Biological molecules Flashcards
Carbohydrates and fats are made up of
carbon, hydrogen and oxygen.
Proteins are made up of
carbon, hydrogen, oxygen and nitrogen
Starch, glycogen, and cellulose are made from
glucose
Proteins are made from
amino acids
Fats and oils are made from
3 fatty acids and 1 glycerol.
starch test
take few drops of sample on a white tile, add a drop of iodine solution. observe the color change from orange- brown to blue black confirming the presence of starch
protein test
take a knwon volume of sample, add few drops of buirette solution. observe the color change
a) blue to lilac ( traces )
b) blue to purple ( low concentration )
c) blue to violet ( high concentration)
vitamin C test
add 1cm³ of DCPIP solution in a test tube, add small amount of sample. observe the color of blue color disappearing
Fat test (lipids)
take sample in a test tube, add ethanol until you get a clear solution. add few drops of distilled water. if the solution turns cloudy or milky confirms the presence of fats
reducing sugars ( glucose ) test
take a known volume of sample, add equal volume of benedicts solution, heat using a thermostatically controlled digital water bath at 80°C. observe the color change
a) blue to green ( traces )
b) blue to yellow ( low concentration)
c) blue to orange ( mild concentration)
d) blue to brick red ( high concentration)
Structure of DNA:
Two strands coiled together to form a double helix
Each strand contains chemicals called bases
Bonds between pairs of bases hold the strands together
The bases always pair up in the same way: A with T, and C with G