1. Relationships Among Organisms Biology EOCT Review

2. Habitats and Niches  Habitat : the place where an organism lives (WHERE)  Forest is a common habitat for squirrels  Many species of organisms can share the same habitat  The resources (food, water, and shelter) that a habitat provides can be divided into different niches.  Niche : an organism’s role in its community; include what it eats, where it is in the food change, where it feeds (HOW)

3. Habitats and Niches

4. Symbiosis  Symbiosis is an interdependent relationship between organisms of two different species. The three types of symbiosis are: mutualism, commensalism, and parasitism.  Mutualism : symbiotic relationship where both species benefit  Example: Sea anemones (+) and clownfish (+)

5. Symbiosis  Commensalism : a symbiotic relationship in which one organism benefits and the other neither benefits nor is harmed  Example: Remora (+) and sharks (0)  Parasitism : a symbiotic relationship in which one organism benefits and the other organism is harmed  Example: tapeworms (+) and dogs (-)

6. Predation  Predation : an interaction in which one organism kills and eats another  Predator/prey relationship cause population cycles  The organism that gets the food is the predator  The organism that is killed and eaten is called the prey

7. Competition  Competition : is an interaction in which two or more organisms try to use the same resources  Competition can occur within species (intraspecific competition) or between different species (interspecific competition)