Transcript CHARACTERISTICS OF LIVING THINGS

CHARACTERISTICS
OF LIVING THINGS
What characteristics are observed to
determine if something is “alive”?
All living things are organized.
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The cell is the basic unit
of organization.
Organelles → cells →
tissues → organs →
organ systems →
organism
Organization Continued
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Species→Population→Community→Ecosystem→Biome→
Biosphere
Species – group of similar organisms that can interbreed and
produce fertile offspring
Population – same species in same area sharing same
resources
Community – different populations in same area sharing
same resources
Ecosystem – Community plus environment
Biome – ecosystems with same climax community
Biosphere – layer of Earth that supports life (air, land, and
water)
All living things reproduce
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Reproduction is not necessary for survival of
an individual, but is essential for continuation
of a species.
The 2 main types of reproduction are sexual
and asexual.
Sexual – two parent organisms combine
genetic material to produce the offspring.
Continued:
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Asexual – a single
organism can divide or
“bud” to create
offspring which are
identical clones to the
parent (identical genetic
information).
Living things grow and develop.
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Growth refers to an
increase in size and
formation of new
structures.
Development refers to
changes during the
lifetime of an organism
(including cell
differentiation, organ
development, and aging
& death).
Cell Differentiation
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Cell differentiation
allows different cells
to perform different
functions for the
organism; it allows
for specialization.
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Examples:
Nerve cells (neurons)
Bone cells
(osteocytes)
Muscle cells
Blood cells
Living things respond to their
environment.
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Living things respond or
react to their
environment in some
way.
A stimulus is any
condition in an
environment that
requires an organism to
respond.
A stimulus can be
internal or external.
Living things maintain homeostasis.
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Homeostasis is the
regulation of a stable
internal environment so
life can continue.
Examples include
shivering when cold or
sweating when hot.
Living things obtain and use energy.
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Energy is used for
growth, development,
and reproduction.
Metabolism is the sum
of all the chemical
reactions through which
an organism carries out
its life processes.
Living things adapt and evolve.
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Adaptation – any
structure, behavior, or
process that enables an
organism to better
survive in its
environment.
Evolution – the gradual
accumulation of
adaptations over a long
period of time