Ecosystems, Habitats, and Symbiotic Relationships

Ecosystem

  • An ecosystem consists of organisms living together and interacting with each other and their environment.

  • Definition is simple to memorize but important for exams.

Habitat

  • A habitat is the place where an organism lives, with an environment made of physical and living features.

Abiotic vs. Biotic

  • Abiotic: Non-living (physical) features.

  • Biotic: Living features.

Abiotic Environment (Non-Living Features)

  • Important for survival:

    • Temperature: Maintained by the sun.

    • Light: Essential for photosynthesis.

    • Water

    • Air

    • Soil

Biotic Environment (Living Features)

  • Consists of all the organisms living in a habitat.

  • Organisms interact and form relationships.

    • Competition

    • Predator and Prey

    • Symbiosis

Relationships

Competition

  • Plants compete for sunlight (growing taller) and water/minerals (roots going deeper).

  • Animals compete for food, especially with predators.

  • Humans compete for jobs, grades, etc.

Predator and Prey

  • Predators hunt prey for food and survival.

Symbiosis

  • Classified into three subcategories:

    • Parasitism

    • Commensalism

    • Mutualism

Parasitism

  • One side (parasite) benefits at the expense of the other (host).

  • Example: Mosquito biting a person.

    • Mosquito benefits (gets blood).

    • Person is harmed (itchy bite, potential diseases like dengue).

Commensalism

  • One side benefits, the other is not significantly helped or harmed.

  • Example: Climber plants (orchids, money plants) climbing on a tree.

    • Climber plant benefits (gains sunlight).

    • Tree is not affected.

Mutualism

  • Both sides benefit.

  • Example: Teacher and students.

    • Students gain knowledge.

    • Teacher improves teaching through student feedback.

Symbiosis Examples in Nature

Parasitism

  • Wasps lay larvae on a caterpillar. The larvae benefit, and the caterpillar dies after serving its purpose.

Commensalism

  • Remora fish attaches to a larger fish. The remora fish benefits because it has the free ride so it gets to eat.

Mutualism

  • Sea anemone cannot move to catch prey. Clownfish acts as a lure to attract sea creatures to the sea anemone which poisons the fish so that it can eat them. Clownfish is protected and eats the remains of the dead fish.