diabetestalk.net

Insulin Stimulates Quizlet

Insulin And Glucagon

Insulin And Glucagon

it helps keep blood sugar in check from being to high (hyperglycemia) when blood sugar rises, beta cells in the pancreas are signaled to release __________ into the system attaches to cells and signals for them to take in the glucose if there is more sugar than the body needs, ________ can also help store it in the liver which can be used when it is needed when glycogen is fully restored, ________ stimulates glycolysis to get rid of blood glucose which can be used to bump up some intermediates of the CAC even all the way down to the mitochondria, which can then make protein synthesis and fat metabolism easier the body can become resistant to or not produce enough ___________ if blood sugar levels remain too high for too long hyperglycemia) - ____________ resistance is another hormone responsible for maintaining proper blood sugar levels it is also produced in the pancreas but by the alpha cells the role of _______________ is to keep blood glucose levels from dropping too low _______________ secretion can be inhibited by raised blood sugar levels or high carbohydrate meals stimulates the liver to covert stored glycogen into glucose to be released into the bloodstream glucagon levels in the body can vary depending on the kind of meals we eat -high carbohydrate - lower levels of glucagon -high protein - higher levels of glucagon glucagon increases blood glucose in several ways: -stimulating the breakdown of liver glycogen -inhibiting glucose breakdown in the liver -stimulating gluconeogenesis in the liver (amino acids and glycerol) -the GLUT4 transporter is an insulin regulated transporter of glucose -insulin regulates the uptake of glucose into cells through this transporter -insulin stimulates the movement of the GLUT4 transporter to the surface of the cells to take in Continue reading >>

Bc 20 Flashcards | Quizlet

Bc 20 Flashcards | Quizlet

The Major Pathways of Energy Metabolism Must Adapt to the _____ Four major organs play a dominant role in energy metabolism The integration of energy metabolism is controlled primarily by the actions of two peptide hormones: ____ and ___, with the catecholamines _____ and _____ playing a supporting role. Insulin: is a hormone, secreted by the cells of pancreas, to lower blood sugar levels. Insulin is needed to convert sugar, starches, and other food into glucose (blood sugar) or regulates storage of glycogen in the liver and accelerates _____ in cells. Insulin stimulates _____and _____ while inhibits _____ and ____. Insulin: Being a protein, insulin is not orally active because it is destroyed by digestive enzymes, so mostly used as an ____. Insulin metabolic effects are _____, for example, synthesis of ____, _____, and ____. Insulin is a _____ hormone composed of __ amino acid residues and has a molecular weight of ____ Da. After a meal, the body is flooded with amino acids, monosaccharides and triglycerides. Not all of this can be oxidized immediately, and excess nutrients have to be stored as ____ and ____ Insulin is the hormone of the well-fed state. Its synthesis and release are stimulated by ____, and this effect is potentiated by amino acids. Therefore, the plasma level of insulin is highest after a carbohydrate-rich meal. During fasting, plasma level of insulin falls. Insulin stimulates the utilization of nutrients such as _____, ______, and _____. It diverts excess nutrients into the synthesis of glycogen, fat, and protein. Insulin regulates the metabolism of fat and protein as well as of carbohydrate. It induces the conversion of excess carbohydrate to fat by ______ and _____ _____is a polypeptide hormone secreted by the -cells of the pancreas that stimulates Continue reading >>

Biochem - Module 8 - Carbohydrate Metabolism

Biochem - Module 8 - Carbohydrate Metabolism

Sort What are the major functions (2) and metabolic pathways affected by insulin? (3) Functions 1) Promotes fule storage after a meal 2) Promotes growth metabolic pathways 1) Stimulates glucose storage as glycogen in the muscle and liver 2) Stimulates fatty acid synthesis and storage after a high carb meal 3) Stimulates amin acid uptake and protein synthesis how does glucose become pytuvate? a-glucose glucose 6-phosphate fructose 6-phosphate fructose 1,6 biphosphate glyceraldehyde 3-phosphate 1,3 biphosphyoglycerinate 3 biphosphyoglycerate 2 biphosphyoglycerate biphosphyonal - pyruvate pyruvate Hamsters love to run on exercise wheels. Prolonged running at a high rate of speed requires ATP. Could a hamster with a defective gene for the enzyme lactate dehydrogenase meet the extra ATP demand for prolonged, fast wheel-running by maintaining a high rate of glycolysis when muscles are operating under anaerobic conditions? No, not enough NAD+ can be regenerated from glycolysis to continue at a high rate Continue reading >>

