Transcript What Is Life - lpeaks7thscience

What Is Life?
Chapter 1
Characteristics of Living
Things
Life Comes From Life
Needs of Living Things
Living, Non-living & Dead
Characteristics of
Living Things: All
living things…
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Are made of
cells.
Have the
Chemicals of
Life.
Use Energy.
Are able to
grow and
develop.
Will respond
to a stimulus.
Are able to
reproduce.
Cellular Organization
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Cells: The basic unit of
structure and function in an
organism.
Organism: A living thing that
shares all of the
characteristics of living
things.
Unicellular: single celled
organisms (bacteria)
Multicellular: Many celled
organisms
Chemicals of Life
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Water (most abundant)
Carbohydrates (energy
source)
Proteins & Lipids (building
materials)
Nucleic Acids (genetic
material)
Carbohydrates:
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The main source of energy
for living things.
Sugar and starch
Fruits
Proteins:
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Eggs, meat, fish, beans, nuts
and poultry.
Made up of Amino Acids.
Needed for the growth and
repair of body structures.
Hair and muscles.
Provide energy.
Nucleic Acids:
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The blue prints of organic
chemicals.
Large compounds.
Help to make proteins.
DNA and RNA are Nucleic
Acids.
Energy Use:
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Metabolism: The chemical
reactions performed by a
living organism. Needed for
growth, to store energy, and
repair cells.
Ingestion: How a living thing
takes in or produces food.
Digestion: The process of
breaking down food into
simpler substances.
Energy continued:
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Respiration: The process of a
living thing taking in food to
produce energy.
Excretion: The removal of
waste products.
Response:
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Stimulus, (Stimuli: plural):
The signals to which an
organism reacts.
Response: The action or
movement or change caused
by a stimulus.
Growth &
Development
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Growth: the process of
becoming larger.
Development: the process of
change that occurs during an
organism’s life to produce a
more complex organism.
Reproduction:
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Sexual Reproduction:
requires two parents. Most
multicellular organisms
reproduce this way.
Asexual Reproduction:
reproduce with only one
parent. Bacteria, yeast and
some plants reproduce this
way.
Changing an old
theory:
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Spontaneous Generation:
Before the 1600’s people
believed that life could spring
from non-living things.
Francesco Redi: an Italian
doctor in 1668 helped to
disprove Spontaneous
Generation.
Louis Pasteur
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Mid-1800’s
French Chemist
Proved that Spontaneous
Generation was not true.
He compared bacterial
growth in boiled and unboiled broth.
Pasteurization
Needs of Living
Things:
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Food
Water
Living Space
Stable Internal Conditions
Food
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Autotroph: a kind of living
thing that can make it’s own
food. Auto means “self” and
troph means “feeder”.
Heterotrophs: a kind of living
thing that cannot make their
own food. Hetero means
“other”. They must obtain
energy by feeding on others.
Stable Internal
Conditions
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Homeostasis: To maintain a
stable internal condition.
Organisms must be able to
keep the conditions inside
their bodies stable, even
when conditions in the
surroundings change.
Living Things:
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Have all 6 characteristics of
living things or have the
potential to (seeds).
Cells
Chemicals of Life
Use Energy
Respond to their
surroundings
Grow and Develop
Reproduce
Non-living Things:
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Do not have all of the 6
Characteristics of living
things. It may have some,
but not all!
It may never have been alive
(rock), OR
It may have been alive once
(tree), but went through a
chemical or physical process
and was changed (chair).
Dead:
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It once was alive, but no
longer is.
It may still have cells or
chemicals of life, but they no
longer function.
The End
Created by Mrs. Scibelli
Science Explorer From
Bacteria to Plants