Nutrition, Diet & Body Weight Flashcards
Define catabolism.
Define anabolism.
- breakdown of molecules to release energy in the form of reducing power
- using energy to synthesise larger molecules for growth & maintenance
Define energy
What do we need energy for?
What type of energy do cells use?
- the capacity to do work
- biosynthetic,transport,mechanical & electrical work
- cells use chemical bond energy
How is ATP broken down?
What is this energy used for?
- energy released during phosphorylation of the bond in ATP
- ion transport, muscle contraction, biosynthesis, detoxification
What is the standard (SI) unit of food energy?
1 calorie= ?
1 kcal= ?kJ
- standard unit of food energy is the kJ
- 1 calorie actually means 1000 calories as ‘1 calorie’ is 1 kilocalorie
- 1kcal= 4.2kJ
What’s the general formula of a carbohydrate?
Define mono-, di-, oligo-, poly-sacchirides.
-(CH2O)n
-mono=single unit (glucose,galactose,fructose)
-di=2 units (maltose,sucrose,lactose)
-oligo=3-12 units (dextrin)
-poly=10-1000 units (glycogen,starch,
cellulose)
How many different amino acids are used in the body?
How many of these are essential & what does this mean?
- 20 used in the body
- 9 are essential, cannot be synthesised & must be obtained from diet
Name the 9 essential amino acids.
Isoleucine (if) Lysine (learned) Threonine (this) Histidine (huge) Leucine (list) Methionine (may) Phenylalanine (prove) Tryptophan (truly) Valine (valuable)
What is the difference in quality between plant & animal protein?
- animal protein= high quality, contains all 9 essential aa’s
- plant protein= low quality, usually deficient in one or more of the essential amino acids so must get protein from a variety of plants
What are lipids composed of?
What are their uses?
- triacylglycerols(3 fatty acids & 1 glycerol)
- have less O2 so yield more energy than carbs or protein
- needed for absorption of fat soluble vitamins (A,D,E,K)
What are minerals used for?
Give some examples.
- electrolytes establish ion gradients & maintain water balance
- calcium + phosphorus needed for structure (bones+teeth)
- Ca2+ also important for signalling
- iron needed for Hb
- enzyme co factors: Fe, Mg, Co, Cu
What are the routine maintenance values (IV fluid) of
- Na+,K+,Cl-
- water
- Na+,K+,Cl- is 1mmol/kg/day
- water is 30ml/kg/day
What are vitamins needed for?
- essential for life
- fat + water soluble (depends)
- deficiency will develop is intake inadequate
Why is dietary fibre important?
What’s the recommended average intake?
- not broken down but helps hold together & build mass to faeces
- prevents constipation & bowel cancer
- High fibre= reduce cholesterol
- 18g/day
What makes up our daily energy expenditure?
-basal metabolic rate (resting activities of the body e.g. function of organs, ion transport, biochemical reactions), diet induced thermogenesis (energy needed to break down food) & physical active level.
What are the energy stores of the human body?
- energy rich molecules of muscle= v short term
- carbohydrate store= mins or hrs depending on activity
- adipose= long term (40 days worth)
