Biology -chemical composition of cells?

Question

given an unknown substance, how do i determine ( describe) if it contained, starch, sugar, protein, or lipids?

thankyou

Answer 1

there's a number of tests, especially a couple of famous ones. Basically what you would do is run these tests and see which ones come up positive nad which ones negative, and then just narrow it down. The common tests are:

Benedict's Solution: tests for reducing sugars (such as glucose)
Lugol's Iodine: tests for starch (the famous turn the potato black test)
Biuret Test: tests for presence of proteins
Sudan IV: tests for the presence of lipids

google or wikipedia these to find out how they're made and how they're run. These will pretty much work for every common substance.