Interactions in Marine Ecosystem

Interactions in the ecosystem:

Parasitic Relationships

A parasitic relationship occurs when one organism (parasite) lives on or inside a host, gaining nutrients or other benefits, while the host suffers harm.

  • Example: Copepods and Marine Fish:

    • Copepods (parasites) attach to the skin, gills, or mouth of marine fish.

    • They feed on the fish’s blood, mucus, or tissue.

    • Harm to fish: Causes wounds, infection, reduced fitness, or difficulty breathing (if gills are affected).

Commensal Relationships

A commensal relationship occurs when one organism benefits, while the other is unaffected.

  • Example: Manta Rays and Remora Fish:

    • Remora Fish use suction discs to attach to the underside of manta rays.

    • Benefits to remoras:

      • Transport.

      • Access to leftover food scraps.

    • No significant effect on the manta ray.

Mutualistic Relationships

A mutualistic relationship is when both organisms benefit from the interaction.

  • Example: Boxer Crabs and Anemones:

    • Boxer Crabs carry small sea anemones in their claws.

    • Benefits to the crab:

      • Anemones sting predators, providing protection.

    • Benefits to the anemones:

      • Mobility helps them access more food (plankton).

  • FEEDING RELATIONSHIPS

    • Primary Consumers: feed on producers.

    • Secondary Consumers: feed on primary consumers.

    • Tertiary Consumers: feed on secondary consumers.

    • Quaternary Consumers: feed on tertiary consumers.

    Producer- synthesizes its own organic compounds, primarily through photosynthesis or chemosynthesis, forming the base of the food chain.

    Herbivore

    Consumers that feed exclusively on producers.

    Carnivore

    Consumers that feed exclusively on other animals

    Omnivore

    Consumers that feed on both plants and animals

    Decomposer

    Organisms, such as bacteria and fungi, that break down dead organic material into inorganic minerals, recycling them back into the ecosystem.

    Predator

    An organism that hunts and consumes prey for energy.

    Prey

    Organisms that are hunted and consumed by predators

    Food Chain

    Shows the flow of energy from one organism to another. Example:

    Phytoplankton → Zooplankton → Small Fish → Tuna → Shark

    Food Web

    Trophic Level

    • Trophic Level 1: Producers.

    • Trophic Level 2: Primary consumers.

    • Trophic Level 3: Secondary consumers.

    • Trophic Level 4: Tertiary consumers, and so on.

    Photosynthesis captures the energy of sunlight and makes some of the energy available to the food chain. carbon dioxide + water light →glucose + oxygen (in the presence of light and chlorophyll)

    Some of the glucose produced by photosynthesis is used to produce biomass.

    Some of the glucose produced by photosynthesis is used in respiration to provide usable energy glucose + oxygen → carbon dioxide + water

    Productivity is the rate of production of biomass per unit area.

    Primary productivity is the amount of new biomass made by primary producers. Most energy is not passed to consumers it is lost in respiration.

    GROSS PRIMARY PRODUCTION - RESPIRATION=NET PRIMARY PRODUCTION (passed on to consumers)

  • NUTRIENT CYCLES

    Nutrients are substances that are required by an organism for growth, repair, energy or normal metabolism.

    Nutrients can include gases such CO2, ions such as Mg2+, CO3 2–, PO4 3– and NO3– and organic compounds such as carbohydrates, lipids and proteins.

    The chemical elements that make up carbohydrates, lipids and proteins

    Carbohydrates- carbon, hydrogen, oxygen.

    Lipids- Carbon, hydrogen, Oxygen.

    Protein- Carbon, hydrogen, oxygen, nitrogen.

    Large molecules are made from smaller molecules, limited to starch and cellulose from glucose, proteins from amino acids, and lipids from fatty acids and glycerol.

    Elements have important biological roles: • nitrogen, which is used to make proteins, chlorophyll and DNA • carbon, which is used to make all organic compounds • magnesium, which is used to make chlorophyll • calcium, which is used to make bones, shells and coral skeletons • phosphorus, which is used to make DNA and bones.

    some nutrients are soluble and that there is a reservoir of these nutrients dissolved in the ocean which is available to producers and consumers.

    Factors that add nutrients to the reservoir Factors that remove nutrients from the reservoir

    Upwelling- cold nutrient rich water brought to the surface

    Uptake of nutrients by organisms

    Runoff- dissolved nutrients carried into ocean by water

    Marine snow- death and sinking which may eventually become sediments on the ocean floor by heat and pressure.

    Tectonic activity- hydrothermal vents, volcanoes- that precipitate nutrients

    Harvesting

    Dissolving of atmospheric gases

    Excretion

    Decomposition

    explain why productivity may be limited by the availability of dissolved nutrients

    DESCRIBE Carbon cycle, limited to combustion, photosynthesis, respiration, decomposition, formation of fossil fuels, formation and weathering of rocks containing carbonate.