Download Relationships among organisms

Biology
Class Notes
Lesson 16 Relationships among Organisms
Objective: 2.1.3
Population: All the organisms of a species that live in the same area at the same time.
Stable Ecosystem: One in which the population sizes and available resources cycle regularly or change
predictably.
Illustrate curve of stable population.
Habitat: The place where an organism lives.
Niche: An organism’s role in a community.
Insert “On Beyond Zebra Quote”
Interactions of Organisms
Predation: An interaction between organisms in which one kills and eats another.
Predator = killer
Prey = victim
Competition: An interaction in which two or more organisms try to use the same resources at the same time.
Symbiosis: A close interdependent relationship between organisms of different species.
Mutualism: A symbiotic relationship in which both organisms benefit because each species does something
that helps the other species survive.
Commensalism: A symbiotic relationship in which one organism benefits and the other does not seem to
benefit or be harmed.
Parasitism: A symbiotic relationship in which one organism benefits and the other is harmed.
Communication and Defense of Territory
Territory: An area an animal claims and defends to ensure it has access to resources it needs for survival.
Methods:
Body language
Calls
Markings
Pheromone: A chemical substance that an animal produces to create a specific response in other animals of the
same species.
Key Words:
Population
Stable ecosystem
Habitat
Niche
Symbiosis
Mutualism
Commensalism
Parasitism
Predation
Competition
Pheromone
Territory