Download Characteristics of Life

Characteristics of
Life
Characteristics of Life
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There is no one definition of life that is
accepted by scientists.
However, life is defined by the properties
and functions characteristic of living things
Life Functions {Properties of Life} are the
various activities carried on by living things.
Properties of Life
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Order
Reproduction
Growth and Development
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Energy Utilization
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Nutrition
Respiration
Response to Stimuli
Order
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All other characteristics of life emerge from
an organism’s complex organization
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Made up of cells
A single cell can be an organism
Bacteria
 Unicellular
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Most organisms are multicellular
Energy Utilization
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Energy is used to grow, develop and
reproduce
Anabolism
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Process in a living thing that involves putting
things together, or synthesizing complex
substances from simpler substances
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Photosynthesis
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Photo = Light
Synthesis = put together
Energy Utilization #2
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Catabolism
Changing complex substances into simpler
ones
 Results in a release of energy
 Can animals perform photosynthesis?
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Metabolism
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The total sum of all chemical reactions in the
body
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The balance of anabolism and catabolism
Growth and Development
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Growth involves the increase in cell number and
cell size
What growth spurt are you going through right
now?
When does an organism stop
growing/developing?
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What tells our body that it is time for a cell to die?
How often do humans replace every cell in their body?
Growth-->Aging-->Death
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How can you tell when a tree has died?`
Reproduction
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New cells arising from preexisting cells
Organisms can reproduce their own kind
Produce organisms of the same “type”
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Species
Sexual Reproduction
Asexual Reproduction
Plants
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Dicots
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Plants contain both sperm and eggs
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Located in the flower of the plant
Fertilization
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Self Pollination
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The sperm fertilizes the egg of the same plant
Cross Pollination
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The sperm of Plant A fertilizes the sperm of Plant B
Response to
Stimuli/Environment
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Involves behaviors, metabolism and
growth
What are some environmental pressures
that you, as a human, respond to?
Response to
Stimuli/Environment II
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Is it always hot in Florida?
What does your body do to cool off?
Response to
Stimuli/Environment III
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Homeostasis
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Process by which organisms respond to stimuli in
ways that keep their body suitable for life
Refers to an organism’s ability to maintain a constant
or stable condition
Regulation mechanism to maintain an organisms
internal environment
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Provides capacity to evolve--”micro-evolution”
What household appliance provides a great
example of homeostasis?