Biology of Coral Reefs Exam 2 Review

Macroalgae

Large, photosynthetic algae that grow in marine environments, often providing habitat and food for various reef organisms.

The primary builders of coral reefs are __________ corals, which belong to the class __________.

Scleractinian; Anthozoa

The process by which corals deposit calcium carbonate to build their skeletons is called __________.

Calcification

Coral reefs are found in warm, shallow waters between __________ degrees north and __________ degrees south latitude.

30; 30

The symbiotic algae that live inside coral polyps and provide them with energy through photosynthesis are called __________.

Zooxanthellae

In coral competition, some corals use __________ tentacles to attack and damage neighboring colonies.

Sweeper

__________ reefs experience elevated salinity due to evaporation and limited freshwater input, as seen in the Persian Gulf.

Semi-enclosed

The three major types of symbiosis are __________, __________, and __________.

Mutualism, commensalism, parasitism

__________ is the term for the movement of zooxanthellae toward their coral host in response to ammonium waste.

Chemotaxis

__________ sponges erode limestone structures by boring into calcium carbonate skeletons.

Bioeroding

The symbiotic relationship between clownfish and anemones is an example of __________.

Mutualism

Which of the following is NOT a primary factor influencing coral reef distribution?

a) Light availability

b) Ocean salinity

c) Wind speed

d) Water temperature

Wind speed

What is the primary role of zooxanthellae in coral reef ecosystems?

Photosynthesizing and providing nutrients to the coral host

What is the main threat to corals that leads to bleaching events?

Elevated sea surface temperatures

What type of coral growth results in leafy colonies found in deep reef slopes with low light?

Leafy colonies

Which of the following organisms is responsible for nitrogen fixation in coral reef ecosystems?

Cyanobacteria

What is the maximum depth where coral reefs can typically form?

75 meters

What type of symbiotic relationship exists between a remora and a shark?

Commensalism

Which of the following contributes to bioerosion in coral reefs?

Clionidae Sponges

What is the main factor influencing coral skeleton formation?

Water temperature

In which way do corals primarily acquire nitrogen in nutrient-poor reef environments?

a) Through zooxanthellae nitrogen fixation

b) By absorbing nitrates from seawater

c) By eating plankton

d) All of the above

All of the above

Explain the importance of coral reef ecosystems in marine biodiversity.

Coral reefs provide habitat for a vast diversity of marine organisms, serve as breeding and nursery grounds, and protect coastlines from erosion.

Describe two methods corals use to compete for space on reefs.

Corals use overtopping (growing over competitors) and aggressive behavior (e.g., sweeper tentacles, mesenterial filaments) to compete for space.

What are the primary abiotic factors that influence coral reef growth and development?

Temperature, salinity, light availability, nutrient levels, and exposure to wave action influence reef growth.

How do symbiotic bacteria benefit reef sponges?

Symbiotic bacteria in sponges help with nutrient cycling, bioerosion, and filtering water, benefiting reef ecosystems.

What is the adaptive bleaching hypothesis, and how does it relate to coral resilience?

The adaptive bleaching hypothesis suggests that corals can switch their zooxanthellae to more heat-tolerant strains, improving resilience to temperature changes.

Discuss the role of symbiosis in coral reef ecosystems.

Include examples of mutualism, commensalism, and parasitism, as well as how these interactions influence reef structure.

Examples: Zooxanthellae and corals (mutualism), Remoras and sharks (commensalism), Crown-of-thorns starfish and coral (parasitism).

Benefits of mutualism: Nutrient sharing, increased survival.

Impact on reef biodiversity and structure.

Explain the effects of climate change on coral reef ecosystems.

Include how increased sea surface temperatures, ocean acidification, and human activities contribute to reef degradation.

Rising sea temperatures → coral bleaching

Ocean acidification → reduced coral calcification

Coastal development & pollution → habitat destruction

Overfishing → imbalance in reef ecology