Phys Exam 5: Regulation Of Metabolism

Phys Exam 5: Regulation Of Metabolism

- Normal fasting blood glucose = 70-110 mg/dL - Minimal glucose needed for brain = 40 mg/dL (below this cognitive deficits, even coma) - Saturating glucose concentration for renal proximal tubules = 180 mg/dL (no glucose in urine unless blood glucose is above this level) - Insulin is the most important regulator of plasma glucose concentration! - Absorptive state = elevated levels of insulin - Postabsorptive state = lowered levels of insulin - Secreted from Beta cells of pancreatic Iselts of Langerhans - Absorptive State: Increased blood glucose stimulates insulin secretion - Target cells express insulin receptor that responds to increase in plasma insulin concentration to stimulate storage of nutrients Preproinsulin: is an amino acid chain with a signaling sequence. Proinsulin: Signal sequence removed, insulin folded with C-chain connecting A-chain and B-chain, which are connected by disulfide bonds. Insulin: A-Chain and B-Chain, C chain has been removed. 1. Increases uptake of nutrients into tissues (mainly skeletal muscle and adipose tissue, NOT LIVER) 2. Stimulates synthesis of storage form of nutrients (Glycogen, protein, triglycerides) 3. Inhibits metabolism of stored nutrients (Glycogenolysis, proteolysis, lipolysis) Insulin does NOT increase liver uptake of glucose. Adipose tissue and muscle express insulin-responsive Glut4, liver does not. Insulin stimulates rate limiting enzyme for glycogen synthesis in muscle and liver. Protein is not storage form of energy, but it is important for maintaining cell health and function, so want to produce and conserve protein. Insulin stimulates amino acid uptake into liver and skeletal muscle and promotes protein synthesis (by stimulating ribosomal enzymes). Insulin also inhibits enzymes involved in protein catabolism. *Insu Continue reading >>

Ch 17 And 18

Ch 17 And 18

Sort -The stomach and intestinal tract converts food into glucose -Glucose from the stomach enters the blood stream -When glucose reaches the pancreas, it causes the pancreas to release insulin -Insulin causes its target cells to take-up glucose from the blood -Glucose is stored in the liver and muscles as glycogen and in adipose tissue as fat The pathway of glucose -decreased blood glucose -pallor, tremors, tachycardia, palpitations, diaphoresis, hunger -headache, dizziness, anxiety, irritability, fatigue -poor judgement, confusion visual disturbances, seizures -coma symptoms of hypoglycemia Continue reading >>

Insulin & Glucagon

Insulin & Glucagon

Sort What biological actions INCREASE due to glucagon? INCREASE IN: - Glycogenolysis - Gluconeogensis* - Fatty acid oxidation - Ketogenesis - uptake of AA (*Glucagon STIMULATES gluconeogenesis by increase gene expression of PEPCK. Does so by binding to CREB-P-a leucine zipper binding domain) Continue reading >>

Glucose Transport Flashcards | Quizlet

Glucose Transport Flashcards | Quizlet

major site = skeletal muscle, adipose tissue proposed function = insulin mediated glucose uptake GLUT 4= skeletal muscle and adipose tissue GLUT 2 = respond to blood glucose, B-cells release insulin How does glucose stimulate insulin release? GLUT2 transporters transport glucose to pancreatic B-cells, which release insulin How does insulin stimulate glucose uptake? Insulin stimulates GLUT4 transporters, which bring glucose to skeletal muscle and adipose tissue for storage In which tissues does insulin stimulate glucose uptake? Insulin regulates translocation of GLUT4 from intracellular compartment to the cell surface -glucose in small intestine anaerobically metabolized to lactate, rest sent to liver via portal vein -liver performs glycolysis and glycogenesis and fat conversion - non uptaken/metabolized glucose released into circulation -GLUT 2 transporters in pancreas stimulate insulin release -GLUT 1 and 3 in brain stimulate glycolysis -GLUT 4 in skeletal muscle and adipose tissue stimulated by insulin release --skeletal muscle performs glycolysis and glycogenesis --adipose tissue performs glycolysis and CHO conversion to fat Continue reading >>

