Aim: How do organisms interact in an ecosystem?

Types of Relationships: Cooperative Competitive

Ecosystem Relationships: Symbiotic Relationships Mutualism – both benefit (+, +) Commensalism – one benefits and other is unaffected (+, 0) Parasitism – parasite benefits and host is affected (+, -) Predator & prey – predator benefits and prey is affected

Mutualism: The Nile crocodile opening its mouth to permit the Egyptian plover to feed on any leeches attached to its gums. Bee eats nectar & at the same time picks up pollen to be spread to other flowers.

Commensalism: Barnacles are non-motile, & they adhere to the fins of whales. This allows them to be taken to places where there is food. The whale is not affected.

Parasitism: Tick Fluke Worms Parasites are organisms that attack other live organisms called hosts.

Predator-Prey Relationship:

Why do organisms need to eat? To get ENERGY!! Cell Respiration: C6H12O6 + O2 ATP + CO2 + H2O

Organism Categories:

Organism Categories: Herbivores – eat only producers Carnivores – eat only meat Omnivores – eat both producers & meat

How do the cows we eat get their energy? Primary consumers get their energy from the producers they eat

How do producers get their energy? The primary source of energy for living things is the____. ________ capture this energy through a process of ____________ sun Autotrophs photosynthesis

How is energy transferred in a community?6 Energy is transferred by consuming other organisms

In which direction is the energy moving? Why?

Food Chains Food chains show the transfer of energy from one organism to another in a community

Show many food chains interconnected together Food Webs10 Show many food chains interconnected together

Energy Pyramid 11 2’ Consumers 1’ Consumers Producers 3’ Consumers Energy Flow 1’ Consumers Producers

Sun’s Energy in an Ecosystem12 Some of the energy is used by each organism and some of it is lost as heat energy to the environment

Why is there so little energy at the top of the pyramid? Most of the energy from the sun has been used or lost by organism in the lower levels Only about 10% of the energy available at each level is transferred to the NEXT level. 1% 10% 100%

Ecological pyramids Energy Pyramid Shows the relative amount of energy available at each trophic level. Organisms use about 10 percent of this energy for life processes. The rest is lost as heat. Go to Section:

Ecological pyramids Biomass Pyramid Represents the amount of living organic matter at each trophic level. Typically, the greatest biomass is at the base of the pyramid. Go to Section:

Ecological pyramids Pyramid of Numbers Shows the relative number of individual organisms at each trophic level. Go to Section:

In which direction is energy flowing?

The organisms in the food web below live near large cattle ranches The organisms in the food web below live near large cattle ranches. Over many years, mountain lions occasionally killed a few cattle. One year, a few ranchers hunted and killed many mountain lions to prevent future loss of their cattle. Later, ranchers noticed that animals from this food web were eating large amounts of grain from their fields. Identify two specific populations that most likely increased in number after the mountain lion population decreased. Support your answer. [2] Explain how killing many mountain lions affected other ranchers in the community. [1]