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A Handbook of Biology

Nitrogen

base

+

Sugar

+

Phosphate

=

Nucleotide

Adenine

+

Sugar

+

Phosphate

=

Adenylic

acid

Guanine

+

Sugar

+

Phosphate

=

Guanylic

acid

Cytosine

+

Sugar

+

Phosphate

=

Cytidylic

acid

Thymine

+

Sugar

+

Phosphate

=

Thymidylic

acid

Uracil

+

Sugar

+

Phosphate

=

Uridylic acid

Nucleic acids (DNA & RNA) are made up of nucleotides and function

as genetic material.

OH

OH

Adenine

O

OCH2

P

HO

OH

O

Adenylic a cid

Biomolecules having molecular weight greater than 1000 Da include

Proteins

Polysaccharides

Nucleic acids

Molecular weight is in the range of 10,000 Da

and above.

Acid insoluble fraction (macromolecular fraction) includes macromolecules

from cytoplasm and organelles.

Lipid is not strictly a macromolecule as its molecular weight does not exceed

800 Da. But it comes under acid insoluble fraction because many lipids are

arranged into structures like cell membranes. When a tissue is grinded, cell

membranes are broken and form water insoluble vesicles. They cannot be

filtered along acid soluble fraction.