met

Play an AI-generated podcast conversation about this lesson

What is the function of the Stem Cell in Gastric Pits?

To secrete HCL

To cover epithelium with mucous

To release hormone molecules

To repair damaged epithelium (correct)

What is the effect of prolonged vomiting on potassium levels?

No effect

Hyperkalemia

Electrolyte imbalance

Hypokalemia (correct)

What is the main composition of saliva secreted by the salivary glands?

HCO3

Amylase (correct)

HCL

Mucus

What is the function of the Parietal Cell in Gastric Pits?

To secrete HCL Signup and view all the answers

What is the main stimulant for gastric acid secretion?

Gastrin Signup and view all the answers

What is the name of the constriction in the oesophagus where it is pierced by the diaphragm?

Diaphragmatic constriction Signup and view all the answers

What is the main difference in the mucosa between the oesophagus and the stomach?

Stratified squamous to simple columnar/glandular Signup and view all the answers

Which part of the small intestine is primarily located in the left upper quadrant?

Jejunum Signup and view all the answers

What is the function of the pancreas in relation to the duodenum?

The pancreas empties all of its digestive enzymes into the duodenum Signup and view all the answers

What is the name of the glands found in the jejunum and ileum?

Peyer's glands Signup and view all the answers

What is the primary mechanism by which gastric contents flow back into the oesophagus in GORD?

Excessive reflux of normal gastric juice Signup and view all the answers

What is the major control point of glycolysis?

Phosphofructokinase Signup and view all the answers

Which of the following is NOT a characteristic of glucokinase?

High Km for glucose Signup and view all the answers

What is the primary role of the pentose phosphate pathway in relation to glycolysis?

Providing NADPH and ribose 5-phosphate Signup and view all the answers

What is the fate of pyruvate produced by glycolysis in the presence of oxygen?

Converted to acetyl-CoA and fed into the citric acid cycle Signup and view all the answers

What is the term for a condition where there is too little glucose in the blood?

Hypoglycaemia Signup and view all the answers

What happens to glucose in hepatocytes during glycogenesis?

It is stored in the form of glycogen Signup and view all the answers

What is the role of insulin in hepatocytes?

It accelerates glycolysis and promotes glycogen synthesis Signup and view all the answers

What is the result of excess ammonia in the body?

It depletes ketoglutarate used in the Krebs cycle Signup and view all the answers

What is the function of transaminase in protein metabolism?

It catalyzes the transfer of an amino group to a keto-acid Signup and view all the answers

What is the significance of high concentrations of ALT and AST?

It indicates hepatic injury Signup and view all the answers

What is the purpose of the urea cycle?

To remove ammonia from the body Signup and view all the answers

What is the primary function of apoproteins in lipoproteins?

To facilitate the transport of lipids through the bloodstream Signup and view all the answers

What is the main difference between chylomicrons and VLDL?

The source of the lipoprotein Signup and view all the answers

What is the fate of VLDL in the liver?

It is converted into LDL Signup and view all the answers

What is the purpose of packaging TAG into lipoproteins?

To facilitate the transport of TAG through the bloodstream Signup and view all the answers

What is the primary component of chylomicrons?

Triacylglycerol Signup and view all the answers

What is the role of lipoprotein lipase in lipoprotein metabolism?

To break down lipoproteins into smaller components Signup and view all the answers

What is the function of ICCs in the stomach?

Generating slow waves that propagate from the corpus Signup and view all the answers

What is the primary function of the fundus and body of the stomach?

Storing food due to receptive relaxation Signup and view all the answers

What is the significance of the greater curvature of the stomach?

It has a higher frequency of contraction Signup and view all the answers

What is the third phase of gastric motility?

Retropulsion Signup and view all the answers

What determines the rate of gastric emptying?

All of the above Signup and view all the answers

How do liquids empty from the stomach?

Exponentially Signup and view all the answers

What is the significance of the antrum in gastric motility?

It enables powerful contractions against a closed pylorus Signup and view all the answers

What happens to large solid particles in the stomach?

They suffer a lag phase Signup and view all the answers

What is the primary function of bile salts in the digestion process?

Emulsification of lipids to enhance absorption Signup and view all the answers

What is the primary site of cholesterol synthesis?

