes the supply of oxaloacetate, which is essential for acetyl-CoA to enter the Krebs cycle, leading to ketogenesis.
What molecule does pyruvate convert into before entering the Krebs cycle?
Acetyl coenzyme A (acetyl CoA).
What ketone bodies are produced by the liver?
Acetoacetate and β-hydroxybutyrate.
What is coronary perfusion pressure (CoPP) and how is it calculated?
CoPP is the difference between aortic pressure and intraventricular pressure. It is calculated as CoPP = aortic pressure - intraventricular pressure.
What happens in the GI tract when a meal is anticipated?
The cephalic phase of gastric regulation is activated, involving the cerebral cortex, hypothalamus, medulla oblongata, and vagus nerve, leading to increased gastric juices and gastrin in the blood.
What forms the center of the acinus and zone 1?
The portal triad.
What occurs during the pre-ejection phase of vomiting?
During the pre-ejection phase, nausea occurs, sympathetic stimulation causes tachycardia, tachypnoea, and sweating, and parasympathetic stimulation causes salivation, relaxation of the upper and lower oesophageal sphincters, and giant retrograde contraction of the small intestine.
How do Starling's forces respond to a rapid fall in blood pressure?
They favor interstitial fluid movement into the circulation through a fall in intravascular hydrostatic pressure and a rise in oncotic pressure.
What is the histological unit of the liver?
The lobule.
What marks the onset of anaerobic metabolism during exercise?
The anaerobic threshold (AT), which occurs due to inadequate oxygen delivery.
What happens to glycerol when triglycerides are hydrolyzed?
Glycerol is fed into the Krebs cycle as dihydroxyacetone phosphate.
What are the actions of GIP?
Increases insulin release, inhibits secretion of gastric juices, and slows gastric emptying.
Which nerves are involved in the peripheral pain pathways of vomiting?
Spinal nerves.
What percentage of the brain's energy requirements is met by acetoacetate after 72 hours of starvation?
30%
Which vitamin does the liver activate?
Vitamin D.
What are the high-energy molecules generated during each turn of the Krebs cycle?
1 ATP, 3 NADH, and 1 FADH2.
Why does coronary blood flow to the left ventricle only occur during diastole?
During systole, the CoPP of the left ventricle can equal zero or less, preventing coronary blood flow.
What are the three main phases of gastric regulation?
Cephalic phase, gastric phase, and intestinal phase.
How does blood quality change from zone 1 to zone 3?
Blood becomes progressively poorer in oxygen and nutrients from zone 1 to zone 3.
What occurs during the ejection phase of vomiting?
During the ejection phase, respiration temporarily ceases mid-inspiration, the hyoid and larynx raise to open the crico-oesophageal sphincter, the glottis closes, the soft palate elevates to close off the nasopharynx, contraction of the diaphragm and abdominal muscles results in a rise in intra-abdominal pressure, the gastro-oesophageal sphincter opens, and gastric contents are ejected.
How does the Renin-Angiotensin-Aldosterone system respond to a fall in renal blood flow?
The juxtaglomerular apparatus releases renin, which converts angiotensinogen to angiotensin I. ACE converts this into angiotensin II, causing vasoconstriction and stimulating aldosterone release, which increases sodium and water re-absorption at the distal convoluted tubules, expanding plasma volume.
What shape are liver lobules?
Hexagonal.
What happens at the anaerobic threshold?
Lactate begins to accumulate in the blood.
What stimulates the release of secretin?
Acidic chyme in the small intestine.
What is glycogenesis?
The process of storing glucose as glycogen, primarily in the liver and muscles.
Which organs can use ketones as an energy source during starvation?
The brain and the heart.
What is the primary digestive function of the liver?
The liver produces bile, which is used for the emulsification of dietary lipids to allow their absorption.
How many times does the Krebs cycle turn for each molecule of glucose metabolized?
Twice.
How does heart rate affect coronary perfusion time?
As heart rate increases, diastolic time and therefore coronary perfusion time, especially to the left ventricle, is reduced.
What characterizes hepatocytes in zone 1?
