Food and nutrition Flashcards
what 7 components make up a balanced diet
carbohydrates - energy source proteins - growth and repair of muscle fats - energy source and waterproofs cell membrane vitamins - improves sight minerals - essential to bodes function water - solvent fibre - bulk for gut to push against
how do you measure BMI
weight/height(squared)
what health issues are associated with obesity
cancer cardiovascular desise type 2 diabetes gallstones hypertension (high BP)
what is coronary heart desise
when fatty acids are deposited in the coronary arteries restricting blood flow to heart muscles
how does excess salt affect blood
decreases water potential in blood so blood holds more water in blood - increasing blood pressure - hypertension - and damaging arteries
what things are unsaturated and saturated fats
animal fats - saturated
plant oils - unsaturated
where is cholesterol found
in cell membrane and skin
how is cholesterol transported around body
insoluble in water so converted to lipoproteins
what are HDL and what are they are made of
high density lipoproteins - unsaturated fats, cholesterol and proteins
what do HDL do
they carry cholesterol form body tissue to liver where it binds to cell surface membrane of receptor site
how is cholesterol used in the liver
used in cell metabolism to make bille or is just broken down
How is atherosclerosis affected by HDL
reduces deposition in artery walls
How is LDL different to HDL
made of saturated fats
transports cholesterol from liver to body tissue
causes deposition in artery walls
what decreases activity of LDL receptors
saturated fats - so more remains in blood and deposited in walls
what increases activity of LDL sites - reducing atheroclerosis
poly/mono unsaturated fats
how can you improve food production in plants
growth rate of crop size of yield from each plant reduces loss due to pests standardise plant size - harvest more easily improve response to fertilisers
how can you improve food production in animals
rate of growth
increse productivity
resistance to desise
what is artificial slection
the breeding of animals with desireble traits
what are 3 stages to selective breeding
isolation
artificial selection
inbrreding/line breeding
what is marker assisted selection
section of DNA used as marker to identify do sired characteristic and offspring are checked for this
how do microorganisms gain nutrition
digesting organic matter around them - leaving behind waste products
give example of fungi that grows on bread
pecicillum and mucor
how do micro-organism make bred taste sweat
microrganisma relese enzymes into food which breaks down carbohydrates releasing sugers
what is botulism
clostridum botulinum produces toxin botulin which causes botulism - toxic
