B4 & B7.1 - biological molecules, Human diet Flashcards
elements that make up carbohydrates, lipids, protein
carbohydrates- carbon, hydrogen, oxygen
lipids- carbon, hydrogen, oxygen
protein- carbon, hydrogen, oxygen, nitrogen
4 food sources for carbohydrates, lipids, protein
carbohydrates- meat, fish, cheese, beans
lipids- rice, potato, pasta, bread
protein- red meat, egg yolk, soy beans, chociiolate
importance of carbohydrates
-easy available energy released during respiration
-excess stored as glycogen in liver and muscles
-if not used, converted into fat
- 16 KJ/g
importance of lipids
-insulation
-long term energy store
-organ protection
-sex hormone production
-buoyancy
- 39 KJ/g
what are monosaccharides, and eg
simple sugars, glucose, glycogen
importance of protein
-growth
-tissue repair
-making enzymes
-emergency energy
- 17 KJ/g
define disaccharides, and eg
2 simple sugars, maltose sugar
define polysaccharides, and eg
multiple sugar molecules bonded together, starch
what are basic units of carbohydrates
simple sugars
-say glucose in exam
in what form is sugars transported in humans and plants
plants - sucrose
humans - glucose
2 main groups of carbohydrates
-polysaccharides
-sugars (disaccharides, monosaccharides)
how does starch go to glucose
-starch broken down by Amylase into maltose
-maltose broken down by Maltase into glucose
are carbohydrates soluble
simple sugars - soluble
polysaccharides - insoluble
what do you call a fat molecule
triglyceride
what is triglyceride broken down into
3 fatty acids and glycerol
what breaks down triglyceride
lipase
are lipids soluble
no
define protein molecules
a long chain of amino acids
how does protein go to amino acids
-protein is broken down by protease into polypeptides
-polypeptides are broken down by peptidase into amino acids
what happens to amino acids
arranged in sequence depending on the DNA
are proteins soluble
some are
what do you use to test for starch
iodine reagent
what do you use to test for reducing sugar
benedicts reagent
what do you use to test for lipids
ethanol emulsion
what is the test for lipids called
emulsion test
what do you use to test for protein
biuret reagent
what is the colour of iodine reagent before the starch experiment
orangey brown
what is the colour of benedict reagent before the reducing sugars experiment
blue
what is the colour of ethanol reagent before the fats experiment
colourless
what is the colour of biuret reagent before the protein experiment
blue
what is the colour of iodine reagent for positive starch
blue- black
what is the colour of benedicts reagent for positive reducing sugars
-green (trace)
-yellow (low)
-orange (moderate)
-brick red (high)
what is the colour of ethanol reagent for positive fats
cloudy white emulsion
what is the colour of biuret reagent for positive protein
purple
What must you do as a safety procedure to when doing experiment for starch, reducing sugars, lipids and protein
-wear googles
-try to prevent direct contact with skin- wash immediately if it does
-Ethanol is flammable so keep away form naked fire
steps to test for starch
1-put googles
2 -add a few drops of iodine in the well of the spotting tile
3 -check for colour change-
orangey brown or blue- black