Biology A&P / Ecology Unit

Organization of Life Life is organized from the simplest form to very complex Cells, tissues, organs, organ systems, organisms, populations, community, ecosystem, biome and biosphere

Tissues A group of cells working together to perform a function.

Organs A group of tissues, working together to perform a function.

Organ Systems A group of organs working together to perform a function.

Organisms A group of organ systems working together to maintain a creature capable of performing all seven characteristics of life.

Population All of the members of a species in a specific area. A species is a group of organisms that look similar and can produce fertile offspring.

Community All of the organisms in a specific area.

Ecosystem All of the living and non-living things in an area. Biotic – the living part of an ecosystem Abiotic – the non-living part of an ecosystem

Biome An area of earth with similar climate and geography and organisms adapted to live there.

Biosphere The part of the earth where life is found.

Organism Relationships Organisms often have a variety of ways they can interact with one another in their particular ecosystem.

Predation One organism eats another. One organism benefits, the other is harmed.

Competition Two organisms compete for a limited resource. Both organisms are adversely affected.

Parasitism One organism benefits, while the other is adversely affected.

Mutualism Two organisms live together and both benefit.

Commensalism Two organisms live together, one benefits while the other is not affected.

Nutrient Cycles Several nutrients need to be cycled through ecosystems. These include water, carbon, nitrogen and oxygen.

Ecosystem Response Changes in climate, the introduction of non-native species, pollution and fires can cause changes to ecosystems. Some changes are positive, while others are negative.

Limiting Factors Anything that limits the size of a population. Examples are food, water, shelter or specific habitat requirements.

Carrying Capacity The maximum population of a species an ecosystem can support for a long period of time.

Limiting Factors Potential Effects If a limiting factor becomes scarce on a global level, the end result could be extinction.

Symmetry When parts of something are roughly mirror images of themselves. You can draw a line of symmetry showing where this occurs.

Bilateral Symmetry Only one line of symmetry can be drawn.

Radial Symmetry Many lines of symmetry can be drawn in only one plane.

Spherical Symmetry Many lines of symmetry can be drawn in many planes.

Asymmetry No lines of symmetry can be drawn.

Asexual Reproduction Organisms that reproduce without exchanging genes. They are clones of the original organism. EX: binary fission in bacteria or budding in some animals

Sexual Reproduction When organisms exchange genes during reproduction. It creates a new combination of genes. EX: most plants and animals

Anatomy and Physiology Anatomy – the study of the structures of something. Physiology – the study of the functions of structures. Different organisms have different structures for surviving in their ecosystem.

Earthworms

Sea Star

Fish (Perch)

Frog