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biology 0610printed 46 · PDF 46
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printed 46 · PDF 46
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Proteins
Contain 4 elements - carbon oxygen hydrogen and nitrogen. Some proteins also
contain Sulphur.
Proteins are made up of many amino acids joined together in long chains.
Proteins are needed for various things. They are needed to make enzymes and
antibodies.
Haemoglobin, the red pigment in mammalian blood, is a protein.
Hair and fingernails are also made from a protein called keratin.
Biuret reagent can be used to check the presence of proteins. If protein is present
color change from blue to violet is observed
DNA
Found in the nucleus of every cell (except for red blood cells).
Double-helix shape
Carries the instruction which tells the cell which amino acids to link together in which
sequence to make a particular gene
Inherited from parents
Made up of smaller molecules called nucleotides. Nucleotides are linked together to
form DNA.
Each nucleotide contains a base
There are 4 types of bases: “A,C,G,T”
A is for Adenine, C is for cytosine, G is for guanine and T is for thymine
“A” base always forms a bond with base “T” and base “C” always forms a bond with
base “G”. This is known as complementary base pairing.
For Vitamin C presence, the DCPIP test is carried out in which a DCPIP solution is
added to a solution. If it contains Vitamin C, it goes from blue to colorless