Insulin

Insulin

Sort What happens in normal metabolism? a shift from carb to fat metabolism occurs within the body in between meals, when our blood glucose levels are low. Following a meal we enter an absorptive state in which ingested nutrients such as glucose enter the blood from the GI tract. During this absorptive state glucose is used by many tissues for energy metabolism. The high levels of glucose in the absorptive state stimulate the pancreas to release insulin, which lowers the blood glucose levels. Because of decreasing blood glucose levels, there is a shift in the tissue energy metabolism from cars to fatty acids, as the body enters the postabsorptive state, which occurs about four hours after a meal and continues until the next meal. Continue reading >>

A&p2 Chapter 17

A&p2 Chapter 17

Sort which of the following is a function of growth hormone check all that apply - GH promotes tissue growth -GH inhibits protein synthesis -GH targets many organs -GH stimulate milk secretion by the mammary glands -GH promotes tissue repair and maintenance throughout life GH promotes tissue growth GH targets many organs GH promotes tissue repair and maintenance throughout life which of the following is a function of ADH -increase urine volume output and cause blood vessel dilation -increase urine volume output and cause blood vessel constriction -decrease urine volume output and cause blood vessel constriction -decrease urine volume output, but has no effect on blood vessels decrease urine volume output and cause blood vessel constriction which of the following statements about thyroxine is true? -it is water-insoluble -it is lipophilic -it cannot pass through the cell membrane -the first and second choices are correct -all three choices are correct the first and second choices are correct the thyroid gland secretes large amounts of _____ and _____ -triiodothyronine; no tetraiodothyronine -tetraiodothyronine; small amounts of triiodothyronine -tetraiodothyronine; no triiodothyronine tetraiodothyronine; small amounts of triiodothyronine which of the following statements about thyroid hormones is true? -T3 and T4 both enter the target cells -only the T4 form can enter the nucleus -inside the target cell, all T3 is converted to T4 T3 and T4 both enter the target cells steroid hormones bind to _______ of the target cell - carbohydrate receptors on the cell membrane - protein receptors in the cytoplasm or nucleus - protein receptors on the cell membrane - carbohydrate receptors in the cytoplasm protein receptors in the cytoplasm or nucleus the steroid hormone receptor compl Continue reading >>

Metabolic Effects Of Insulin & Glucagon

Metabolic Effects Of Insulin & Glucagon

Sort 4 Major organs that play a dominant role in fuel metabolism ("LAMB") 1)Liver 2)Adipose 3)Muscle 4)Brain -- -->Each of the aforementioned contains a unique set of enzymes such that eaach organ is specialized for the storage, use, and generation of **specifice fuels** -->Communicate with each to provide substrates to antoher or process compounds produced by other organs -->Communication btwn tissues is mediated by the NS, by the availibility of CIRCULATING SUBSTRATES, & by variation in the levels of PLASMA HORMONES 2 Hormones that control the integration of energy metabolism 1)Insuln 2)Glucagon (***Catecholamines play a supporting role) -- -->Changes in the circulatin levels of insulin & glucagon allow the body to store energy when food is availible in ABUDANCE or to make stored energy available during **2 major situations** 1)Survival Crises (famine, severe injury) 2)Flight or Flight Situations Structure of Insulin -->See Slide #9 for details -- NOTE: -->Pig (porcine) AND Beef (bovine) insulin differ from human insulin at **1* and *3** amino acid positions, respectively 1)When used in humans for the treatment of DIABETES, *antibodies to these foreign proteins develop* -->Use of *human recombinant insulin has eliminated this problem* Features of Synthesis of Insulin -->Involves 2 inactive precusors (preproinsulin & proinsulin), which are sequentially cleaved to form the ACTIVE HORMONE + C-PEPTIDE -->Stored in the **cytosol in granules that are released via *exocytosis** --->Is degraded by *inuslinase** (found mostly in the LIVER, & the kidney [lesser extent] ) -->Has a **SHORT HALF LIFE*(plasma half-life of approx. 6 minutes* 1)Short duration of actions permits rapid changes in CIRCULATING LEVELS OF THE HORMONE Factors that stimulate insulin secretion 1)Glucose -->β Continue reading >>

