What is the mutualistic relationship between coral polyps and zooxanthellae ?
- Zooxanthellae gain shelter/habitat/protection
- Coral polyps receive nutrients from zooxanthellae (C₆H₁₂O₆, D.O.)
- Zooxanthellae use coral waste products for photosynthesis (CO₂, NO₃, PO₄)
This relationship is crucial for the survival of coral reefs.
How is the red mangrove adapted to its environment?
- Prop roots provide stability in muddy substrate
- Roots have membranes that keep salt out
- Roots allow oxygen to diffuse for respiration
- Leaves excrete salt
- Displays viviparous reproduction (live birth)
The adaptations help red mangroves thrive in brackish water conditions.
What factors affect the distribution and abundance of organisms on a rocky shore?
- Exposure time in air
- Dissolved oxygen concentration
- Competition
Biodiversity increases down the shore, with organisms adapting to their specific zones.
What are the zones on a rocky shore?
- Splash zone
- Upper shore
- Middle shore
- Lower shore
Organisms in these zones have different adaptations to survive varying conditions.
List the main functional features of a typical coral polyp.
- Tentacles: capture prey; house zooxanthellae
- Nematocysts: stinging cells that release toxins
- Mouth: prey in, waste out
- Stomach: absorbs nutrients
- Calyx: stony cup in which polyp sits
- Theca: walls of calyx
- Basal plate: separates polyp from substrate
Each feature plays a vital role in the polyp’s survival and function.
What factors can lead to coral reef erosion?
- Predators (e.g., crown of thorns sea star)
- Ocean acidification/global warming
- Hurricanes
- Exposure to air
- Disease (e.g., stony coral tissue loss disease)
- Tourism (human and ship damage)
- Destructive fishing methods (e.g., blast fishing)
These factors threaten the health and stability of coral reefs.
Describe the features of a sandy shore.
- Gradual slope towards the ocean
- Subject to wind and water erosion
- Constantly moving substrate
- Low productivity/small food chain
Organisms must adapt to these challenging conditions to survive.
How do corals help protect coastlines?
- Prevent coastal erosion
- Absorb wave energy
- Protect coastal properties and ecosystems
- Reduce costs of artificial breakwaters
- Prevent flooding
- Provide safe anchorage for boats
Coral reefs play a crucial role in coastal protection.
What type of habitat do mangroves grow in?
- Tropics/subtropics
- Littoral zone
- Shallow water
- Muddy substrate/high levels of sedimentation
- Brackish water (salinity varies)
- Low dissolved oxygen in substrate
Mangroves thrive in these unique coastal environments.
What is a disadvantage of genetically engineering coral?
*Lowered genetic diversity
This makes them more susceptible to diseases.
Why do tropical corals rarely grow in deeper water?
- Not enough light for photosynthesis
- Water temperature is too cold
These conditions are critical for coral survival.
What conditions are required for the growth of tropical reef building corals?
- Warm water (~25℃)
- Clear, non-turbid water
- Rocky substrate
- Shallow depth (up to 20m)
- Average salinity of ~35 ppt
- Non-acidic water
These conditions support the health and growth of coral reefs.
List the five oceans from largest to smallest.
- Pacific
- Atlantic
- Indian
- Southern
- Arctic
Understanding ocean sizes is important for geographical knowledge.
Explain the Darwin-Dana-Daly theory of atoll formation.
- Oceanic volcano emerges
- Coral polyps colonize if conditions are suitable
- Fringing reef forms
- Subsidence begins
- Barrier reef forms with a lagoon separating it from the island
- Island subsides, leaving a ring of islands with a lagoon
This theory explains the formation of atolls in oceanic environments.
What are two properties of reef balls that make them suitable for constructing artificial reefs?
- Holes provide habitat and facilitate sinking
- Suitable substrate for attachment of sessile organisms
- Heavy/sturdy to prevent being washed away
- Non-corrosive/non-toxic to avoid toxins entering the food chain
These properties enhance the effectiveness of artificial reefs.
Why does a rocky shore have greater biodiversity than a sandy shore?
- Not easily eroded
- Substrate for attachment
- Higher productivity and larger food web
- Vertical zonation and tide pools
These factors contribute to a more diverse ecosystem.
State three reasons for the loss of mangroves.
- Deforestation/timber
- Hurricane/tsunami damage
- Coastal development
These activities threaten mangrove ecosystems.
How does a rocky shore form and what community is found there?
- Formed by slow erosion
- Tide pool communities are found here
Environmental factors influence life in these communities.
What are the roots of the red and black mangrove and their functions?
- Red mangrove: prop roots trap particles, increasing sedimentation
- Black mangrove: pneumatophores obtain oxygen from the air
These adaptations are essential for their survival in coastal environments.
How do coral polyps obtain nutrition? Describe both methods.
- Mutualistic association with zooxanthellae
- Capture prey with tentacles containing nematocysts
Each method is vital for the polyp’s energy and nutrient acquisition.
Define the term vertical zonation.
The distribution of organisms at different elevations on a rocky shore
This concept helps explain how organisms adapt to varying environmental conditions.
