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 level10. Herbivore – only eat producers (such as plants)11. Carnivores – eat consumers (herbivores or

carnivores or omnivores)12. Omnivores – eat producers or consumers13. 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 ecosystem25. Habitat – a place where a population lives26. 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 owlsEACH 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 populationIt then becomes harder and harder for the

carnivores to find herbivores to eatThis decreases the carnivores populationIn 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 thing2. 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 forestc) A moth is nocturnal and is attracted to lightd) A frog spends part of its life in water and part on

land

TURN IN THIS WEEK’S BELLWORK AND WRITING PROMPTSTUDY FOR YOUR QUIZ