Teacher pack: Symbiosis: mutualism, commensalism and parasitism (Grade 7)

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Teacher guide

Phase D · Lower secondary grade 7 · IPA

An original supplementary PanduanHewan resource; not an official module or specialist teacher review.

Goals

Students can explain what symbiosis is and its three types.
Students can classify pairs of organisms as mutualism, commensalism or parasitism using gain and harm.
Students can give examples of symbiosis involving Indonesian animals.
Students can tell symbiosis apart from predation and competition.

Materials

Picture cards of paired organisms
A poster with three columns: +/+, +/0, +/−
+, 0 and − cards
The symbiosis worksheet

Suggested timing, adaptable by the teacher

11 minutes introduction · 38 minutes activity · 14 minutes discussion · 7 minutes reflection (70 minutes).

Pair cards: groups get 12 picture cards of paired organisms, stick them in +/+, +/0 or +/− columns and explain why.
Ground-level observation: students look at plants growing on school trees, such as orchids or ferns, without climbing or removing them, then draw them and decide the relationship.
Short debate: groups discuss whether remoras and sharks are better called commensalism or mutualism, using evidence from the reading.
Who gains quiz: the teacher reads out a pair, and students raise +, 0 or − cards for each partner.

Suggested formative rubric

Teachers may adapt this. Score each criterion 0 (not yet shown), 1 (partly) or 2 (clear); the 0–6 total is not an official passing standard.

Concepts match the reading.
Reasoning is supported by an example or evidence.
Can revise an answer and identify uncertainty.

Symbiosis worksheet: mutualism, commensalism and parasitism (with answer key)

Name / class / date (complete on paper):

Reading

Symbiosis is a close, long-lasting relationship between two different kinds of living things. In mutualism both gain (clownfish and anemone), in commensalism one gains and the other is unaffected (orchid and tree), and in parasitism one gains and the other is harmed (cat flea and cat). It is taught in Indonesia's Grade 7 science book, Chapter VI.

Symbiosis has three main types: mutualism (+/+), commensalism (+/0) and parasitism (+/−).
Clownfish and sea anemones are mutualists: the anemone protects the fish, and the fish drives off the anemone's predators.
Epiphytic orchids are not parasites; they grow on trees without taking nutrients from them, so they are commensals.
Only female Aedes mosquitoes feed on blood, to produce eggs; their relationship with people is usually classed as parasitism, though ecologists call mosquitoes micropredators.
Cattle egrets mainly eat insects disturbed by buffalo, so the pair is usually classed as commensalism; if the egret eats ticks off the buffalo's hide, it becomes mutualism.
Symbiosis is different from predation and competition, which are also interactions between living things.

Activity 1

Decide the type of symbiosis for each pair (mutualism, commensalism or parasitism) and give your reason using +, 0 or −.

Pair of organisms	Type of symbiosis and reason
Clownfish and sea anemone
Asian honey bee and flowers
Large flying fox and durian tree
Knobbed hornbill and forest fruit trees
Giant clam and zooxanthellae
Orchid and mango tree
Remora and shark
Cattle egret and water buffalo
Cat flea and cat
Brown dog tick and dog
Female Aedes mosquito and people
Mistletoe and tree

Activity 2

Explain the difference between mutualism, commensalism and parasitism in your own words.
Why is an orchid growing on a tree not a parasite?
What does the clownfish get, and what does the sea anemone get, from their relationship?
Your friend says, "Buffalo and mynas are definitely mutualists." How would you respond?
How is predation different from parasitism?

Reflection

Which example of symbiosis can you find near your home or school?

Which type of symbiosis is hardest for you to tell apart? Why?

Why is it important to check whether an example in a book or online is backed by research?

Answer key — for teachers

Separate this section from pupil copies. Page numbers depend on print settings.

Activity 1

Clownfish and sea anemone: Mutualism (+/+): the fish is protected, the anemone is guarded from predators
Asian honey bee and flowers: Mutualism (+/+): the bee gets nectar and pollen, the flower is pollinated
Large flying fox and durian tree: Mutualism (+/+): the bat gets food, the tree is pollinated and its seeds spread
Knobbed hornbill and forest fruit trees: Mutualism (+/+): the bird gets fruit, the seeds are spread
Giant clam and zooxanthellae: Mutualism (+/+): the clam gets food, the algae get a home
Orchid and mango tree: Commensalism (+/0): the orchid gets a place to grow, the tree loses no nutrients
Remora and shark: Commensalism (+/0); can be close to mutualism because remoras also eat the shark's parasites
Cattle egret and water buffalo: Commensalism (+/0): the egret gets disturbed insects, the buffalo is unaffected (mutualism if the egret eats the buffalo's ticks)
Cat flea and cat: Parasitism (+/−): the flea gets blood, the cat is harmed
Brown dog tick and dog: Parasitism (+/−): the tick gets blood, the dog can become ill
Female Aedes mosquito and people: Usually classed as parasitism (+/−): the mosquito gets blood for eggs, people can catch diseases; ecologists also call mosquitoes micropredators
Mistletoe and tree: Parasitism (+/−): the mistletoe gains, the tree is harmed

Activity 2

Explain the difference between mutualism, commensalism and parasitism in your own words. — Mutualism: both gain. Commensalism: one gains, the other is unaffected. Parasitism: one gains, the other is harmed.
Why is an orchid growing on a tree not a parasite? — Epiphytic orchids take no nutrients directly from the tree; they only grow on it.
What does the clownfish get, and what does the sea anemone get, from their relationship? — The clownfish is protected by the anemone's stinging tentacles. The anemone is guarded from its predators by the clownfish.
Your friend says, "Buffalo and mynas are definitely mutualists." How would you respond? — It is only true if the birds are shown to reduce the buffalo's parasites. The documented example, the cattle egret, mainly eats insects disturbed by the buffalo, so it is usually classed as commensalism; it becomes mutualism only if the egret eats ticks off the buffalo's hide.
How is predation different from parasitism? — In predation a predator hunts and eats its prey. In parasitism a parasite lives with its host for a long time and benefits at the host's expense.

Sources and updates

2026-10-02

PanduanHewan.org · May be copied for non-commercial teaching with attribution.

https://panduanhewan.org/en/learn/symbiosis-mutualism-commensalism-parasitism/