EQ: How do Energy and Matter Move In an Ecosystem?

Sunlight is the main source of energy for life on Earth. Producers/Autotrophs – use energy from the environment (often sunlight) to make their own food - Ex: Plants and algae

Plants and algae make food in a process called Photosynthesis Remember…6CO 2 + 6H 2 O  6O 2 + C 6 H 12 O 6

Consumers/Heterotrophs Get energy from the food they eat.

Types of Heterotrophs Herbivores – eat plants (ex. cows) Carnivores – eat other animals (ex. lions)…some even eat dead stuff… they are called Scavengers Omnivores – eat plants and animals (ex. humans) Decomposers – break down dead organic matter for energy (ex. Bacteria and fungi)

Tracking Energy Flow Food Chains: series of steps in an ecosystem in which organisms transfer energy by eating and being eaten. sun  willow  elk  wolf

Each step in a food chain is called a trophic level 1 st level: Producers 2 nd level: Primary (first level) Consumers 3 rd level: Secondary (second level) Consumers 4 th level: Tertiary (third level) Consumers Top level consumer in an ecosystem is called the Apex predator

Food webs – shows network of food chains in an ecosystem

Arrows show the direction energy is being transferred. leaf caterpillar robin Rule of 10 – only 10% of the energy available in one trophic level is transferred to organisms at the next level. Most energy is lost as heat.

Community Interactions Competition – for food, water, shelter, mates Predation Symbiosis – two species live closely together

Types of Symbiosis 1.Mutualism – both species benefit 2.Commensalism – 1 organism benefits; the other is unharmed 3.Parasitism – 1 benefits, 1 is harmed

Mutualism Commensalisms Parasitism

Habitat – where an organism lives Niche – an organism’s specific role in its environment Ex. Place in food web

Limiting Factors Limiting factors are things in an environment that prevent a population from growing infinitely. Examples include things such as: water, food, mates, space, air, etc. All populations are kept in check by limiting factors.

Carrying Capacity The largest population that an environment can support Once carrying capacity is reached populations will begin to decrease as individuals move away or die off because of limiting factors.