Vocabulary 1. Ecosystem – interactions between the biotic organisms and the abiotic materials and how materials and energy are transferred 2. Biotic – living or dead organisms; made up of cells Examples – plants, animals 3. Abiotic – non-living materials Examples – plastic, oxygen, water, rocks, light, heat 4. Producers – turn the sun’s light energy into chemical (food) energy. They make their own food b y the process called PHOTOSYNTHESIS Producers are only in the first trophic level Examples – plants, algae, bacteria

5. Consumers – cannot make their own food (chemical energy) Use chemical energy from other living organisms Need to eat Producers or Consumers to get their food energy Found on the second or higher trophic levels 6. Primary consumers – first consuming organism in a food chain Second trophic level Examples – herbivores or omnivores 7. Secondary consumers – second consuming organism in a food chain Third trophic level Examples – carnivores or omnivores 8. Tertiary consumers – third consuming organism in a food chain Fourth trophic level Examples – carnivores or omnivores

9. Trophic level – feeding level 10. Herbivore – only eat producers (such as plants) 11. Carnivores – eat consumers (herbivores or carnivores or omnivores) 12. Omnivores – eat producers or consumers 13. Food chain – starts with a producer and only connects with single links (arrows) to the consumers Example – a typical food chain in a field ecosystem might be: grass  grasshopper  mouse  snake  hawk 14. Food web – multiple food chains that interconnect showing many feeding relationships

15. Scavengers – feed on the bodies of larger dead animals Examples – vultures, eagles, ravens, hyenas, some ants, and beetles 16. Detrivores – feed on bodies of smaller dead animals and plants Examples – crabs, earthworms, wood beetles, carpenter ants 17. Decomposer – feed on any remaining dead plant and animal matter Examples – bacteria, fungi

18. Population – organisms that belong to the same species that live in the same ecosystem Example – people: species in Halifax: ecosystem 19. Carrying capacity – largest population of a species that an ecosystem can support 20. Competition – demand for resources Examples – food, water, mates, space 21. Population density – the number of organisms within a given space

Vocabulary 22. Predators – an organism that hunts other organisms 23. Prey – an organism that is hunted by a predator 24. Niche – an animal’s role in its ecosystem 25. Habitat – a place where a population lives 26. Biome – ecosystems where several habitats intersect 27. Cellular respiration – the process of breaking down food  C6H12O6 + O2  ENERGY + H2O + CO2

OBTAINING ENERGY Every organism needs to obtain energy in order to live The sun is the Earth’s main source of energy  Plants get energy from the sun  Some animals eat plants  Some animals eat other animals

FOOD CHAINS AND WEBS We organize the flow of energy in ecosystems using food chains and webs  A food chain is the sequence of who eats whom in a biological community (ecosystem) to obtain nutrition  A food web is a network of many food chains

FOOD CHAINS A food chain starts with the primary energy source  Usually the sun The next link in the chain is an organism that makes its own food from the primary energy source  Photosynthetic plants that make their own food from sunlight  Also called autotrophs or primary producers Next come organisms that eat the autotrophs  Called herbivores or primary consumers  A rabbit that eats grass

FOOD CHAINS CONTINUED The next link in the chain is animals that eat herbivores  Called secondary consumers  Snakes that eat rabbits Next are tertiary consumers  Owl that eats snakes The last link in the chain are quaternary consumers  Hawk that eats owls EACH FOOD CHAIN ENDS WITH A TOP PREDATOR, AN ANIMAL WITH NO NATURAL ENEMIES (LIKE AN ALLIGATOR, HAWK, OR POLAR BEAR)

The arrows in a food chain show the flow of energy from the sun to a top predator As the energy flows from organism to organism, energy is lost at each step

EXAMPLE OF A FOOD CHAIN

EXAMPLE OF FOOD WEB

ANOTHER EXAMPLE OF A FOOD WEB

IMPORTANT INFORMATION TO KNOW Some organisms’ position in the food chain can vary as their diet differs  For example – when a bear eats berries, the bear is functioning as a primary consumer. When a bear eats a plant-eating rodent, the bear is functioning as a secondary consumer. When a bear eats salmon, the bear is functioning as a tertiary consumer  This is because salmon is a secondary consumer since it eats herring that eat zooplankton that eat phytoplankton that make their own energy from the sun  THINK ABOUT HOW PEOPLE’S PLACE IN THE FOOD CHAIN VARIES – OFTEN WITHIN A SINGLE MEAL!

MORE IMPORTANT INFORMATION TO KNOW In any food web, energy is lost each time one organism eats another  Because of this, there are many more plants than there are plant-eaters  There are more autotrophs than there are heterotrophs  More plant-eaters than meat eaters Each level has about 10% less energy available to it because some of the energy is lost as heat at each level

MAINTAINING EQUILIBRIUM As the number of carnivores in a community increases, they eat more and more of the herbivores This decreases the herbivore population It then becomes harder and harder for the carnivores to find herbivores to eat This decreases the carnivores population In this way, the carnivores and herbivores stay in a relatively stable equilibrium by limiting each other’s population A similar equilibrium exist between plants and plant- eaters

5 Levels of Ecological Organization 1. Organism – a living thing 2. Population - organisms that belong to the same species that live in the same ecosystem 3. Community – made up of living things within a specific geological area 4. Ecosystem - interactions between the biotic (living) organisms and the abiotic (non-living) materials and how materials and energy are transferred 5. Biosphere – all ecosystems of the Earth combined

Bellwork 1. Which statement describes the niche of an organism in an ecosystem? (Remember, a niche is an organism’s role in its ecosystem.) a) A pelican is able to fly long distances without stopping b) A snake feeds on small rodents in a forest c) A moth is nocturnal and is attracted to light d) A frog spends part of its life in water and part on land TURN IN THIS WEEK’S BELLWORK AND WRITING PROMPT STUDY FOR YOUR QUIZ