Christmas Biology Exam

Name: ______

  1. Scientific investigation usually begins with an observation which leads to a hypothesis. Describe the process of the scientific method from the point of devising a hypothesis: ______(12)
  1. List the five characteristics of life:

i.______(3)

ii.______(3)

iii.______(3)

iv.______(3)

v.______(3)

  1. Name the six elements present in food:

i.______(3)

ii.______(3)

iii.______(3)

iv.______(3)

v.______(3)

vi.______(3)

  1. Name the five elements present in the body as dissolved salts:

i.______(3)

ii.______(3)

iii.______(3)

iv.______(3)

v.______(3)

  1. Name the three types of carbohydrate and give one example of each type:

Type:

i.______(3)

ii.______(3)

iii.______(3)

Example:

i.______(3)

ii.______(3)

iii.______(3)

  1. In relation to vitamins, choose one fat-soluble and one water soluble, and name one function, onesource and one deficiency disease of each in the table below:

Name of vitamin / Function / Source / Deficiency disease
Fat-soluble vitamin
Water-soluble vitamin

(24 marks)

  1. State a function of the cell membrane: ______(3)
  1. State the function of ribosomes in cells: ______(3)
  1. What is the function of chloroplasts in plant cells? ______(3)
  1. State one feature that would allow you to identify an eukaryotic cell: ______(3)
  1. What is a prokaryotic cell? ______(3)
  1. What term is used to describe a cellular reaction in which large molecules are broken down into smaller ones? ______(3)
  1. What is a tissue? ______(3)
  1. Give one example of a plant tissue and describe it briefly: ______(6)
  1. Give one example of an animal tissue and describe it briefly: ______(6)
  1. What is an organ? ______(3)
  1. What is an enzyme? ______(3)
  1. List three factors that affect the rate of enzyme activity:

i.______(3)

ii.______(3)

iii.______(3)

  1. To which group of biomolecules do enzymes belong? ______(3)
  1. What is a denatured enzyme? ______(3)
  1. You carried out an experiment to investigate the effect of pH on the rate of enzyme action.

i.Name the enzyme you used: ______(3)

ii.Name the substrate you used: ______(3)

iii.How was the pH maintained at the required value? ______(3)

iv.State one factor that you kept constant in this experiment: ______(3)

v.How did you ensure that this factor was kept constant? ______(3)

vi.What was the desired result of this experiment? ______(6)

  1. What is the first stage process of respiration called? ______(3)
  1. In this first stage there is a release of ATP as glucose is converted to another substance.Name this other substance: ______(3)
  2. To what is the substance you have named in Q23 converted to under anaerobic conditions in:

i.Yeast? ______(3)

ii.A human muscle cell? ______(3)

  1. Under aerobic conditions the substance that you have named in Q23 is converted to an acetyl groupand in the process a small molecule is released.Name this small molecule: ______(3)
  1. The acetyl group now enters a cycle of reactions.What name is given to this cycle? ______(3)
  1. Where in the cell does this cycle take place? ______(3)
  1. How many ATP molecules does the metabolism of one glucose molecule yield under:

i.Anaerobic conditions? ______(3)

ii.Aerobic conditions? ______(3)

  1. State a use of each of the following in the biology laboratory:

i.Biuret test (copper sulphate and sodium hydroxide solutions): ______(3)

ii.Benedict’s test: ______(3)

  1. Define diffusion: ______(3)
  1. Define osmosis: ______(3)
  1. In an experiment, 10 cylinders of potato tissue were obtained using a cork borer. The cylinders were divided into two sets of five. Each set was dried on the outside by a standard technique, the total length measured and the total mass recorded. One set was immersed in tap water and the other set was immersed in a concentrated salt solution for 30 minutes and then the cylinders were remeasured. The results are shown below:

Group A (Tap water) / Group B (Salt solution)
Before immersion / 12.6 g
31.4 cm / 12.9 g
31.7 cm
After immersion / 13.2 g
31.9 cm / 11.3 g
31.1 cm

i.Describe the meaning of the results referring in your answer to osmosis, semi-permeable membrane, turgor, and plasmolysis.

______(12)