Station 16

Relationships Among Organisms

Reporting Category 5Interdependence Within Environmental Systems

Essential Question – Bell Ringer

What types of relationships may exist among the different organisms living

together in an ecosystem?

Parasitism, mutualism, commensalism, competition, and predator/prey

Pre-Review Question

True or False

Any relationship in which two species live close together is called “symbiosis”.

True

Pre-Review Question

A relationship in which one organism is helped and another organism is neither

helped nor hurt is called:

a.Mutualism

b.Parasitism

c.Competition

d.Commensalism

Pre-Review Question

A type of symbiosis in which one organism benefits and the other is harmed is called:

a. Mutualism

b. Parasitism

c. Predation

d. Commensalism

Draw this chart in your journal. Determine the relationship based on the card description.

Organisms Parasitism Commensalism Mutualism Predator/Prey Competition

1. Flea and Dog

2. Alligator and Bird

3. Fungus and Algae

4. Fly and Ant

5. Clown Fish and Sea Anemone

6. Cows and Cattle Bird

7. Scorpion and Moth

8. Plants

9. Aphids and Ants

10. Vines and Trees

11. Eagles and Fish

12. Rams

13. Lichen and Trees

Check your answers:

Parasitism: flea and dog, fly and ant

Commensalism: cows and cattle egrets, lichen and tree

Mutualism: Alligator and bird, fungus and algae, clownfish and sea anemone, aphids and ants

Predator/Prey: Scorpion and moth, hawks and fish

Competition: plants, plants and trees, vines and trees,

rams

Part 2 - Food Web: Use this food web to answer the questions on the next three slide.

Discuss with partner.Based on the food web from the previous slide,…

14. Which organism, the roadrunner or the owl, competes more for its food? What evidence in the food web confirms this?

The roadrunner competes more for its food, since it has to compete with the lizard. In this food web, the owl does not have to compete for food with any other organisms.

15. Which organism in the food web exists only as a predator?

The bobcat, since no other organism in the food web preys on it.

Draw the chart in your journal and determine if the organism is

a predator, prey or both. Use the food web to help you.

Answers

Discuss with partner

17. Explain why some organisms may be both predator and prey.

The roadrunner preys on lizards and other organisms, but is preyed upon by the owl. The owl, in turn, is preyed upon by the bobcat. In this food web, only the plants (the cone flower and the grass prairie) are prey only, and only the bobcat is a predator only.

• Organisms in an ecosystem exhibit different types of relationships as they interact.

• Some ways organisms interact is by competing for food and other resources.

• Relationships that may be found in an ecosystem include parasitism, commensalism, mutualism, and predator/prey.

I need to remember………

Post Review Question

A form of symbiosis in which both organisms benefit is called:

a.Mutualism

b.Parasitism

c.Commensalism

d.Predation

Post Review QuestionEcosystems consist of a wide variety of organisms. In an ecosystem with scattered open woodlands and streams, the black rhinoceros flourishes. Tick birds feed on insects on the rhino’s body. The rhino is warned of danger by the calls of the tick birds. Both the tick birds and the rhinos benefit from this association. The relationship between the bird and the rhino is an example of:

a.Commensalism

b.Mutualism

c.Parasitism

d.Predation

Post Review QuestionIn Tanzania, cape buffaloes are often found grazing in the grasslands with birds called cattle egrets nearby. The buffaloes flush insects out of the grasses, and the birds eat the insects. The buffaloes do not appear to be helped or harmed by the relationship. What kind of relationship does this demonstrate?a.Predation

b.Parasitism

c.Commensalism

d.Mutualism