Characteristics of LifeCharacteristics of Life

ObjectivesObjectives

• List six characteristics of life• Describe how a living thing is

organized• Explain why all living things

on Earth are not yet well understood

The Characteristics of Life

The Characteristics of Life

How can you tell if something is alive?

The Characteristics of Life

The Characteristics of Life

• Biologists have devised a list of 6 characteristics that define life.

• Something can be considered alive ONLY if it displays ALL 6 of the characteristics.

Anything that possesses all 6 of the characteristics of life is called an organism.

• 1. Made up of Cell(s)

• 2. Cellular Organization celltissueorgansystemorganism

• 3. Growth & Development• 4. Reproduction• 5. Adaptation to environment

– response to a stimulus

• 6. Maintaining Homeostasis

The 6 characteristics of life:

1. Cells1. Cells

• Basic unit of life

• All living things are made up of one or more cells

• Cells are made up of smaller parts called organelles

2. Cellular Organization2. Cellular Organization

• Cell -> Tissue -> Organ -> Organ System -> Organism

• Specific parts of cells (organelles) carry out different functions

3. Growth & Development3. Growth & Development

• All living organisms grow and develop during their life spans.

• Growth: an increase in the size of an organism due to an increase in the size and number of cells

• Development: all of the changes that take place throughout the life span of an organism

4. Reproduction4. Reproduction

All living organisms are able to produce live offspring.

• Species produce offspring similar to themselves

• NOT essential of the survival of an individual organism

• Essential for continuation of the species

• All living organisms are able to adapt to their surroundings.

• They are able to react, or respond to an environmental condition, or stimulus.

5. Adaptation to Environment:5. Adaptation to Environment:

6. Homeostasis6. Homeostasis• All living organisms are able to maintain a

relatively constant internal environment. • Homeostasis: Maintain a constant stable

internal environment suitable for life

• When an organisms is unable to maintain homeostasis it dies

• Metabolism provides the raw materials and energy to maintain homeostasis Metabolism: sum of all the chemical reactions that

occur in the organism

The Living WorldThe Living World

• World of biology is rich with organisms and diverse with different types of life yet many organism have yet to be discovered this and more will be discussed in classification.

Fun Facts about Organisms Fun Facts about Organisms

• Largest Animal Alive Today Blue Whale

• 30 meters in length = 120 feet• weigh up to 130 metric tons (= 30 elephants)

• Largest Plant Alive Today Giant Sequoia Tree

• height over 100 meters = 300 feet

More Fun FactsMore Fun Facts

• Smallest Living Things Bacteria

• As small as 1000 nanometers in length

• Viruses 100 times smaller than bacteria but can’t be

classified as an organism. Are viruses alive?