Lecture 10 --energy nutrition: metabolism of CHO & Fats Flashcards
Carbohydrates (‘describe the molecules from which we derive energy’)
Formula: CH2O
Only MONOSACCHARIDES are absorbed
Proteins (‘describe the molecules from which we derive energy’)
Chains of amino acids joined by peptide bonds
Fats (‘describe the molecules from which we derive energy’)
Formula: CH3–(CH2)n–COOH
We mostly consume Triglycerides
Can be SATURATED or UNSATURATED
How much energy is in carbohydrates?
4 kcal/g
What are SATURATED FATS?
Have only linear, single bonds
What are UNSATURATED FATS?
have CIS DOUBLE BONDS (which give them ‘kinky chains’)
What form of Fatty Acid is easiest to metabolise? Why?
Saturated FA are easier to metabolise
Unsaturated FA have CIS DOUBLE BONDS which gives them ‘kinky chains’ that are hard to metabolise
What is the purpose of enzymes in Unsaturated FA metabolism?
To convert the CIS double bonds to TRANS double bonds
What are the enzymes involved in unsaturated FA metabolism?
(1) Enoyl CoA isomerase
(2) 2,4 Dienoyl CoA reductase
(‘Outline hepatic processing’) What are the 3 processes involved in hepatic processing?
(1) Glycogenesis
(2) Glycogenolysis
(3) Gluconeogenesis
What is GLYCOGENESIS
Conversion of glucose –> glycogen for storage
What is GLYCOGENOLYSIS
Breakdown of glycogen to glucose-6-phosphate
What is GLUCONEOGENESIS
Synthesis of glucose from Fats and Amino Acids (Alanine & Lactate)
What are the main Amino Acids used in gluconeogenesis?
Alanine
Lactate
What % of the liver = glycogen?
7-10% of weight of liver = glycogen