Is it Alive?

Six Characteristics of Living things All living things have cells. A cell is the smallest unit of life. It is a membrane covered structure that holds all the materials necessary for life. Some organisms are made up of just one cell; others made up of trillions Different cells perform different specialized jobs (nerve cell / skeletal cell)

Six Characteristics of Living things 2. Living things sense and respond to change Stimulus: anything that causes a reaction or change in an organism Examples: chemicals, gravity, light, sounds, hunger Homeostasis: the maintenance of a constant internal state in a changing environment Examples: temperature regulation (shivering to warm you up and sweating to cool you down)

Six Characteristics of Living things Living things reproduce Organisms produce offspring similar to themselves Sexual reproduction: sex cells from 2 parents unite; offspring share traits from both Asexual reproduction: one parent produces offspring identical to itself (bacteria; hydra)

Six Characteristics of Living things Living things have DNA Deoxyribonucleic acid Controls the structure & function of cells DNA is passed to offspring, ensuring that they resemble parents Heredity: the passing of traits from parent to offspring

Six Characteristics Living things use energy Organisms use energy to carry out life’s activities Include: making food, digesting food, moving materials into and out of cells, building of new cells Metabolism: the total of all of the chemical activities that an organism performs

Six Characteristics of Living things Living things grow and develop

Life’s Basic Needs Water (70% of a living organism IS water)

Life’s Basic Needs Water (70% of a living organism IS water) Air (made up of several different gases, including oxygen and carbon dioxide)

A place to Live Life’s Basic Needs Water (70% of a living organism IS water) Air (made up of several different gases, including oxygen and carbon dioxide) A place to Live

Life’s Basic Needs 4. Food Producers: make their own food (plants) Consumers: eat other organisms to get food (us) Decomposers: get food by breaking down nutrients in dead organisms (mushroom)