Carbohydrates, lipids, proteins and nucleic acids
Answers are for parents and teachers.
1
Make a table comparing carbohydrates and lipids (groups, solubility, three functions).
Carbohydrates – mono-, di-, polysaccharides; mono- and disaccharides dissolve in water; energy, structure, reserve. Lipids – fats, waxes, phospholipids, steroids; insoluble in water; energy, membranes, heat insulation.
2
Write the four structural levels of a protein in order and give one example for each.
Primary – amino acid sequence (insulin); secondary – helix (keratin, collagen); tertiary – globule (myoglobin, enzymes); quaternary – several subunits (haemoglobin).
3
DNA contains 18% guanine. Find the percentages of the other three bases. Give cytosine first, then adenine; explain.
Cytosine 18% (G = C); adenine and thymine: (100 – 36) : 2 = 32% each.
4
Explain in 3–4 sentences the structure of ATP and how it releases energy in the cell.
ATP consists of adenine, ribose and three phosphate groups. When the last phosphate group is split off, ADP forms and about 40 kJ/mol of energy is released; this energy is used for cell processes.
5
Which disaccharide is broken down when most people drink milk and into which monosaccharides?
Lactose; into glucose and galactose.