Transcript Its Alive * or is it?

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Its Alive – or is it?
The Characteristics of Life
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I can…
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Describe the biological criteria that need to be met in order
for an organism to be considered alive
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6 Characteristics of Life
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In order for ANY organism, no matter how large or small, to
be considered alive, it must exhibit the following 5
characteristics:
1.
Organization
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Ability to acquire materials and energy
3.
Ability to maintain homeostasis
4.
Ability to respond
5.
Ability to reproduce and grow
6.
Acquire adaptations
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Organization within a living
organism…
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Organization of living things begins with atoms, which make up
basic building blocks called elements and molecules
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The cell is made up of molecules and is the basic structural and
functional unit of all living things
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Different cells combine to make up tissues
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Tissues combine to make up an organ
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Specific organs work together as an organ system
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Multicellular organisms contain organ systems
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Each level of organization is more complex that the level
preceding
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Working with what we have
learned…
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Make flow chart of the levels of organization – within an
organism
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At each level, give at least 2 examples
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Organization between living
organisms…
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A species is the same type of organism
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A population is group of the same species in a particular
area
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Interacting populations in a particular area is a community
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A community PLUS its physical (non-living) environment is an
ecosystem
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The biosphere is comprised of regions of the Earth’s crust,
waters and atmosphere inhabited by organisms
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Working with what we have
learned…
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Using our classroom as our “particular area”, give examples
for each level of organization found between organisms
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Acquire Materials and Energy
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Maintaining organization and conducting life-sustaining
processes require an outside source of energy
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The ultimate source of energy for nearly all live on earth is the
sum
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Plants and certain other organisms convert solar energy into
chemical energy by the process of photosynthesis
Metabolism is all the chemical reactions that occur in the cell
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Ability to maintain homeostasis…
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All organisms must maintain a state of biological balance, or
homeostasis
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Temperature, moisture level, pH level, etc.. Must be maintained
within the tolerance range of the organism
Organisms have intricate feedback and control mechanisms
to maintain homeostatic balance
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Ability to Respond…
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Living things interact with the environment and with other
living things and need to respond accordingly
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Response often results in movement of the organism
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A plant bending toward the sun to capture solar energy or a turtle
withdrawing into its shell for safety
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Responses help ensure survival of the organism and allow
the organism to carry out biological activities
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The collective responses of an organism constitute the
behavior of the organism
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Ability to reproduce and grow…
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Reproduction is the ability of every type of organism to give
rise to another organism like itself
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Bacteria, protozoans, and other unicellular organisms simply split
in two (binary fission) – asexual reproduction
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Multicellular organism often unite sperm and egg, each from a
different individual, resulting in an immature individual which
develops into the adult – sexual reproduction
The instructions for an organism’s organization and
development are encoded in genes
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Genes are comprised of long molecules of DNA
(Deoxyribonucleic acid)
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DNA is the genetic code for all living things
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Acquire to Adaptations…
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Adaptations are modifications that make organisms suited to
their way of life
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Occur over a long period of time
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