Insulin's Effects On Metabolism

Insulin's Effects On Metabolism

Sort - vesicles carry multiple molecules of glucose transport proteins in their own membrane - transport proteins bind with the cell membrane and facilitate glucose uptake into the cells - when there is no more insulin available, the vesicles seperate from the cell membrane (within 3-5 mins) - then move back to the interior of the cell to be used again How do the intracellular vesicles operate to increase glucose transport? - blood glucose concentration begins to fall - insulin secreation decreases rapidly - liver glycogen is split back into glucose - glucose is released back into the blood - keeping the glucose concentration from falling too low What happens with insulin and glucose (all forms) inbetween meals when food is not available? - decrease secreation of insulin by pancreas - therefore, stops further synthesis of glycogen by the liver and prevents further uptake of glucose by liver -activates phosphorylase, causing the splitting of glycogen into glucose phosphate -activates glucose phosphatase, causing phosphate to split from glucose = free glucose in the blood After a meal, blood glucose begins to fall to a low level; what are the events that cause the liver to release glucose back into the circulation? - (mainly) by decreasing the quantities and activities of the liver enzymes required for gluconeogenesis - (partly) by decreasing the release of amino acids from muscle (and other extrahepatic tissues) - thereby decreasing the availability of necessary precursors required for gluconeogenesis How does insulin inhibit gluconeogenesis? - stimulates the transport of many amino acids into cells - increases the translation of mRNA, forming new proteins - stimulates protein synthesis, especially of enzymes - inhibits protein catabolism - inhibits gluconeogenesis in th Continue reading >>

Insulin Versus Glucagon/epinephrine

Insulin Versus Glucagon/epinephrine

it is produced by Beta-cells in the islets of Langerhans. This is produced by alpha-cells in the islets of Langerhans. Describe the metabolic relationship between insulin, glucagon and epinephrine. The metabolic effects of glucagon and epinephrine are similar to each other but opposite to that of insulin in that they RAISE the level of blood glucose. Describe the differences between the roles of glucagon and epinephrine Epinephrine has pronounced effects on heart rate, and blood pressure, whereas glucagon has much greater effects on liver and only epinephrine affects muscle cells. This is produced in the WELL FED STATE (glucose is plentiful in blood) and promotes the storage of energy and glucose. What is the molecular process with which insulin stimulates the storage of energy and glucose? It does this in part by stimulating protein phosphatase which removes phosphates from enzymes. Therefore, enzymes which are activated by insulin (phosphatase) will be in their non-phosphorylated form. Describe when glucagon and epinephrine are produced. Glucagon and epinephrine are secreted when the body is in the NEED STATE for either glucose or energy. They control enzymes through initiating a phosphorylation cascade and therefore enzymes stimulated by glucagon and epinephrine will be active in their phosphorylated state (using kinase, which phosphorylates things). If we are witnessing glucose uptake in muscle and adipose tissue, then what key metabolic hormone is being triggered? If we are witnessing glycolysis, then what key metabolic hormone is being triggered? Glycolysis- the conversion of glucose to pyruvate- INSULIN If we are witnessing glycogenesis, then what key metabolic hormone is being triggered? Glycogenesis- the production of glycogen from glucose- INSULIN If we are w Continue reading >>

