CHARACTERISTICSOF LIVING

ORGANISMS

Identify the 7 CharacteristicsExplain the meaning of each characteristic using scientific examplesApply knowledge of characteristics to research project

1. Organization & CellsOrganization: Degree of order within an organism’s internal and external structure & how it interacts with the environment.Cells: Smallest unit that can perform all life’s processes. 1. Unicellular= 1 cell (bacteria)2. Multicellular= Multiple cells (trees, fish, you) a. Levels of Organization:Atom Molecule Organelle Cell Tissue Organ Organ System Organism Ex. ) Oxygen Phospholipid biomolecule) mitochondrion nerve cell nervous tissue with ear owl’s ear sensory barn owl

2. Response to Stimulus •A physical or

chemical change in the internal or external environment.Examples:1. Dilating eyes in response to change in light. Owl dilates pupils to keep level of light entering the eye constant.2. Pulling hand away after touching hot stove.3. Sneezing in response to dust or allergies.4. Leaves changing colors during Fall.

3. HomeostasisDefinition: Maintaining a stable

internal environment even when environmental conditions change.

• Example: Your body temperature is maintained at approximately 98°F. When your body heats up, your sweat glands secrete water to cool your skin. When you are cold, your body constricts the skin (goosebumps) to conserve heat. How would an owl maintain its body temperature at 104°F?

4. MetabolismDefinition: Sum of all chemical

reactions that involve taking in and transforming energy & materials from the environment.

• Purpose of metabolism is for obtaining energy for repair, movement, and growth.

• Example: Plants, algae, and bacteria use the sun’s energy to generate sugar (food) through photosynthesis. You depend on other organisms to obtain energy.

5. Growth & 5. Growth & DevelopmentDevelopment• All living things grow and increase

in size by the cells dividing and enlarging.

a. Unicellular organisms- Cell division then enlargement.

b. Multicellular organisms- Mature through cell divison, enlargement, and development.

Development: Process by which an organism becomes a mature adult through cell division & cell specialization.

6. Reproduction• Production of new organisms like

themselves.• Reproduction, unlike the other 6

characteristics, is not essential to the survival of an individual organism. It is essential for the survival of the species.

• During reproduction, organisms pass on hereditary information (DNA) to their offspring.

• Sexual: hereditary information is combined from 2 organisms of the same species.

• Asexual: hereditary information from different organisms is not combined ~ the original organism and new organism are genetically the same. Ex) bacteria

Observe the changes below:

7. Change Through Time• Although individual organisms

experience changes during their lifetime, their basic

• genetic characteristics do not change.

• Populations of living organisms evolve or change over long periods of time in order to survive in a changing world.

Example: Peppered Moth