They are close to the portal triad, surrounded by blood rich in oxygen and nutrients, and contain mitochondria-rich cells suited to oxidative metabolism and glycogen synthesis.
What is the Bainbridge reflex?
Also known as the atrial reflex, it is a rapid increase in heart rate due to increased venous return to the heart, aiming to restore atrial and vena caval pressures to normal.
What decreases the reflexes in the cephalic phase?
Stimulation of the sympathetic nervous system due to pain, fear, and anxiety.
What are the potential complications of vomiting?
Potential complications of vomiting include aspiration (particularly if GCS is reduced), wound dehiscence, electrolyte imbalance (loss of hydrogen, potassium, and chloride), dehydration, and elevated intraocular and intracranial pressure.
What components make up the portal triad?
Hepatic artery, portal vein, and bile duct.
What are the main energy stores in the body of a 70 kg male?
Carbohydrate, protein, and fat.
How is the anaerobic threshold measured?
In ml/kg/min of O2.
What triggers glycogenesis?
High amounts of glucose and ATP.
What are the actions of secretin?
Stimulates contraction of the gallbladder to release bile, stimulates release of pancreatic enzymes, and augments the effect of CCK.
What adaptation occurs in the brain several weeks into starvation?
Ketones become the major fuel source for the brain, providing more than 70% of its energy requirements.
What is the role of the electron transport chain in cellular respiration?
To use NADH and FADH2 generated in the Krebs cycle to make ATP.
Which fat-soluble vitamins require bile for absorption?
Vitamins A, D, E, and K.
How does atherosclerosis affect coronary vessel patency?
Atherosclerotic vessels are stenosed and have reduced blood flow.
What characterizes hepatocytes in zone 3?
They are at the periphery of the acinus, receive blood that has already undergone exchange of gases and metabolites, and are rich in smooth endoplasmic reticulum and cytochrome P450, making this the key region for drug and toxin biotransformation.
What is the Bezold–Jarisch reflex?
Activation of left ventricular chemo- and baroreceptors results in unopposed parasympathetic tone, leading to bradycardia, vasodilation, and hypotension, known as vasovagal syncope.
What triggers the cephalic phase of gastric regulation?
Thought, sight, and smell of food.
Where is the central vein located in a liver lobule?
In the center of the lobule, surrounded by hepatocytes.
How much energy is stored as glycogen in a 70 kg male?
1600 kcal.
At what percentage of VO2 max does the anaerobic threshold typically occur in healthy untrained individuals?
Between 45% and 65% of VO2 max.
What is glycogenolysis?
The breakdown of glycogen to release glucose.
What stimulates the release of CCK (Cholecystokinin)?
Amino acids and fatty acids in the small intestine.
How does the effective conversion of fatty acids into ketones by the liver affect muscle breakdown?
It reduces the need for glucose, thereby diminishing muscle breakdown.
What happens to electrons at the end of the electron transport chain?
They are accepted by oxygen molecules, which combine with H+ ions to form water.
How much glycogen does the liver store approximately?
Approximately 100 g.
What is the relationship between coronary vessel diameter and blood flow?
The wider the diameter, the greater the blood flow.
What happens during the gastric phase when food and fluid enter the stomach?
Stretch and chemoreceptors are activated, leading to increased gastric secretions, increased peristalsis, and increased tone of the lower oesophageal sphincter.
Which hepatic zone is most at risk of cellular damage during circulatory disturbances?
Zone 3.
What situations relevant to anesthesia can trigger the Bezold–Jarisch reflex?
Regional anesthesia (spinal, epidural, and interscalene blocks), hemorrhage/hypovolemia, and inferior vena cava compression in supine pregnant patients.
What is the function of sinusoids in the liver lobule?
They traverse the lobule, draining blood from the peripheral portal triads to the central vein.
How much energy is stored in mobilisable protein in a 70 kg male?
24,000 kcal.
What is the respiratory exchange ratio (RER)?
The ratio of CO2 production to O2 consumption (RER = VCO2/VO2).
What are the actions of CCK?