Liver Signup and view all the answers

What is the primary function of cholangiocytes in the bile duct?

Modulation of bile production by adding HCO3- Signup and view all the answers

What is the fate of bilirubin in the liver?

Excretion into the bile Signup and view all the answers

What is the primary stimulus for the secretion of bile from the gallbladder?

Presence of fatty acids in the duodenum Signup and view all the answers

What is the consequence of unchecked bile salt accumulation in the colon?

Diarrhea Signup and view all the answers

What is the primary mechanism of action of statins?

Inhibition of HMG-CoA reductase Signup and view all the answers

What is the primary function of conjugation of bilirubin with glucuronate?

Increased solubility of bilirubin Signup and view all the answers

What is the primary source of acetyl-CoA for extrahepatic tissues?

Ketone bodies Signup and view all the answers

What is the primary mechanism preventing fat oxidation when glucose is plentiful?

Increased malonyl-CoA levels Signup and view all the answers

What is the primary function of fructose 1,6-biphosphatase in gluconeogenesis?

To remove phosphate from sugar and dump it into water/cytoplasm Signup and view all the answers

What is the primary role of AMP-activated protein kinase (AMPK) in exercise?

Regulating fat oxidation Signup and view all the answers

Which of the following enzymes is involved in the conversion of pyruvate to PEP in gluconeogenesis?

Phosphoenolpyruvate carboxykinase Signup and view all the answers

What is the primary adaptation occurring during fatigue?

Increased fatty acid oxidation Signup and view all the answers

What is the byproduct of the reaction catalyzed by pyruvate carboxylase in gluconeogenesis?

CO2 Signup and view all the answers

Why is oxaloacetate not directly transported back into the cytoplasm in gluconeogenesis?

There is no oxaloacetate transporter in the mitochondria Signup and view all the answers

What is the primary fate of acetoacetate in the liver?

Split into ketone bodies Signup and view all the answers

What is the primary consequence of unregulated ketone production?

Ketoacidosis Signup and view all the answers

What is the purpose of malate dehydrogenase in gluconeogenesis?

To transport oxaloacetate back into the cytoplasm Signup and view all the answers

What is the result of fatty acid oxidation in the context of gluconeogenesis?

Production of ATP and NADH Signup and view all the answers

What is the primary source of energy for the brain during starvation?

Ketone bodies Signup and view all the answers

What is the primary mechanism by which AMP affects glucose handling in skeletal muscle?

Stimulating glycogen synthesis Signup and view all the answers

Why can fatty acids not be used to directly produce glucose?

Fatty acids are not a source of carbon skeletons Signup and view all the answers

What is the role of GTP in the conversion of oxaloacetate to PEP in gluconeogenesis?

GTP is used to drive the reaction of phosphoenolpyruvate carboxykinase Signup and view all the answers

What is the purpose of rearranging glucose-6-phosphate to fructose-6-phosphate in glycolysis?

To make the steps chemically easier Signup and view all the answers

What is the effect of high levels of ATP and citrate on the activity of Phosphofructokinase-1?

They inhibit the enzyme Signup and view all the answers

What is the product of the cleavage of fructose-1, 6-biphosphate in glycolysis?

Two 3-carbon molecules Signup and view all the answers

What is the role of glyceraldehyde phosphate dehydrogenase in glycolysis?

To oxidize glyceraldehyde-3-phosphate Signup and view all the answers

What is the function of phosphoglycerate kinase in glycolysis?

To phosphorylate ADP Signup and view all the answers

What is the fate of NADH in aerobic conditions?

It is fed into the respiratory chain Signup and view all the answers

What is the role of pyruvate kinase in glycolysis?

To convert PEP to pyruvate Signup and view all the answers

What is the significance of the conversion of fructose-6-phosphate to fructose-2,6-biphosphate?

It is a mechanism to regulate the concentration of fructose-6-phosphate Signup and view all the answers

What is the function of the migrating motor complex in the small intestine?

To clear undigested material and prevent bacterial growth Signup and view all the answers

What is the primary trigger for the contraction of the stomach during the gastric phase?

