Characteristics of Life

Characteristics of Life
Living things are made of 1 or more cells
1. All are composed of cells
a. Cells are the basic units of life
Living things are organized
1.cells work together to form increasingly higher levels of
b. cells – tissues – orgasm – systems – individuals –
populations – communities – ecosystems – biosphere
Living things metabolize
1. metabolism is the sum of all of the chemical and energy
transformations that take place in an organism
2. such conversions are required if an organism is to maintain itself
Living things grow
1. sometime in every organisms life
a. even single-cell organisms
b. involves conversion of materials from the environment into
components of organism
c. may involve mitosis
Living things respond
1. homeostasis – is the maintenance of internal conditions within
certain ranges.
2. organisms react to the presence of appropriate stimuli
a. physiologically
b. behaviorally
Living things reproduce
1. all living things come from other living things
2. living things make copies of themselves
3. to do so they pass on genes(sections of DNA molecules that
contain instructions for organization& metabolism)