The Nature of Life Chapter 2

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Transcript The Nature of Life Chapter 2

What Is Life?
Characteristics of Living
Things
Life Comes From Life
Needs of Living Things
Living, Non-living & Dead
Life:
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the condition that
distinguishes animals and
plants from inorganic matter,
including the capacity for
growth, reproduction,
functional activity, and
continual change preceding
death.
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, protist)
Multicellular: Many celled
organisms
Chemicals of Life
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Water (most abundant)
Carbohydrates (main energy
source)
Proteins & Lipids (building
materials, energy sources)
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
using food to produce
energy. (mitochondria)
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
Edited by Coach Si