基础代谢率影响能量代谢的因素
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The storage of fat in the body is much greater than that of glucose
Alternative energy source
1g of fat contains 9 kcal
Energy sources
Proteins
The amount of energy provided by proteins is relatively small in human being
Metabolic pathways of the absorptive state
Summary of metabolism during the absorptive state
1. Energy is provided primarily by absorbed carbohydrate in a typical meal.
Growth, repair, and physical activity…...
ATP: “Energy Currency”
ATP is generated by combustion of carbohydrates, fats and proteins.
Adenine
Ribose
Energy sources
Catabolism and Anabolism
Catabolism: breaks down large molecules (such as polysaccharides, lipids, nucleic acids and proteins) into smaller units, releasing energy into smaller units (such as monosaccharides, fatty acids, nucleotides, and amino acids).
A type of lipid does not serve as a metabolic energy source.
A component of plasma membrane, bile salts, steroid hormones, etc.
Cholesterol Triglyceride
The breakdown of organic molecules liberates the enerຫໍສະໝຸດ Baiduy and ATP synthesis.
The breakdown of ATP serves as the immediate energy source for biological work.
Part I Energy metabolism
Definition
The metabolic processes by which energy is made available for the use of the body
The main sources of chemical energy are carbohydrates, fats, and protein.
Carbohydrates - mainly glucose
Major source: >70 % of the total energy ATP is produced
By glycolysis (oxygen independent ) By citric acid cycle ( Krebs cycle requires oxidation )
There is synthesis of body protein, but some of the amino acids in dietary protein are used for energy or converted to fat.
Metabolic pathways of the postabsorptive state
1g of protein contains 4 kcal
Protein will become the major energy source to maintain the essential vital activities in special conditions
Cholesterol
There is net uptake of glucose by the liver.
Some carbohydrate is stored as glycogen in liver and muscle, but most carbohydrates and fats in excess of that used for energy are stored as fat in adipose tissue.
1g of glucose contains 4 kcal Glucose is stored as glycogen in the liver and the
muscle
Energy sources
Fat – fatty acids
Major form of energy storage
Two states body provides energy
Absorptive state: ingested nutrients enter the blood from the gastrointestinal tract.
Postabsorptive state: gastrointestinal tract is empty of nutrients and the body’s own stores must supply energy.
Anabolism: construct molecules from smaller units, requiring energy.
Anabolism is powered by catabolism (hydrolysis of adenosine triphosphate (ATP)).
Alternative energy source
1g of fat contains 9 kcal
Energy sources
Proteins
The amount of energy provided by proteins is relatively small in human being
Metabolic pathways of the absorptive state
Summary of metabolism during the absorptive state
1. Energy is provided primarily by absorbed carbohydrate in a typical meal.
Growth, repair, and physical activity…...
ATP: “Energy Currency”
ATP is generated by combustion of carbohydrates, fats and proteins.
Adenine
Ribose
Energy sources
Catabolism and Anabolism
Catabolism: breaks down large molecules (such as polysaccharides, lipids, nucleic acids and proteins) into smaller units, releasing energy into smaller units (such as monosaccharides, fatty acids, nucleotides, and amino acids).
A type of lipid does not serve as a metabolic energy source.
A component of plasma membrane, bile salts, steroid hormones, etc.
Cholesterol Triglyceride
The breakdown of organic molecules liberates the enerຫໍສະໝຸດ Baiduy and ATP synthesis.
The breakdown of ATP serves as the immediate energy source for biological work.
Part I Energy metabolism
Definition
The metabolic processes by which energy is made available for the use of the body
The main sources of chemical energy are carbohydrates, fats, and protein.
Carbohydrates - mainly glucose
Major source: >70 % of the total energy ATP is produced
By glycolysis (oxygen independent ) By citric acid cycle ( Krebs cycle requires oxidation )
There is synthesis of body protein, but some of the amino acids in dietary protein are used for energy or converted to fat.
Metabolic pathways of the postabsorptive state
1g of protein contains 4 kcal
Protein will become the major energy source to maintain the essential vital activities in special conditions
Cholesterol
There is net uptake of glucose by the liver.
Some carbohydrate is stored as glycogen in liver and muscle, but most carbohydrates and fats in excess of that used for energy are stored as fat in adipose tissue.
1g of glucose contains 4 kcal Glucose is stored as glycogen in the liver and the
muscle
Energy sources
Fat – fatty acids
Major form of energy storage
Two states body provides energy
Absorptive state: ingested nutrients enter the blood from the gastrointestinal tract.
Postabsorptive state: gastrointestinal tract is empty of nutrients and the body’s own stores must supply energy.
Anabolism: construct molecules from smaller units, requiring energy.
Anabolism is powered by catabolism (hydrolysis of adenosine triphosphate (ATP)).