Mechanical effect of food in the stomach Signup and view all the answers

What is the role of enteric sensory neurons in the regulation of peristalsis?

To detect intraluminal stimuli and initiate peristalsis Signup and view all the answers

During swallowing, what is the function of the second peristaltic wave?

To back up the first peristaltic wave in case of obstruction Signup and view all the answers

What is the primary function of the cephalic phase of food intake?

To prepare the gastrointestinal tract for food intake Signup and view all the answers

What is the primary role of insulin in regards to glycogen synthesis?

It activates protein phosphatase-1 to increase glycogen synthase activity Signup and view all the answers

What is the mechanism by which the migrating motor complex clears undigested material from the small intestine?

By stimulating the contraction of the intestinal muscles Signup and view all the answers

What is the energy source for the conversion of glucose-1-phosphate to UDP-glucose?

UTP Signup and view all the answers

What is the primary function of glycogen phosphorylase in the liver?

To break down glycogen to release glucose into the blood Signup and view all the answers

What is the primary function of the gastric phase of food intake?

To stimulate the contraction of the stomach muscles Signup and view all the answers

What is the effect of phosphorylation on glycogen synthase activity?

It decreases glycogen synthase activity Signup and view all the answers

What is the role of the vagus nerve in the regulation of gastrointestinal motility?

To stimulate the contraction of the stomach and small intestine Signup and view all the answers

What is the primary role of glucagon in regards to glycogen metabolism?

It breaks down glycogen to release glucose into the blood when glucose levels are low Signup and view all the answers

What is the fate of glycogen breakdown in muscle cells?

It is fed into glycolysis and used for energy production in the muscle cell Signup and view all the answers

What is the primary function of glycogenin in glycogen synthesis?

It synthesizes glycogen from UDP-glucose Signup and view all the answers

What is the effect of dephosphorylation on glycogen synthase activity?

It increases glycogen synthase activity Signup and view all the answers

What is the primary mechanism by which the TCA cycle rate is controlled?

Availability of NAD+ Signup and view all the answers

What is the role of calcium in the TCA cycle in muscles?

It stimulates the activity of dehydrogenases Signup and view all the answers

What is the purpose of pyruvate carboxylase in the TCA cycle?

To top up oxaloacetate levels Signup and view all the answers

What is the effect of hypoxia on oxidative metabolism?

It decreases ATP production Signup and view all the answers

What is the role of HIF1 in hypoxia?

It inhibits biogenesis of mitochondria Signup and view all the answers

What is the consequence of reduced mitochondrial density in hypoxia?

It reduces oxidative stress Signup and view all the answers

What is the primary adaptation to hypoxia?

Increased anaerobic metabolism Signup and view all the answers

What is the role of gene expression changes in hypoxia?

They stimulate HIF1 activity Signup and view all the answers

What percentage of the liver's blood supply is derived from the portal circulation?

75% Signup and view all the answers

What type of muscle fiber uses oxidative metabolism from glucose and fatty acids?

Type 1 Slow Twitch Signup and view all the answers

What is the primary function of the hepatic lobule?

To metabolize carbohydrates, proteins, and fats Signup and view all the answers

What is the primary fuel source for Type 2 Fast Twitch muscle fibers?

Glycogen Signup and view all the answers

What is the primary fate of glucose in hepatocytes?

Glycogen synthesis Signup and view all the answers

What is the purpose of AMP in skeletal muscle during exercise?

Increase glucose uptake in the short term and FA oxidation in the long term Signup and view all the answers

What is the name of the vein that drains the liver and empties into the inferior vena cava?

Hepatic vein Signup and view all the answers

What is the role of calcium in muscle contraction?

Bind to calmodulin Signup and view all the answers

What is the function of the bile duct in the hepatic lobule?

To secrete bile into the small intestine Signup and view all the answers

What is the primary source of ATP replenishment during exercise?

Phosphocreatine Signup and view all the answers

What is the primary source of oxygenated blood to the liver?

Hepatic artery Signup and view all the answers

What is the result of a decrease in ATP levels during exercise?

Increase in ADP and AMP levels Signup and view all the answers

What is the term for the process of removing toxins from the blood?

Detoxification Signup and view all the answers

What type of metabolism is used by Type 2 Fast Twitch muscle fibers?

