Transcript living things

Living Things
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What are living things like?
• Any living thing is called an organism.
• Organisms vary in size - from the microscopic
bacteria in mud puddles to gigantic oak trees and are found just
about everywhere.
Living Things
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All living things:
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Have a cellular organization
Contain similar chemicals
Use energy
Grow and develop
Respond to their surroundings
Reproduce
Living Things
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Living Things Are Organized
• A cell is the smallest unit of an organism
that carries on the functions of life.
• Some organisms are composed of just one cell
while others are
composed of many
cells.
Living Things
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Living Things Use Energy
• The energy used by most organisms comes
either directly or indirectly from the Sun.
• Plants and some other organisms use the
Sun’s energy, carbon dioxide, and water to
make food.
Living Things
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Living Things Grow and Develop
• Organisms change as they grow.
• All of the changes that take place during the
life of an organism is called development.
Living Things
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Living Things Respond
• Living things must interact with their
surroundings.
• Anything that causes some change in an
organism is a stimulus.
• The reaction to a stimulus is a response.
Living Things
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Living Things Reproduce
• All living things eventually reproduce, to
make more of their own kind.
• Some bacteria reproduce every 20 minutes,
while it might take a pine tree two years to
produce seeds.
• Without reproduction,
there would be no
living things to
replace those
individuals that die.
How are living things classified?
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Why classify?
• Biologists use classification to organize living
things into groups so that the organisms are
easier to study.
• Organisms are grouped by their shared
characteristics.
How are living things classified?
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Classification
• Carolus Linnaeus, a Swedish naturalist,
developed a new system of grouping
organisms that was accepted and used by
most scientists.
• His classification system was based on
looking for organisms with similar structures.
• Linnaeus also developed a scientific naming
system that is still used today.
How are living things classified?
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7 Levels of Classification
Kingdom
Phylum
Class
Order
Family
Genus
Species
King
Phillip
Can
Offer
Free
Gardening
Services
How are living things classified?
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Modern
Classification
How are living things classified?
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Scientific Names
• The two-word naming system that Linnaeus
used to name organisms is called binomial
nomenclature.
• This two-word name is an organism’s species.
All living things have a scientific name.
How are living things classified?
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Binomial Nomenclature
• The first word of the
scientific name identifies the
genus of the organism. A
genus is a group of similar
species.
• The second word of the name
usually describes a feature.
Ambystoma
genus
tigrinum
feature
Ambystoma tigrinum
(Tiger Salamander)
Quercus nigra
(Water Oak)
How are living things classified?
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Why Use Scientific Names?
 they help avoid mistakes.
 organisms with similar evolutionary histories
are classified together.
 scientific names give descriptive information
about the species.
 scientific names allow information about
organisms to be organized easily and
efficiently.
How are living things classified?
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How are Living Things Grouped
Into Kingdoms?
• Type of cells (prokaryote or eukaryote)
• Number of cells in their bodies
(multicellular or unicellular).
• Ability to make food (autotroph or
heterotroph)
How are living things classified?
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Type of Cells
Prokaryote – Organisms whose cells
lack a nucleus.
Eukaryote – Organisms whose cells
contain a nucleus
How are living things classified?
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Number of Cells in Their Bodies
Unicellular – Organisms with only one cell.
Single-celled organism
Multicellular – Organisms that are composed
of many cells.
How are living things classified?
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Ability to Make Food
Heterotroph Autotroph – Organism that
makes its own food. Autotrophs
use the food they make as an
energy source to carry out their
life functions.
Organism that cannot
make its own food.
Heterotrophs need an
outside source to obtain
energy.
How are living things classified?
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Obtaining Energy
Respiration – Process by which cells
break down food to release its energy.
Photosynthesis – Process by which
plants make food. Uses light, CO2, and
water to produce sugar. Oxygen is a byproduct.
CO2
+
(Carbon dioxide)
light energy
H 2O
→
C6H12O6
(water)
(sugar)
+
O2
(oxygen)
How are living things classified?
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Reproduction
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Sexual reproduction – The reproductive
process that involves two parents who
combine their genetic material to
produce a new organism, which differs
from both parents.
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Asexual reproduction – The
reproductive process that involves only
one parent and produces offspring that
are identical to the parent.
PROTIST
BACTERIA
The 5 Kingdoms
FUNGI
PLANT
ANIMAL
Bacteria
Split into two Kingdoms
Archaebacteria and Eubacteria.
– Archaebacteria –
“ancient” bacteria found
in extreme
temperatures. They
were here before
eubacteria.
– Eubacteria – Although
some are harmful, most
eubacteria are helpful.
They provide vitamins
and yogurt.
Bacteria
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Prokaryotes – have no nucleus
Unicellular – single celled
Autotrophs and Heterotrophs
Examples:
Streptococcus (strep throat)
Staphylococcus (Staph infection)
Protists
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Eukaryotes – have a nucleus
Unicellular or multicellular
Heterotrophs and Autotrophs
3 main types: Protozoans, slime molds, and algae
DIVERSE – these organisms cannot fit into another
kingdom.
Seaweed
Fungi
• Eukaryotes
• Multicellular
(only yeast is unicellular)
• Heterotrophs
• Examples: mushrooms, yeast, mold, mildew,
athlete’s foot, ringworm, penicillin
Plants
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Eukaryotes
Multicellular
Autotrophs
Examples: trees, vegetable
plants, roses, vines
Animals
• Eukaryotes
• Multicellular
• Heterotrophs