Unit 3- Insulin And Glucagon

Unit 3- Insulin And Glucagon

Sort steps of biosynthesis of insulin in beta-cells 1. insulin gene expressed in nucleus of B-cells (insulin mRNA) 2. translation in cytosol, synthesis of N-terminal signal sequence directs complex to RER 3. signal sequence hydrophobic and directs to lumen of RER; preproinsulin is formed 4. in RER, preproinsulin is cleaved-->proinsulin and signal sequence; disulfide bridges between A and B chains are correctly aligned with help of PDI (protein disulfide isomerase) and a molecular chaperone protein 5. properly folded proinsulin -->cis-Golgi apparatus; cleaved into C-peptide and insulin 6. C-peptide and insulin stored in vesicles ready for secretion 7. upon arrival of signal, equimolar amounts of active insulin and C-peptide are released how beta cells detect blood glucose variations 1. glucose enters B-cells via GLUT-2 (insulin INDEPENDENT glucose transporter) *glucose transport exceeds rate of glucose utilization and is not limiting 2. glucose trapped in beta cells through phosphorylation to glucose-6-P catalyzed by glucokinase 3. G6P->glycolysis->TCA cycle->ETC to produce ATP *ATP/ADP ratio increases in cell with glucose concentration 4. elevated ratio inhibits ATP-sensitive potassium channel 5. accumulation of K+ in cytosol of B-cells = membrane depolarization 6. opening of a voltage-gated calcium channel = influx of calcium 7. increase in cytosolic calcium triggers regulated exocytosis of insulin in secretory vessels minor regulators of glucagon secretion -certain amino acids stimulate secretion *note: amino acids can stimulate both glucagon and insulin -Insulin and incretins (GLP-1) inhibit secretion Neural factors: -epinephrine- stimulates release of glucagon (regardless of glucose concentration) -neural input from CNS can stimulate secretion -cortisol and growth h Continue reading >>

17. Insulin Metabolism

17. Insulin Metabolism

Sort The concept of metabolic homeostasis and the factors that contribute to this process Is control of the balance between substrate need and substrate availability The inter-tissue integration required for metabolic homeostasis is achieved in several ways: 1. the concentration of nutrients or metabolites in the blood affects the rate at which they are used or stored in different tissues 2. Hormones carry messages to their individual target tissues about the physiologic demands of the body and the current level of nutrient supply or demand 3. The central nervous system uses neural signals to control tissue metabolism, either directly or through the release of hormones 4. Insulin and glucagon are the two major hormones that regulate fuel storage and metabolism The role of insulin and glucagon in metabolism Insulin: Is released in response to carbohydrate ingestion Promotes glucose utilization as fuel Promotes storage of glucose as glycogen and of excess glucose as fat Is the major anabolic hormone - increases protein synthesis and cell growth Glucagon: Is the major counterregulatory hormone of insulin Decreases in response to a carbohydrate meal Is elevated during fasting Promotes glucose production (glycogenolysis, gluconeogenesis) Stimulates the mobilization of fatty acids from adipose tissue DOES NOT affect skeletal muscle The processes involving the synthesis of insulin and glucagon Insulin made as a larger precursor called proinsulin in the beta cells of the islets of Langerhans Proinsulin cleaved into mature insulin and C-peptide, which is released into the blood In type I diabetes, the beta cells are destroyed by an autoimmune response and no insulin is made Glucagon is synthesized in the alpha cells of the islets of Langerhans in the pancreas Glucagon is also sy Continue reading >>

Insulin Flashcards | Quizlet

Insulin Flashcards | Quizlet

many biochemical processes that contribute to the breakdown, formation, and inter-conversion of carbohydrates in living organisms. hormone produced by beta cells of the pancreas which allows the body to use glucose from carbohydrates as fuel or store it for when it is needed such as physical activity or in between meals It helps keep blood sugar in check from being to high (hyperglycemia) When blood sugar rises, beta cells in the pancreas are signaled to release insulin into the system The insulin attaches to cells and signals for them to take in the glucose If there is more sugar than the body needs, insulin can also help store it in the liver which can be used when it is needed When glycogen is fully restored, insulin stimulates glycolysis to get rid of blood glucose which can be used to bump up some intermediates of the CAC even all the way down to the mitochondria, which can then make protein synthesis and fat metabolism easier The body can become resistant to or not produce enough insulin if blood sugar levels remain too high for too long (hyperglycemia) - insulin resistance is another hormone responsible for maintaining proper blood sugar levels Glucagon secretion can be inhibited by raised blood sugar levels or high carbohydrate meals Stimulates the liver to convert stored glycogen into glucose to be released into the bloodstream It is also produced in the pancreas but by the alpha cells The role of glucagon is to keep blood glucose levels from dropping too low Glucose uptake in muscle and adipose tissue The GLUT4 transporter is a insulin regulated transporter of glucose Insulin regulates the uptake of glucose into cells through this transporter Insulin stimulates the movement of the GLUT4 transporter to the surface of the cells to take in glucose Once glucose i Continue reading >>

More in diabetes