Coral

Definition

Coral refers to marine invertebrates within the class Anthozoa, primarily found in tropical oceans, that live in colonies made up of numerous identical polyps. These polyps secrete calcium carbonate, forming a hard exoskeleton that contributes to the structure of coral reefs, which are vital ecosystems supporting diverse marine life. Corals are also symbiotic organisms, hosting algae called zooxanthellae, which provide them with energy through photosynthesis, highlighting their importance in marine ecology.

5 Must Know Facts For Your Next Test

1. Corals can reproduce both sexually and asexually; sexual reproduction involves the release of eggs and sperm into the water, while asexual reproduction occurs through budding.
2. Coral reefs are sometimes referred to as the 'rainforests of the sea' due to their high levels of biodiversity, providing habitat for countless marine species.
3. Coral polyps have a simple body structure featuring a mouth surrounded by tentacles armed with specialized cells called nematocysts for capturing prey.
4. The health of coral reefs is closely linked to environmental conditions; factors like ocean acidification and pollution can severely impact coral growth and survival.
5. Coral reefs cover only about 0.1% of the ocean floor but support approximately 25% of all marine life, showcasing their ecological significance.

Review Questions

• How do coral polyps contribute to the formation and maintenance of coral reefs?
  • Coral polyps contribute to the formation and maintenance of coral reefs by secreting calcium carbonate, which forms a hard exoskeleton. This exoskeleton builds up over time as more polyps grow and reproduce, creating the complex structure of the reef. The collective growth of these colonies leads to the establishment of extensive reef systems that provide habitats for diverse marine organisms.
• Discuss the role of zooxanthellae in coral health and how environmental changes can affect this relationship.
  • Zooxanthellae play a crucial role in coral health by providing energy through photosynthesis, which is vital for the survival of corals. In return, these algae receive protection and access to sunlight from the coral host. Environmental changes, such as rising sea temperatures or pollution, can stress corals and lead to bleaching, causing them to expel their zooxanthellae. This loss can significantly diminish the energy supply for corals and ultimately threaten their survival.
• Evaluate the impact of human activity on coral reef ecosystems and propose potential strategies for conservation.
  • Human activities such as coastal development, pollution, overfishing, and climate change have had devastating impacts on coral reef ecosystems. These pressures lead to issues like coral bleaching and habitat destruction. To conserve these vital ecosystems, strategies could include establishing marine protected areas, implementing sustainable fishing practices, reducing carbon emissions to combat climate change, and increasing public awareness about the importance of coral reefs for biodiversity and coastal protection.

Related terms

Zooxanthellae: Symbiotic algae that live within the tissues of coral polyps, providing them with energy through photosynthesis while benefiting from the protection and nutrients provided by the coral.

Coral Reef: A large underwater structure composed of coral polyps and their calcium carbonate skeletons, known for its biodiversity and as a habitat for various marine organisms.

Bleaching: A stress response in corals caused by environmental changes, such as increased water temperature, leading to the expulsion of zooxanthellae and loss of color, which can result in coral death if conditions do not improve.