ENV201 Lesson 2: Interactions in the Ecosystem

2.1 Understanding Ecosystems, 2.2 Environmental Interactions, 2.3 Habitat and Niche, 2.4 Evolution and Adaptation

Ecosystem

• Community of living organism

• Living with non-living and living organisms

• Made up of two main parts: abiotic and biotic components that maintain a balanced and functioning environment

Biotic Components

• Living organisms in an ecosystem, regardless of the size

• Depend on one another and on abiotic factors for survival

• Characteristics:

  • Living organisms

  • Grow and reproduce

  • Interact with other organisms

  • Depend on abiotic factors to survive

Biotic Categories

• Producers (Autotrophs)

• Consumers (Heterotrophs)

• Detritivores

• Composers

Autotrophs

• are the Producers

• make their own food using sunlight through photosynthesis

• primary source of energy in most ecosystems

• ex. Grass, Trees, Algae, Ferns, Cactus

Heterotrophs

• are the Consumers

• they cannot make their own food

• they obtain energy by eating plants or other animals

• ex.

Heterotroph Types

• Herbivores (plant-eaters)

• Carnivores (meat-eaters)

• Omnivores (plant and meat eaters)

Herbivores

• plant-eaters

• ex. Carabao, Cow, Rabbit, Caterpillar

Carnivores

• meat-eater

• ex. Lion, Tiger, Eagle, Snake, Shark

Omnivores

• both plant and meat eaters

• ex. Human, Bear, Pig, Chicken, Dog

Decomposers

• break down dead plants, animals, and organic matter into simpler substances, returning nutrients to the environement

• Ex. Mushroom, Bacteria, Mold, Fungi, Yeast

Detritivores

• feed on dead organic matter by breaking it into smaller pieces

• ex. earthworm, millipede, termite, maggot

Abiotic Components

• These are the non-living physical and chemical factors in an ecosystem.

• They provide the conditions and resources that living organisms need to survive, grow, and reproduce.

• Chracteristics:

  • Non-living

  • Cannot grow or reproduce

  • Influence where organisms can live

  • Affect the survival and distribution of living things

Organisms

• living in the same habitat constantly interact

• their interactions help maintain ecological balance

Interaction Types

• Competition

• Predation

• Mutualism

• Commensalism

• Parasitism

• Decomposition

Competition

• an interaction in which two or more organisms compete for the same limited resource

• both organisms are negatively affected (-/-)

• occurs within the same species (intraspecific) or between different species (inter

Predation

• interaction in which one organism (the predator) hunts, kills, and eats another organism (the prey)

• the predator benefits (+)

Mutualism

• interaction in which both organisms benefit from their relationship

• both organisms benefit (+/+)

Commensalism

• interaction in which one organism benefits while the other is neither helped nor harmed

• One organism benefits (+)

• other organism is unaffected (0)

Parasitism

• an interaction in which one organism (the parasite) benefits while the other (the host) is harmed

• parasite benefits (+)

• host is harmed (-)

Decomposition

• process by which decomposers break down dead plants, dead animals, and organic wastes into simpler substances

Habitats

• natural environment or place where an organism lives

• provides everything an organism needs to survive

• provide food, water, shelter, and space for organisms

• support growth, survival, and reproduction

• maintain biodiversity by supporting different species

Niche

• organism’s profession within its home

• what it eats, where it lives, how it survives, how it reproduces, how it interacts with other organisms

Evolution

• gradual change in the characteristics of populations over many generations

• changes occur because individuals with helpful traits are more likely to survive and reproduce passing those traits to their offspring

Adaptation

• inherited characteristic that helps an organism survive

• improves an organisms chances

Adaptation Types

• Structural Adaptation

• Behavioral Adaptation

• Physiological Adaptation

Structural Adaptation

• physical feature or body part that helps an organism survive

• involves organism’s body structure or appearance

• usually inherited and present through their life

• ex. giraffe’s long neck

Behavioral Adaptation

• action or behavior that helps an organism surivve

• involves organism’s actions or habits

• occur in response to environmental conditions or life stages

• ex. bats active at night, ants working together for food, cats stalk their prey

Physiological Adaptation

• internal body processses or chemical functions

• involves how the body works

• ex. snake produces venom, camel conserves water