Module 2.1- Energy Metabolism Flashcards
Describe the difference between absorptive and post-absorptive phases of fuel metabolism. Define catabolism, anabolism and give examples of hormones involved with each of these. Define Basal Metabolic Rate (BMR)
What are the three kinds of fuels an animal body demands?
Amino Acids (protein), fatty acids (fats and acids) and glucose (carbohydrates)
Why do animal bodies require fuel?
For Homeostasis (the maintenance of the body) and because they are building blocks for growth and reproduction.
Is it likely that the supply of fuel matches the demand for it in an animals body?
Highly unlikely.
How does the animal body cope with the differences between supply and demand for fuels?
Energy (fuel) metabolism. The endocrine and homeostasis systems of the body assist in maintaining constant energy supply, dealing with excess and shortcomings in energy intake
Which body systems assist in maintaining the supply of energy needed by the body?
Endocrine and Homeostasis
What is anabolism?
Building up of tissues
What is catabolism?
Breaking down of tissues
What are the two steps of catabolism?
Hydrolysis of larger organic molecules (similar to what happens in the digestive tract) followed by oxidation of the smaller molecules to release energy for ATP production
What regulates metabolic function?
Substrate concentration
Enzyme activity
Enzyme concentration
Compartmentation (eg. glycolysis=cytosol, Krebs cycle=mitochondrial matrix)
Outline Carbohydrate (glucose) conversion as part of energy metabolism?
Carbohydrate compound is oxidised generating energy, CO2 and H2O and substrates for other metabolic reactions. Converted into Glycogen which can be readily stored and retrieved for conversion into ATP.
What is ATP?
adenosine triphosphate, the chemical compound which the body can use as energy.
What is Glycogen?
A product of the biochemical pathway of conversion of carbohydrate (glucose) into useable energy. Can be readily stored and retrieved.
How are Amino Acids transported in the body?
In the blood
What are Amino Acids used for?
Protein synthesis
Outline the chemical process of the conversion of Amino Acids to useable energy
Catabolised via Proteolysis
Amino acid (in blood) -> Protein (in cell, readily stored and retrieved in cell) -> CO2 + H2O + NH3 + energy (in cell)
2 NH3 then converted into urea in the liver.
How are Amino Acids stored in cells?
Converted via Proteolysis into proteins to be stored in the cell
Outline the chemical process of fat metabolism
Fats (triglycerides) broken down by lipoprotein lipase. Fatty acids are taken up by the liver (glycerol -> liver). Fatty acids are oxidised for energy + H2O + CO2.
Unused glycerol is combined with fatty acids and stored as fat droplets until they are ready to be released back into the blood
What happens when biomolecules exist in excess in the body?
They are stored as storage molecules (glycogen, triglycerides)
What can biomolecules be used for?
Synthesis of other molecules
What is released when molecules are broken down?
Energy is released
What is metabolic rate?
The rate at which energy is expended during internal and external work.
What is energy balance?
Energy input - energy output (heat + work)
What are some things that cause an animal to have a higher energy output than usual?
Growth, reproduction, lactation