MEH 2 - Intro To Metabolism Flashcards
What is meant by ‘transport work’ in cells?
Energy required for movement of ions and nutrients across membranes
What does ATP split into after it is used to provide energy?
ADP and Pi
What is the official SI unit of food energy?
Kilojoule
What is the general formula of a carbohydrate?
(CH2O)n
Put these in order of smallest to largest:
Oligosaccharides, disaccharides, monosaccharides, polysaccharides
- monosaccharides (single sugar units)
- disaccharides (2 units)
- oligosaccharides (3-12 units)
- polysaccharides (10-1000s units)
Give an example of a polysaccharide
Glycogen, starch, cellulose
Give some examples of dietary disaccharides
- sucrose (glucose-fructose)
- lactose (galactose-glucose)
- maltose (glucose-glucose)
True or false - starch is the main carbohydrate storage molecule in animals?
False - it’s the main storage molecule in plants. Glycogen is the main carbohydrate storage molecule in animals
What are the nine essential amino acids that cannot be synthesised by the body and must be obtained from other sources?
(Remember the mnemonic: ‘if learned this huge list may prove truly valuable’)
- isoleucine
- lysine
- threonine
- histidine
- leucine
- methionine
- phenylalanine
- tryptophan
- valine
What is fat composed of?
Lipids composed of triacylglycerols (3 fatty acids esterified to one glycerol)
Which vitamins are fat-soluble?
Vitamins A, D, E and K
Sodium, potassium and chloride are electrolytes. What are these required for?
They establish ion gradients across membranes, and maintain water balance
What is the routine maintenance amount of water that should be given through IV fluids?
30 ml/kg/day
Give some examples of dietary fibre
- cellulose
- lignin
- pectins
- gums
Why can humans not digest cellulose?
We do not make the required enzymes to break the beta-1,4 linkages in cellulose
What is the recommended average intake of dietary fibre?
18g/day
What are the consequences of a low fibre intake?
Constipation and bowel cancer
What are the benefits of a high fibre intake?
Lowers cholesterol and risk of diabetes
What are dietary reference values?
A series of estimates of the amount of energy and nutrients needed by different groups of healthy UK population
Which factors determine nutrient requirements?
Age, gender and level of physical activity
What is daily energy expenditure the sum of?
- basal metabolic rate
- diet-induced thermogenesis (energy required to process food)
- physical activity level
Give some factors that affect basal metabolic rate (the value that maintains resting activities of the body)
- body size
- gender
- environmental temperature
- endocrine status
- body temperature
What is obesity?
Excessive fat accumulation in adipose tissue which impairs health
How is BMI calculated?
Weight (kg) / height squared (metres squared)
