WARM UP 8/29/14 True or False? – answer in notebook If it moves it is alive If it seems to move by itself, it’s alive; if it’s moved by something else, it’s not alive. If it makes light or noise it is alive It’s not alive unless it is doing something To be alive, it must breathe Not all living things grow Bacteria and fungi are not living things Plants have a completely different kind of life than animals

Characteristics of Living Things What is Life? Define life? Is this a living thing? an organism? Origin?... Spontaneous generation/abiogensis or biogenesis?

No one definitive list: Organized Reproduce Responds to stimuli Requires water and energy Adaptation Grow and Develop Maintain homeostasis

Organization One or more cells –unicellular, multicellular Cells contain DNA molecules = heredity Common set of compounds –organic molecules = carbon & hydrogen Simple to complex – at all levels Maintain and repair structure organs organ systems tissues organisms cells populations compounds communities molecules ecosystems atoms biosphere

Reproduction Marks a successful life Continues the species Group of organisms that can interbreed and produce fertile offspring Pass on genes / DNA Sexual and/or asexual

Respond to stimuli Possess “irritability” – able to respond Stimulus must be strong enough to elicit a response Must respond to environmental stimuli to survive and/or reproduce Homeostasis – maintain internal conditions or environment By internal feedback systems – communicate

ENERGY REQUIRED Ultimate source is the sun To maintain other characteristics and stay alive; Must be obtained – ingested or absorbed; converted to a usable form May be transformed and transferred but never created or destroyed Respiration – exchange gases with environment Require water for chemical reactions METABOLISM –sum of all chemical reactions and energy exchange within an organism Anabolic reactions – build up; simple >> complex Catabolic reactions – break down; complex >> simple

Change over time Growth – increase in size Develop – change in abilities; + / - Die – limited lifespans

Adaptation Inherited structure, behavior or internal process that enables organism to respond to environmental factors and live successfully Only an adaptation if inheritable Must match environment Gradual accumulation of adaptations result in evolution Result of mutation – not intentional Must be able to be passed along Able to move in some manner to meet needs

All living things… Have every characteristic at some time in their life Similar in the variety of processes they carry out May be in a state of dormancy Individual does not have to reproduce to survive – but species must!