Self-assessment questions 2.01
2 The chemicals of living cells
1 Apart from food, what other substances do cells need to take in?
2 Water has a high capacity for heat (thermal capacity). This is an advantage in living cells because …. (Select one of the following statements)
(a) any rise in temperature is small in comparison with the amount of heat absorbed by a cell
(b) any rise in temperature is large in comparison with the amount of heat absorbed by a cell
(c) the 75% water in a cell does not retain a lot of heat
(d) any change in temperature will cause a cell to heat up or cool down quickly.
3 (a) Give three examples of cell structures which contain structural proteins.
(b) What is the other type of protein in a cell?
4 Name the chemical elements present in a protein.
5 What name is given to the sub-units which make up all proteins?
6 A protein molecule which is denatured, has
(a) split into smaller molecules
(b) changed its shape
(c) combined with another molecule
(d) been diluted..
7 What kind of substance is a lipid?
8 In a cell, where are lipids found?
9 (a) What are the two types of chemical compound which combine to form a lipid?
(b) What elements are present in a lipid?
10 (a) Name four examples of compounds which are classed as carbohydrate.
(b) What elements are present in carbohydrates?
11 Write the formula for glucose.
12 If represents a glucose molecule draw (a) a maltose molecule, (b) part of a starch molecule.
reactions. The reactions do not ….….the ….…. which can take part in further reactions.
substances, proteins, enzymes, catalysts, speed up, use up, slow down
14 Enzymes will usually react with only one substance. This can be explained by the 'lock
and key' theory. If this theory is correct, which of the following substances, represented
by P, Q, R and S would be acted on by enzyme A?