Question

_____ are low ridges, typically made of coral, that rise to or near the ocean's surface.

Answer 1

Coral Reefs

Step-by-step explanation:

Coral Reefs are an ecosystem containing 25% of marine species made of calcium carbonate from dead organisms and shells, the coral reef is located relatively near to the surface from 50 m to 2mts in the reef crest , its Extention is based on the temperature and solar radiation, therefore coral reefs aren't present at depth lower than 100 m. The reef is divided in into 4 main parts:

Reef flat: located near the shore behind the reef crest, its made of plains and concave zones forming lagoon-like ponds made from coral rock and loose sand, at low tide the reef flat tends to be exposed.

Reef crest: Its a crest located where the waves hit forming this raised part of the reef that is exposed at low tides, and because of its proximity to the surface (2mts) and the power of the waves, its not an ideal zone for corals.

Buttress zone: its main function is to dissipate the force of incoming waves and maintaining the reef's structure, located after the reef crest and before the Reef´s wall.

Deep fore Reef (Wall): its the dropoff of the reef, because of its depth (50 m) this high steep zone is ideal for corals and because of not being exposed to waves they stick to the seabed..

Answer 2

Reefs are low ridges, typically made of coral, that rise to or near the ocean's surface.

Reefs are low ridges that rise to or lie near the ocean’s surface. Reefs usually lie at a length of 80 meters or less under low water. They are usually composed of coral, rocks or sands. Some reefs are formed from abiotic processes such as wave erosion, sand deposition while some reefs (such as coral reefs) are formed from biotic processes. An example of a reef is the Great Barrier Reef in Australia. This reef is the largest and the most popular reef on earth.