Biomolecules

Macromolecules are large biomolecules with molecular masses in the range of about ten thousand daltons and above. In living tissues, the main macromolecules are:
- Proteins
- Nucleic acids
- Polysaccharides

Lipids are not strictly macromolecules, though they appear in the acid-insoluble fraction because they are associated with membranes.

The tertiary structure of a protein is the way the long polypeptide chain is folded upon itself into a 3-dimensional shape, like a hollow woollen ball. This 3D structure is essential for the biological activity of many proteins.

This is an activity-based question. From the chapter, small molecular weight biomolecules include amino acids, sugars, fatty acids, glycerol, nucleotides, nucleosides and nitrogen bases. You can choose 10 such compounds, write their structures from a textbook or model kit, and then look up whether any industry isolates or manufactures them. The chapter itself states that scientists isolate and purify compounds from living tissues, and many secondary metabolites such as drugs, essential oils, pigments, rubber, gums and antibiotics are useful to human welfare. Buyers may include the pharmaceutical industry, food industry, cosmetic industry, perfume industry and research laboratories.

This is an activity-based question. The chapter gives examples of proteins with functions such as insulin (hormone), antibodies (fight infectious agents), trypsin (enzyme), collagen (structural protein), receptors, and GLUT-4. Therapeutic proteins include substances like insulin, antibodies, and enzymes used in treatment. Other applications of proteins can include medicines, diagnostics, cosmetics, and research. The textbook only directly mentions that proteins have many biological roles and that some are hormones, antibodies, receptors and enzymes.

A triglyceride is a lipid made of one glycerol molecule joined with three fatty acid molecules by ester bonds. The chapter says that many lipids have both glycerol and fatty acids, and when the fatty acids are esterified with glycerol, they form monoglycerides, diglycerides and triglycerides. So, a triglyceride contains:
- Glycerol as the backbone
- 3 fatty acids attached by esterification

These are also called fats and oils depending on their melting point.