Transcript Organisms

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Make a list of life activities of a pond
organism that can only be seen under a
microscope.
Make a list of the life activities of a fish.
Which organism do you think can adapt to a
wider range of conditions? Why?
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You are a many-celled organism because your
body is made up of more than one cell.
 Human body is made of more than a trillion cells
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There are single-celled organisms such as an
amoeba, that has only one cell.
 Can only be seen with a microscope
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In many-celled organisms, cells are specialized
to perform different tasks in the body
They must be organized to work together and
keep the organism healthy
5 main levels of organization
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Cells
Tissues
Organs
Organ systems
Organisms
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In many-celled organisms, cells perform
many different functions.
These cells are specialized; that is, different
types of cells that do different kinds of work
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Each group of specialized cells is organized
into tissues
 Muscle cells make up three different kinds of
muscle tissue in the human body: smooth,
skeletal, and cardiac.
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Tissues are organized into groups called organs
An organ is a group of tissues that work together
to perform special functions.
Both plants and animals have tissues and
organs.
A heart is one of many organs in a
many-celled organism
 Heart is mostly made of cardiac
muscle tissue
 Also contains nerve and connective tissues
▪ Muscle, nerve, and connective tissues work together to pump
blood through the heart and body
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A group of organs that work together make
up an organ system
Some organisms, such as sponges, have no
organ systems
Some organisms, such as flatworms, have
only a couple organ systems
Complex organisms, such as dogs and
humans, have ten organ systems
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Highest level of cellular organization
All organisms carry out life processes
In most organisms, the different organ
systems work together to keep the organism
alive
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Circulatory: pump blood throughout the body
Skeletal: enables support, protect, and movement
Muscular: enables support, protect, and movement
Skin: protects organism from the outside environment
Endocrine: deals with hormones in the body
Reproductive: enables organisms produce more
organisms like themselves
Digestive: enables you to process the nutrients your body
needs
Respiratory: enables you to breathe
Excretory: removes waste
Nervous: receives and sends electrical and chemical
signals
List at least one example of each of the following: cell,
tissue, organ, organ system, and organism.
 Describe the difference between a cardiac muscle cell,
cardiac muscle tissue, and the heart.
 Can a single-celled organism contain tissue?
EXPLAIN.
 Classify the following as a tissue, organ, or organ
system:
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Brain
Spinal cord
Nerves
Heart
Group of muscle cells