Metabolism and Nutrition Flashcards
What is the metabolism of alcohol?
Alcohol -> Acetaldehyde -> acetate
Why is acetaldehyde buildup toxic?
It is a toxic intermediate which leads to greater susceptibility to intoxication
What enzyme catalyses alcohol metabolism?
Alcohol dehydrogenase
How does alcohol affect the body?
How much energy is produced by alcohol?
7kcal/kg
How much energy is produced by fat?
9kcal/kg
How much energy is produced by carbohydrates?
4kcal/kg
How much energy is produced by protein?
4kcal/kg
How much energy is stored as glycogen in the body?
150g in the liver, 300g in the muscles
How much energy is produced by fat?
9kcal/kg
How much energy is stored by fat?
90g/900kcal
How much energy is stored as carbohydrates?
1120kcal/260g
What are the four main macronutrients?
Protein, fat, carbohydrates and nucleic acid
What is the role of macronutrients?
Carbon source for repair and growth
What are micronutrients?
chemical substance required in trace amounts
What is the role of micronutrients?
Support cell and tissue function, and support metabolism
What is DRV?
Estimate of the recommended energy and nutrient requirements for the population
Which factors would affect the DRV?
Age, sex, height, weight, diseases, puberty, menstruation, pregnancy
What is the total kcal required?
23340 kcal
What is the DRV’s main carb source?
65% starch
What is the order of carb intake in the DRV?
65% starch, 25% sucrose, 6% lactose, 3% fructose, 3% glucose and 0.5% glycogen
What is the order of fat intake in the DRV?
94% triglycerides, 4% phospholipids, 1% cholesterol
What is the proportion of saturated and unsaturated fat?
70g/ 20g
How much energy is stored as protein?
50g
How much energy is stored as fibre?
30g
How much energy is stored as salt?
Less than 6g
What is the role of vitamin A?
vision and antioxidant against free radicals from drugs, smoking and UV radiation
What is the role of vitamin K?
Blood clotting
What is the role of vitamin D?
Bone health
What is the role of vitamin E?
Fertility and antioxidant
What is the role of vitamin B1?
Metabolism
What is the role of Riboflavin, Niacin and Pantothenic acid?
It is B2, B3 and B5 resposnible for metabolism
What is the role of vitamin B6 Pyridoxine?
Haemoglobin synthesis
What is the role of folate?
Prescribed in pregnancy for DNA synthesis for development
What is the role of colambin B12?
Haemoglobin synthesis
What is the role of calcium?
Bone health
What is the role of iodine?
Thyroid function
What is the role of iron?
Haemopoetisis and function of red blood cells
What is the role of sodium?
Osmotic balance
What is the implication of fat deficiency?
Deficiency of fat-soluble Vitamin A, D and E. Vitamin E deficiency is the clear marker of issues with fat deficiency/absorption. Fat is a source of essential fatty acids for inflammation mediator production and wound healing.
What is the implication of protein deficiency?
Brittle bones, thin hair, weak nails
What is the implication of carb deficiency?
Fatigue, headaches, bad breath
What is the implication of sodium deficiency?
Muscle cramping
What is metabolism and subtypes?
Sum of all reactions in the body. Catabolism is the breakdown of large molecules and anabolism is the breakdown of small molecules.
How long can glucose be used as a sole energy source?
30 mins
How long can glycogen be used as a sole energy source?
18h
How long can protein be used as a sole energy source?
21 days
How long can trialglycerol be used as a sole energy source?
Which molecules cannot be stored in the body?
Protein and alcohol
What is order of fruit and veg intake?
Elderly, women, men and children
Which cells do not progress onto the link reaction?
Red blood cells, medulla of kidney, Eye lens cells, Cells at injury sites, Tumour cells
Which 6 amino acids can undergo deamination?
alanine, cystein, seurine, glycine, threonine and hypotrophane
When does ketogenesis occur?
During starvation to provide brain with source of energy via soluble ketone bodies from high rates fatty acid oxidation. Occurs also when there is a high amount of acetyl coA entering Krebs
What is the function of the pentose phosphate pathway?
Synthesis of NADP
Why is the pentose phosphate pathway important for fatty acid?
NADPH is an important enzyme used for beta oxidation and fatty acid synthesis.
What is ATP?
Unit of energy transfer
What is BMR?
Energy needed to survive 24kcal/kg
Which factors increase BMR?
Pregnancy, overweight, low temperature and exercise
Which factors decrease BMR?
Starvation, age, high temperature and low activity
What is the rate limiting enzyme in fatty acid oxidation?
cartinine transferase
What is the rate limiting enzyme in fatty acid synthesis?
malonoyl coA synthase
What happens in the fed state?
Excess glucose transported by VLDL to be converted into fat sores, amino acids converted into proteins in liver, glucose stored as glycogen
What happens in the absorptive state?
Adipose stores undergo lipolysis, glycogenolysis, proteolysis of proteins into amino acids which undergo deamination, fatty acid oxidation
What happens in the starvation state?
Ketogenesis of acetyl coA –> acetoacetate/acetone/B-hydroxybutylcoA