Stimulates contraction of the gallbladder to release bile, stimulates release of pancreatic enzymes, induces feeling of satiety, inhibits gastric emptying, and enhances actions of secretin.
What enzyme catalyzes the breakdown of glycogen during glycogenolysis?
Glycogen phosphorylase.
What determines the duration of starvation compatible with life?
The size of the triacylglycerol stores.
How many ATP molecules does the electron transport chain yield for each molecule of glucose?
34 ATP.
What other substances, besides glycogen, does the liver store?
Vitamins A, D, E, K, copper, and iron (as ferritin).
How does blood viscosity affect coronary blood flow?
As blood viscosity increases, flow decreases. Haematocrit is a major determinant of blood viscosity.
What happens when the pH in the stomach reaches 2 during the gastric phase?
Gastrin begins to exert a negative feedback to inhibit further acid secretion.
What is the blood supply rate to the liver?
100 ml/kg/min (approximately 1800 ml/min).
How is the Bezold–Jarisch reflex treated?
By restoring venous return with fluids and administering sympathomimetics, particularly ephedrine.
How much energy is stored in triacylglycerols in a 70 kg male?
135,000 kcal.
What type of cells are found in the sinusoids and are part of the reticuloendothelial system?
Kupffer cells.
What does the RER represent?
The metabolic exchange of gases in the body’s tissues, dependent on the predominant fuel used for cellular metabolism.
What is a sphincter?
A structure, usually made up of circular muscle, that surrounds the opening of a hollow organ or body and constricts to close it.
What hormones regulate glycogen synthesis and how?
Adrenaline stimulates glycolysis, glucagon stimulates glycolysis and inhibits glycogenesis, and insulin inhibits glycolysis and stimulates glycogenesis.
What happens during early starvation?
Reduction in energy expenditure, glycogen stores are used within 24 hours, and alternative fuels such as ketones are used to minimize protein wasting.
What is the capacitance function of the liver?
The liver can hold as much as 15% of the circulating blood volume and can act as a large blood reservoir.
What are the determinants of arterial oxygen content (CaO2)?
CaO2 = [Hb × SaO2 × 1.34] + [PaO2 × 0.023].
What percentage of the liver's blood flow comes from the portal vein and hepatic artery?
Approximately 70% from the portal vein and 30% from the hepatic artery.
What begins the intestinal phase of gastric regulation?
The entry of chyme into the duodenum.
What do hepatocytes produce and where is it excreted?
Hepatocytes produce bile, which is excreted into the hepatic ducts of the portal triad via the bile canaliculi.
What are the 24-hour energy requirements of a 70 kg male at rest?
1600–2000 kcal per 24 hours.
What are the types of sphincters in the gastrointestinal tract?
Upper oesophageal, lower oesophageal, pyloric, ileocaecal, sphincter of Oddi, and anus.
What happens to the VCO2 curve and RER once the anaerobic threshold is passed?
The VCO2 curve rises steeply, and the RER exceeds 1.0 due to additional non-metabolic CO2 production.
What happens during late starvation?
Fatty acids, ketones, and glycerol provide all of the energy requirements for the body, except for the brain and red blood cells, which still require a glucose source.
What is the role of Kupffer cells in the liver?
Kupffer cells remove old erythrocytes, bacteria, and other antigens via phagocytosis.
What are the major determinants of myocardial oxygen consumption?
Heart rate, contractility, afterload, tissue mass, and temperature.
What are the three main gut hormones secreted during the intestinal phase?
Gastric inhibitory peptide (GIP), secretin, and cholecystokinin (CCK).
How is the portal vein formed?
By the union of the splenic vein and superior mesenteric vein.
What is the functional unit of the liver?
The acinus.
How long do carbohydrate reserves (glycogen) last without energy intake?
Approximately 24 hours, less if exercising.
What is the function of the upper oesophageal sphincter?
It is under conscious control and constricts to avoid air being drawn into the stomach during breathing.
What are ALT and AST, and what do they indicate?
Alanine and aspartate aminotransferases (ALT and AST) are released into the blood following hepatocellular damage. ALT is more liver-specific than AST.
