1.
1. How much of the Earth's surface does coral reefs cover?
Correct Answer
A. Less than 1%
Explanation
Coral reefs cover less than 1% of the Earth's surface. This is due to the fact that coral reefs are found in specific areas of the ocean where conditions are suitable for their growth, such as warm waters and shallow depths. While they may be visually striking and diverse in marine life, coral reefs are relatively small in comparison to the vast expanse of the Earth's surface.
2.
2.How much of the marine fish species do they support?
Correct Answer
C. 25%
Explanation
Marine ecosystems support approximately 25% of the world's fish species. This means that a quarter of all fish species can be found in the oceans, highlighting the importance of marine habitats for biodiversity and the overall health of the planet. These ecosystems provide a wide range of habitats and resources that sustain a diverse array of fish species, making them crucial for the balance and sustainability of marine life.
3.
3.What is/are the benefit(s) of coral reefs?
Correct Answer
D. All of the above
Explanation
Coral reefs provide multiple benefits including protecting coastal areas from erosion, as they act as a barrier against waves and storms. Additionally, the porous limestone skeleton of coral reefs can be used as a material for human bone grafts. Furthermore, coral reefs have been found to have potential in the treatment of various diseases such as HIV, cardiovascular diseases, and ulcers. Therefore, all of the mentioned benefits are associated with coral reefs.
4.
Which of the following is NOT a major threat to coral reefs?
Correct Answer
C. Increased salinity
Explanation
Coral reefs thrive in saltwater environments with a specific salinity range. While changes in salinity can stress corals, the primary threats to coral reefs include ocean acidification, which disrupts coral growth, overfishing, which disrupts the ecological balance, and coral bleaching, which causes corals to expel their symbiotic algae and lose their color, leading to potential death.
5.
5.What is/are the threat(s) to coral reefs?
Correct Answer
D. All of the above
Explanation
The correct answer is "All of the above" because all three options listed - global climate change, destructive fishing methods, and pollution - are indeed threats to coral reefs. Global climate change leads to rising sea temperatures and ocean acidification, both of which can harm coral reefs. Destructive fishing methods, such as using dynamite or cyanide, can directly damage or destroy coral reefs. Pollution from activities such as sewage discharge, oil spills, and chemical runoff can also have detrimental effects on coral reefs. Therefore, all three options pose threats to coral reefs.
6.
6.How much money do coral reefs contribute?
Correct Answer
C. USD $375billion
Explanation
Coral reefs contribute USD $375 billion to the economy. This is because coral reefs provide numerous economic benefits such as tourism, fisheries, and coastal protection. They attract tourists who engage in activities like snorkeling and diving, generating revenue for local businesses. Coral reefs also support fish populations, which are a vital source of income for fishing communities. Additionally, reefs act as natural barriers, protecting coastlines from storms and erosion, which saves money on infrastructure repairs. Overall, the economic value of coral reefs is significant, making them crucial for both local communities and the global economy.
7.
7. How many people rely on coral reefs for their livelihoods and food.
Correct Answer
A. 500million
Explanation
Coral reefs are crucial ecosystems that support millions of people around the world. They provide a source of livelihood and food for many coastal communities. The given answer of 500 million indicates the number of people who rely on coral reefs for their livelihoods and food. This suggests that a significant portion of the global population depends on these reefs for their well-being and sustenance.
8.
8.What are destructive fishing practices?
Correct Answer
D. All of the above
Explanation
Destructive fishing practices refer to methods that cause significant harm to marine ecosystems and fish populations. Overfishing involves catching fish at a rate that exceeds their ability to reproduce, leading to depletion of fish stocks. Blast fishing involves using explosives to stun or kill fish, causing damage to coral reefs and other habitats. Cyanide fishing involves using cyanide to stun fish, which not only harms the targeted fish but also damages coral reefs and other marine life. Therefore, all of the mentioned practices are considered destructive as they have negative impacts on the environment.
9.
9. What are coral reefs made out of?
Correct Answer
A. Coral polyps
Explanation
Coral reefs are made out of coral polyps. Coral polyps are tiny, soft-bodied organisms that secrete a hard calcium carbonate skeleton. These polyps live in colonies and form the structure of the coral reef. They have a symbiotic relationship with microscopic algae called zaoxanthellae, which live inside their tissues and provide them with nutrients through photosynthesis. The tentacles of coral polyps are used for feeding and capturing prey, but they do not make up the actual composition of the coral reef.
10.
10.The coral is dead once the coral bleached.
Correct Answer
B. False
Explanation
The statement is false because coral bleaching does not necessarily mean that the coral is dead. Coral bleaching occurs when the coral expels the algae living inside it, causing it to turn white. While prolonged bleaching can lead to the death of the coral if the algae does not return, some corals can recover and survive the bleaching event. Therefore, coral can be bleached but still alive.