topic 5 - biological molecules and diet Flashcards
what are the biological molecules?
carbohydrates, lipids, proteins, nucleic acids
what is a monomer?
a building block that makes up a substance
examples of carbohydrates
bread, pasta, fruit, vegetables
what is the monomer of carbohydrates?
monosaccharide e.g. glucose
what is glucose used for?
used in cellular respiration to make ATP
what is the function of carbohydrates?
they are a fast source of energy
examples of lipids
fats, oils, butter
what is the monomer of lipids?
glycerol and fatty acids
what is the function of lipids?
they are a long term source of energy storage
examples of proteins?
beans, nuts, meat, eggs
what is the monomer of proteins?
amino acid
what is the function of proteins?
acting as enzymes, working in the immune system
what is the monomer of nucleic acid?
nucleotides
examples of nucleic acid?
DNA and RNA
chemical elements in carbohydrates?
Carbon
Hydrogen
Oxygen
chemical elements in lipids?
Carbon
Hydrogen
Oxygen
chemical elements in proteins?
Carbon
Hydrogen
Oxygen
Nitrogen
chemical elements in nucleic acid?
Carbon
Hydrogen
Oxygen
Nitrogen
Phosphorus
test for protein
- collect 5 food samples
- chop up first sample and put it in a test tube
- add 3cm of biuret solution
- shake or stir to mix the food and solution
- if the solution stays blue, there’s no protein. if it changes to purple, it contains protein
test for fat
- collect 5 food samples
- chop up first sample and put it in a test tube
- add enough ethanol to cover the food
- shake or stir to mix the food and ethanol
- put water in a different test tube
- pour ethanol (without food) into the new test tube
- if the water stays clear, there’s no fat. if it goes milky white, it contains fat
test for starch
- put food sample on a white tile
- add a few drops of iodine solution
- if it stays orangey-brown, it doesn’t contain starch. if it goes black-blue, it contains starch.
test for sugar
- put food sample in a boiling tube
- add 3cm of Benedict’s solution and mix with the food
- stand tube in a very hot water bath and leave for 5 minutes
- if it contains sugar, the solution will turn from blue to dirty green to yellow to orangey-red.
where is vitamin A found?
can be found in fruits, vegetables, dairy, fish, etc
where is vitamin C found?
fruits e.g. orange, lemon, tomato
where is vitamin D found?
fatty fish
what is the function of vitamin A?
important for normal vision, the immune system, reproduction, and growth and development
what is the function of vitamin C?
form blood vessels, cartilage, muscle and collagen in bones
what is the function of vitamin D?
help the body absorb and retain calcium and phosphorus
where is calcium found?
bones, teeth, starchy vegetables
where is iron found?
meat, seafood
what is the function of calcium?
build strong bones, help blood clotting
what is the function of iron?
make haemoglobin, boost immune system