Anaerobic metabolism Signup and view all the answers

What is the primary function of the gallbladder?

To store bile produced by the liver Signup and view all the answers

What is the function of phosphorylase kinase in muscle contraction?

Activate glycogen phosphorylase Signup and view all the answers

What is the primary mechanism of IgA transport across the epithelium in the gut?

The polymeric Ig receptor Signup and view all the answers

What is the role of MadCAM in the gut?

Ligand for alpha 4 beta 7 Signup and view all the answers

What is the function of the J chain in IgA and IgM?

Joining chain Signup and view all the answers

Why is IgA not a good mediator of inflammatory reactions?

Agglutination mechanism Signup and view all the answers

What is the role of breast endothelial cells in lactation?

Expressing MadCAM and facilitating IgA transport Signup and view all the answers

What is the significance of IgA production in the gut?

Provides effective immunity against pathogens Signup and view all the answers

What is the primary mechanism by which high glucose conditions inhibit fat oxidation?

High glucose conditions lead to increased citrate levels, which are then converted to malonyl-CoA, inhibiting the uptake of fatty acids by the mitochondria. Signup and view all the answers

How does the brain adapt to starvation in terms of glucose and ketone body utilisation?

During starvation, the brain switches from using 100% glucose to using 50% ketone bodies. Signup and view all the answers

What is the consequence of depleted oxaloacetate levels in the liver?

Depleted oxaloacetate levels in the liver lead to the accumulation of acetyl-CoA, resulting in the production of ketone bodies. Signup and view all the answers

What is the role of AMP-activated protein kinase (AMPK) in exercise?

AMPK plays a regulatory role in exercise, promoting fat oxidation and glucose uptake in skeletal muscle. Signup and view all the answers

What is the fate of acetoacetate in extrahepatic tissues?

Acetoacetate is converted back to acetyl-CoA and used for the TCA cycle in extrahepatic tissues. Signup and view all the answers

What is the consequence of uncontrolled ketone production in the absence of insulin?

Uncontrolled ketone production in the absence of insulin can lead to ketoacidosis. Signup and view all the answers

What is the purpose of phosphofructokinase-1 in glycolysis, and how is it regulated?

Phosphofructokinase-1 is responsible for converting fructose-6-phosphate to fructose-1,6-biphosphate. It is regulated by high levels of ATP and citrate, which inhibit this step, indicating that the cell no longer needs to make ATP. Signup and view all the answers

What is the significance of the conversion of fructose-1,6-biphosphate to dihydroxyacetone phosphate and glyceraldehyde-3-phosphate in glycolysis?

The conversion of fructose-1,6-biphosphate to dihydroxyacetone phosphate and glyceraldehyde-3-phosphate is significant because it marks the point at which glycolysis has only used ATP and has not yet produced ATP. Signup and view all the answers

Describe the peripheral branches of the facial nerve and their role in muscles of facial expression.

The facial nerve has five peripheral branches: the temporal, zygomatic, buccal, marginal mandibular, and cervical branches. These branches are responsible for innervating the muscles of facial expression, which include the orbicularis oculi, zygomaticus major, buccinator, and others. Signup and view all the answers

Outline the peripheral course and distribution of the hypoglossal nerve, and its role in the motor innervation of the tongue.

The hypoglossal nerve emerges from the medulla oblongata and passes through the hypoglossal canal to reach the tongue. It innervates the extrinsic muscles of the tongue, including the genioglossus, hyoglossus, and styloglossus, which are responsible for tongue movements. Signup and view all the answers

What is the role of glyceraldehyde phosphate dehydrogenase in glycolysis, and what is the significance of NADH production in this step?

Glyceraldehyde phosphate dehydrogenase is responsible for oxidizing glyceraldehyde-3-phosphate to form 1,3-biphosphoglycerate, and in this step, NAD+ is reduced to NADH. The significance of NADH production is that it is required for the first ATP production in glycolysis. Signup and view all the answers

What is the role of phosphoglycerate kinase in glycolysis, and what is the significance of ATP production in this step?

