finals post lab questions and results Flashcards
what is the percentage yield
mass or recovered dna/ mass of strawberries x100
what is the purpose of adding homogenizing solution to the sample
by facilitating the release of dna in the cells
helps break to release their contents
what was the purpose of adding ice-cold ethanol
to precipitate the dna from the homogenizing solution
dna is soluble in water but not in alcohol
ethanol reduces the solubility of the dna
its cold so that it helps by slowing down the process
what is the chemical component of the dische reagent
diphenylamine - dissolve in acidic sol.
such as acetic acid or sulfuric acid
- to detect the presence of deoxyribose in the dna
which component of dna will result in a positive reaction to the dische test
deoxyribose sugar
= blue color when react with dische reagent
what are alkaloids
naturally occurring organic compounds that contain nitrogen atoms
heterocyclic ring
generally soluble in organic solvents
what is the role of flavonoids in plants
provide pigmentation to flowers for pollination
they act as antioxidant, protect against uv light and defending against pathogens
libermann-burchard test tests for
sterols and triterpenoids
kedde test tests for
cardiac glycosides
bate-smith and metcalf test tests for
flavonoids
ferric chloride tests for
phenolic compounds and tannins
froth test tests for
saponins
keller-killiani tests for
cardiac glycosides
dragendorff’s test tests for
alkaloids
borntrager’s test tests for
anthraquinones
