Absorptive and postabsorptive state of metabolism. Chapter 25: Absorptive and Postabsorptive States Flashcards 2022-10-17
Absorptive and postabsorptive state of metabolism
The human body is constantly undergoing metabolic processes to sustain life and maintain homeostasis. These processes can be divided into two main states: the absorptive state and the postabsorptive state.
The absorptive state, also known as the fed state, occurs when the body is actively digesting and absorbing nutrients from food. This typically occurs after a meal has been consumed and can last for several hours. During the absorptive state, the body's main energy source is glucose, which is derived from the breakdown of carbohydrates in the diet. Glucose is used by cells throughout the body to produce energy and support various physiological processes.
In contrast, the postabsorptive state, also known as the fasting state, occurs when the body is not actively digesting and absorbing nutrients. This typically occurs between meals or during periods of extended fasting. During the postabsorptive state, the body's main energy source shifts from glucose to fat. The liver breaks down stored glycogen into glucose, which is then released into the bloodstream to be used by cells as an energy source. If glycogen stores become depleted, the body begins to break down fats from fat cells and convert them into molecules called ketones, which can also be used by cells as an energy source.
The absorptive and postabsorptive states have important implications for energy metabolism and overall health. In the absorptive state, the body is able to easily obtain energy from the diet, which can be used to support various physiological processes. However, if the body is constantly in the absorptive state and consuming more calories than it needs, it can lead to weight gain and other negative health outcomes. On the other hand, the postabsorptive state can be beneficial for weight loss and improving overall health, as it forces the body to rely on stored energy sources rather than constantly consuming new nutrients.
In conclusion, the absorptive and postabsorptive states of metabolism refer to the body's use of nutrients and energy sources at different times. Understanding these states can help individuals make informed decisions about their diet and lifestyle to support optimal health.
Metabolic States of the Body · Anatomy and Physiology
Insulin stimulates the uptake of glucose into the cells. After ingestion of food, fats and proteins are processed as described previously; however, the glucose processing changes a bit. Other factors, such as hormones and neurotransmitters, potentiate or inhibit the effects of the blood nutrients on insulin secretion. Evidence has also been reported, which implicates environmental toxins. The absorptive state is the period during which ingested nutrients enter the blood and some of these nutrients supply the energy need of the body while the remainder is stored. Pyruvate, lactate, and alanine from muscle cells are not converted into acetyl CoA and used in the Krebs cycle, but are exported to the liver to be used in the synthesis of glucose.
Chapter 25: Absorptive and Postabsorptive States Flashcards
EXAMPLES Three to five hours after nursing, the baby wakes up ready to nurse again. Glycogen and triglyceride storage slows. When triglycerides and fatty acids are broken down, acetyl CoA is created. Amino acids and fats are used to form degraded protein, and small amounts are used to provide ATP. Glycogen and triglyceride storage slows.
24.5 Metabolic States of the Body
Parasympathetic fibers stimulate insulin secretion. There is evidence for a genetic predisposition, particularly to IDDM. In response to the decrease in glucose, insulin levels also drop. Depending on the amounts and types of nutrients ingested, the absorptive state can linger for up to 4 hours. Insulin also promotes the synthesis of protein in muscle. Our body initially relies on glycogen stores for glucose.
Absorptive and Postabsorptive States
As the postabsorptive state begins, glucose levels drop, and there is a corresponding drop in insulin levels. Muscle is quantitatively the most important tissue in this respect. If the fast is not broken and starvation begins to set in, during the initial days, glucose produced from gluconeogenesis is still used by the brain and organs. For example, muscles will switch from using glucose to fatty acids as fuel. At the start of exercising the energy the body gets quickly is from the anaerobic metabolism using mostly muscle glycogen.
24.5: Metabolic States of the Body
After these stores have been replenished, excess glucose that is absorbed by the liver will be converted into triglycerides and fatty acids for long-term storage. Its target is the liver tissue and its actions are opposed to that of insulin. This creation results from the conversion of acetyl CoA by thiolase into acetoacetyl CoA. Viruses that have been implicated are Coxsackie B virus, mumps and rubella. Voluntary muscle contractions are also used to produce heat. The liver, which normally absorbs and processes glucose, will not do so after a prolonged fast. Most amino acids enter cells and are used to synthesize proteins and any excess amino acids are converted to carbohydrate or fat.
Difference Between Absorptive and Postabsorptive State
Metabolites are transformed to fat if they are not used for anabolism. Overweight and obesity Overweight is a term to describe an increased amount of fat in the body and obesity is the state of being excessively overweight. The below infographic provides more comparisons related to the difference between absorptive and postabsorptive state. Glucagon acts upon the liver cells, where it inhibits the synthesis of glycogen and stimulates the breakdown of stored glycogen back into glucose. Provided by: Nutrition and Metabolism Journal. The main roles of insulin are to stimulate the movement of glucose from extracellular fluid into cells by facilitated diffusion, stimulate glycogen synthesis and inhibit glycogen catabolism.
THE ABSORPTIVE AND POST
The constituent parts of these carbohydrates, fats, and proteins are transported across the intestinal wall and enter the bloodstream sugars and amino acids or the lymphatic system fats. This glucose is released from the liver to be used by the peripheral tissues and the brain. Glucose consumption in the tissues and glucose production are balanced when the body is at rest. The ingestion of food and the rise of glucose concentrations in the bloodstream stimulate pancreatic beta cells to release insulin into the bloodstream, where it initiates the absorption of blood glucose by liver hepatocytes, and by adipose and muscle cells. Digestion begins the moment you put food into your mouth, as the food is broken down into its constituent parts to be absorbed through the intestine. Apart from the symptoms mentioned in the patient above listlessness, weight loss, polyuria, polydipsia, Kussmaul breathing , vomiting and abdominal discomfort, mental confusion and coma, and tachycardia and hypertension can also be present.
metabolsim during absorptive and postabsorptive states Flashcards
Absorptive and Postabsorptive States The absorptive state is the time during and right after eating a meal. Once inside these cells, glucose is immediately converted into glucose-6-phosphate. The doctor noticed that her breathing was rapid and shallow Kussmaul breathing , and that it smelled of acetone. Overall survival is dependent on the amount of fat and protein stored in the body. Blood Glucose Responses and Incidence of Hypoglycemia in Elite Tennis Players. Furthermore, during insulin and partial glucagon deficiency, and the exclusive partial deficiency of glucagon, the rate of glucose appearance increases to a point greater than the rate of glucose disappearance. During this state glucose is the most important energy fuel.
Regulation of Organic Metabolism, Growth and Energy Balance
Insulin has a central role in the control of metabolism. Once these stores are fully depleted, proteins from muscles are released and broken down for glucose synthesis. They undergo storage in tissues. Glucose is the main energy source in this state. After an oral glucose load it increases to reach a peak between 30 and 60 min and returns to normal by 2 h. It also stimulates the metabolic rate and therefore controls changes in energy expenditure. The Absorptive State The absorptive state, or the fed state, occurs after a meal when your body is digesting the food and absorbing the nutrients anabolism exceeds catabolism.