Phosphoglycerate kinase is responsible for transferring a phosphate from 1,3-biphosphoglycerate to ADP to form ATP and 3-phosphoglycerate. The significance of ATP production in this step is that it marks the first point at which ATP is produced in glycolysis. Signup and view all the answers

Describe the anatomy and nervous innervation of the salivary glands and ducts.

The salivary glands, including the parotid, submandibular, and sublingual glands, are innervated by the parasympathetic and sympathetic nervous systems. The parasympathetic fibers stimulate salivary secretion, while the sympathetic fibers inhibit it. The ducts of the salivary glands transport saliva to the oral cavity. Signup and view all the answers

What is the fate of NADH in aerobic and anaerobic conditions, and what is the significance of this in terms of energy production?

In aerobic conditions, NADH feeds the respiratory chain, while in anaerobic conditions, NADH is regenerated to form lactate. The significance of this is that it allows the cell to adapt to different energy demands and produce ATP accordingly. Signup and view all the answers

Define the boundaries and describe the major features of the naso, oro, and laryngopharynx.

The nasopharynx extends from the base of the skull to the soft palate, the oropharynx extends from the soft palate to the epiglottis, and the laryngopharynx extends from the epiglottis to the cricoid cartilage. The pharynx is lined with mucous membrane and contains the tonsils and adenoids. Signup and view all the answers

Outline the nervous innervation of the pharynx, including the control of swallowing and the gag reflex.

The pharynx is innervated by the glossopharyngeal and vagus nerves, which control swallowing and the gag reflex. The glossopharyngeal nerve is responsible for the sensory innervation of the pharynx, while the vagus nerve is responsible for the motor innervation. Signup and view all the answers

What is the role of pyruvate kinase in glycolysis, and what is the significance of pyruvate production in this step?

Pyruvate kinase is responsible for converting phosphoenolpyruvate (PEP) to pyruvate, and in this step, ATP is produced. The significance of pyruvate production is that it marks the end of glycolysis and the beginning of the citric acid cycle or fermentation. Signup and view all the answers

Explain how the gastro-oesophageal junction contributes to the prevention of reflux.

The gastro-oesophageal junction, which is formed by the lower oesophageal sphincter and the crural diaphragm, prevents reflux by creating a high-pressure zone that prevents stomach contents from flowing back into the oesophagus. Signup and view all the answers

What is the role of calcium in the contraction of muscle fibers, and how does it relate to the breakdown of glycogen?

Calcium binds to the subunit calmodulin, which activates phosphorylase kinase, leading to the phosphorylation of glycogen phosphorylase, resulting in the breakdown of glycogen. Signup and view all the answers

How does the balance between type 1 and type 2 muscle fibers change in response to different types of exercise, and what are the implications for energy production?

The balance between type 1 and type 2 muscle fibers changes in response to different types of exercise, with type 1 fibers being more prevalent in endurance exercises and type 2 fibers in high-intensity exercises. This affects the primary source of energy, with type 1 fibers using oxidative metabolism and type 2 fibers using anaerobic metabolism. Signup and view all the answers

What is the role of AMP as a metabolic signal, and how does it influence glucose uptake and fatty acid oxidation?

AMP serves as a metabolic signal, increasing glucose uptake in the short term and fatty acid oxidation in the long term. Signup and view all the answers

How does the demand for ATP in skeletal muscle change during exercise, and what are the primary sources of ATP replenishment?

The demand for ATP in skeletal muscle increases significantly during exercise, and ATP can be replenished from phosphocreatine, glycogen, and triacylglycerol. Signup and view all the answers

What is the significance of the different types of muscle fibers in terms of their metabolic characteristics and exercise performance?

Type 1 slow-twitch muscle fibers use oxidative metabolism, are rich in mitochondria, and are suited for endurance exercises. Type 2 fast-twitch muscle fibers use anaerobic metabolism, are rich in glycogen, and are suited for high-intensity exercises. Signup and view all the answers

How does the metabolism of ethanol affect carbohydrate and fat metabolism, and what are the potential consequences for overall energy metabolism?

The metabolism of ethanol can alter carbohydrate and fat metabolism, leading to changes in blood glucose and lipid levels. This can have significant consequences for overall energy metabolism, particularly in individuals with compromised liver function. Signup and view all the answers