SECTION A
Answer all questions
Total marks [55]
1. List the two ions that occur in the highest concentrations in seawater
(2)
2. With reference to the life cycle and suitable examples, differentiate holoplankton and
meroplankton.
(4)
How many ATP molecules are utilized and produced during the process of glycolysis of
one molecule of glucose?
(2)
With the aid of an appropriate schematic diagram and reference to the photic and
aphotic zone, briefly explain the concept of compensation depth in the pelagic zone of
the marine environment.
(5)
Why are certain angiosperms referred to as halophytes?
(2)
Name any four macronutrients and two micronutrients inthe marine ecosystem? (3)
What is the most common form of silicon in seawater?
(2)
What are Phycocolloids? Name any two Phycocolloids and their economic importance (4)
Using the Henrys’ gas law equation, calculate the molar concentration of nitrogen gas
in seawater under 1.5 atmospheric pressure? Given: Ky of nitrogen gas in water =
1639.34 mm Hg /(mol/L).
(4)
10. Name the major group of the microbial community responsible for aerobic ammonium
oxidation in the marine ecosystem.
(2)
11. What is the scientific name of the largest bacterium discovered off the Namibia marine
waters?
(2)
12. In a tabular form, outline the main differences between marine Coccolithophores and
Silicoflagellates?
(4)
13. What is the function of the protonephridia in marine flatworms?
(2)
14. What class of the Chrysophyta do the diatoms belong to?
(2)
15. Name the four classes of marine Platyhelminthes.
(2)
16. Highlight any two characteristics of marine cephalopods.
(2)