Page 88 - Science Course 3 (Book 1)

Mo2-L6a:How Living Organisms Interact?

Key Concept Types of Symbiotic Relationships

How Living Organisms Interact? Mutualism—two species in a community benefit
from the relationship.
How do the different population in lake interaction
with each other? Parasitism—one species (the parasite) benefits
while another (the host) is harmed.

Commensalism—one species benefits and the
other is neither helped nor harmed.

Let’s Begin

Key Concept
Symbiotic Relationships How Living Organisms Interact?

Each population has different ways to stay What is one example of a symbiotic relationship?
alive and reproduce.

All of the populations in a community share a
habitat, the physical place where a population or
organism lives.

A niche is the unique ways an organism survives,
obtains food and shelter, and avoids danger in its

Environment
• everything around where something lives or
grows.
• the air, plants, earth, water everything.
Habitat
• an area in the environment were a living thing can
grow and survive.
• forests, oceans, deserts, arctic are all examples SUMMARY
of habitat.
How Living Organisms Interact?
Niche
• the part of a habitat where a living thing makes The factors that limit the size a population of
its home organisms can reach are called limiting
factors.
A symbiotic relationship is one in which two different
species live together and interact closely over a long A habitat is the physical environment where a
period of time. population of organisms lives.

These relationships can be beneficial to both organ- A symbiotic relationship exists when two dif-
isms, beneficial to one and harmful to the other, or ferent species of organisms live together in a
beneficial to one and neutral to the other. close relationship over a long period of time.
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