1.
Biofuels are carbon-neutral. What does this mean?
Correct Answer
B. It recycles the carbon content already in the atmospHere
Explanation
Check it out here: http://www2.hci.edu.sg/y11hci0149/Website/advantagesalgae.html#carbonneutral
2.
The growth cycle of algae is:
Correct Answer
C. 10 days
Explanation
Algae can be cultivated and harvested within 10 days.
Other types of biofuels, like corn, on the other hand may take weeks or even months to grow.
Check it out here: http://www2.hci.edu.sg/y11hci0149/Website/advantagesalgae.html#advantage4
3.
The oil yield from algae is high because:
Correct Answer
A. It has a lot of lipids
Explanation
Algae has a lot of lipids. In fact, pond algae (also known as pond scum), with the highest yield of all strains, has 60% of its weight being oil
Check it out here: http://www2.hci.edu.sg/y11hci0149/Website/advantagesalgae.html#advantage3
4.
Algae cannot be used as:
Correct Answer
C. Something for removing salt from seawater
Explanation
Algae cannot be used for removing salt from seawater because they do not have the ability to desalinate water. While algae can be used as a fertilizer, biomass, and food source, they do not possess the necessary mechanisms to remove salt from seawater.
5.
Why is Algae environmentally friendly?
Correct Answer
B. Yes, it is carbon neutral and may even reduce carbon impact by 70%
Explanation
Algae does produce carbon dioxide, but it is carbon neutral so algae is environmentally friendly
6.
Algae cannot be grown in:
Correct Answer
E. None of the above
Explanation
Algae can be grown virtually anywhere as long as there is water, carbon dioxide and sunlight.
This includes ponds and even seawater and wastewater. It can also be grown in photobioreactors (also known as PBRs).
7.
Harvesting is:
Correct Answer
C. Separating algae from its medium (water)
Explanation
Check it out on the site: http://www2.hci.edu.sg/y11hci0149/website/algae.html#harvesting
8.
Which of the following about closed pond systems is false?
Correct Answer
C. It is just as complex as an open pond system
Explanation
A closed pond is just a open pond closed off using a greenhouse. It also solves most of the problems that are being faced in a open pond, like allowing better control over the environment. However, it has a system more complex than a open pond with the addition of a greenhouse, but less than a photobioreactor.
Check it out here: http://www2.hci.edu.sg/y11hci0149/website/algae.html#cultivation
9.
The main reason why open ponds have to be shallow is because:
Correct Answer
B. It maximises sunlight taken in by the algae
Explanation
Open ponds need to be shallow in order to maximize sunlight taken in by the algae. Sunlight is essential for photosynthesis, the process by which algae convert sunlight into energy. By keeping the ponds shallow, more sunlight can penetrate the water and reach the algae, allowing them to photosynthesize and grow more efficiently. This maximization of sunlight helps to optimize the growth and productivity of the algae, making shallow open ponds the preferred choice for cultivating algae.
10.
Algae can be grown only in seawater.
Correct Answer
B. False
Explanation
Algae can be grown virtually anywhere as long as there is water, carbon dioxide and sunlight.
This includes ponds and even seawater and wastewater. It can also be grown in photobioreactors (also known as PBRs).
Check it out here: http://www2.hci.edu.sg/y11hci0149/Website/advantagesalgae.html#advantage1
11.
Algae has a yield close to that of peanuts.
Correct Answer
B. False
Explanation
Peanut has a yield of only 113 gallons of oil per acre per year. Algae on the other hand has close to 20 000 gallons per acre per year, more than a hundred times that the yield of peanut
Check it out here: http://www2.hci.edu.sg/y11hci0149/website/algae.html#other biofuel
12.
Which of these methods can be used to extract algae?
Correct Answer(s)
A. Oil press
B. Chemical solvent
D. Carbon dioxide as a solvent
Explanation
Apart from the three forms of extraction: Oil press, Chemical Solvent and Supercritical Fluid (CO2), there is still another type of extraction method - Ultrasonic assisted extraction
Check it out here: http://www2.hci.edu.sg/y11hci0149/website/algae.html#Extraction