DIAGNOSTIC TEST

CYCLES IN NATURE

Multiple Choice Questions

  1. The reusing of certain elements and compounds in nature is:

A. a recycle

B. a cycle

C. an ecosystem

  1. The process whereby plants lose water through their leaves is:

A. perspiration

B. transpiration

C. wilting

  1. The scientific term describing rain and snow is:

A. rainfall

B. precipitation

C. condensation

  1. Compounds containing carbon are called:

A. organic

B. carbonic

C. oxygenated

  1. The process that converts carbon dioxide and water to sugar and oxygen is:

A. respiration

B. breathing

C. photosynthesis

  1. The process that converts sugar and oxygen into carbon dioxide and water is:

A. transpiration

B. respiration

C. photosynthesis

  1. The bacteria found on legume roots that converts atmospheric nitrogen to a form useable by plants are:

A. nitrogen-fixing bacteria

B. denitrifying bacteria

C. putrefactive bacteria

  1. Another way that atmospheric nitrogen can be solidified or ‘fixed’ into a more solid form is by:

A. denitrifying bacteria

B. pea and bean leaves

C. lightning

  1. The nitrogenous wastes produced by animals include:

A. urea, uric acid and ammonia

B. atmospheric nitrogen

C. faeces

  1. The process of burning is:

A. decomposition

B. combustion

C. respiration

True-False Questions

  1. The formula for carbon dioxide is CO2.
  2. The only compounds that cycle in nature are water and carbon.
  3. Nitrogen in animals is mainly in the forms of amino acids and proteins.
  4. Human urine contains nitrogen-containing wastes of urea and uric acid.
  5. The 2 processes, respiration and photosynthesis, are exactly opposite reactions.

Short Answer Questions

  1. State the Law of Conservation of Matter.
  2. Name 3 processes that convert carbon within organic compounds in animals back to atmospheric carbon dioxide.
  3. Why is it true to say that some of the carbon atoms that made up the famous inventor and painter, Leonardo da Vinci, might be inside your body right now?
  4. Name 3 organic compounds needed by living things.
  5. Why is the phosphorus cycle different from other element cycles?

DIAGNOSTIC TEST

CYCLES IN NATURE

ANSWERS

1.B 2.B 3.B 4.A 5.C 6.B 7.A 8.C 9.A 10.B

11.T 12.F 13.T 14.T 15.F

  1. Matter cannot be created nor destroyed in any chemical reaction. It can only changed from one form to another.
  2. Respiration, combustion by burning the dead animals, decomposition from the respiration of the decomposing bacteria and fungi
  3. The number of carbon atoms on earth is always the same. They are found in different forms such as carbon dioxide and sugars. Hence, the carbon atoms from Leonardo da Vinci would have been respired or released on decomposition of his dead remains to form other forms that have recycled for centuries.
  4. Carbohydrates (sugars and starches), proteins, lipids (fats and oils)
  5. Phosphorus in the form of phosphates is deposited as bird faeces (guano) on land masses such as the Pacific island of Nauru. Rain then erodes the guano into the ocean. The phosphorus then erodes even further into the ocean but little is deposited back onto the land. Hence, it does recycle as effectively as water, carbon, oxygen and nitrogen.