Living Together: Symbiosis in Ecosystems

Learning Objectives

• Define symbiosis and describe mutualism, commensalism and parasitism.
• Classify relationships between organisms using evidence of benefit or harm.
• Explain how symbiotic relationships affect the survival of species and the balance of an ecosystem.

How to Use This Resource

• Start with slide 1: a photo-style prompt of a clownfish in a sea anemone. Ask, "Why doesn't the anemone sting the clownfish?"
• Teach the three types of symbiosis with the slides and the plus-zero-minus code, then do activities 1 and 2 together.
• Students complete activities 3 to 6, then use the quiz to check and the homework partner cards. Answers are in the answer key.

Classroom Activity Ideas

• Partner hunt: give each student a card with one organism. Students find their symbiotic partner and decide together which type of relationship they have.
• Plus, zero, minus: hold up a relationship and students show + +, + 0 or + − with hand signals.
• Schoolyard survey: look for lichen on walls or trees, insects visiting flowers or galls on leaves, and record the relationships found.

Differentiation

Support: give a plus-zero-minus chart with picture examples and a word bank. Challenge: research lichen (a partnership between a fungus and an alga) and explain why scientists call it mutualism.

Assessment

Worksheet activities 1 to 5 and the quiz check the three types, classification and comparison with other relationships (answer key included). Activity 6 and the homework are assessed with the rubric.

Teacher Tips

Students often confuse parasitism with predation. Point out that a parasite usually lives on or in its host for a long time and needs the host to stay alive, while a predator eats its prey quickly.

What's Included

• 11-page printable PDF lesson pack: teacher lesson plan with timings, materials and differentiation
• Key vocabulary list (8 words with meanings and examples)
• Student worksheet (6 activities)
• Quiz / assessment (3 parts)
• Homework practice page
• Printable flashcards: 8 A5 picture cards (separate PDF)
• Assessment rubric (4 levels)
• Lesson slides (editable PowerPoint)
• Editable Word version of all student pages
• Complete answer key (also as a separate PDF)

Additional Files

• Lesson Slides (PPTX)
• Editable Student Pages and Lesson Plan (DOCX)
• A5 Flashcards (PDF)
• Answer Key (PDF)

Teacher Reviews