Why can’t you use your arm muscles to digest
An organism made of many cells.
Made by making more small cells,
not by making cells larger.
For example: Elephant vs. human
1. Larger than single celled
2. Prey for less predators
3. Wider variety of prey
1. Is not limited to the lifespan
of a single cell
1. Each cell has a specific
2. Makes organism more
Tissue-group of cells that work together to
perform a specific job.
Material around and between the cells is also
part of the tissue.
Animals have four types of tissue
1. Nerve tissue
2. Muscle tissue
3. Connective tissue
4. Protective tissue
Plants have three
types of tissue:
1. Transport tissue-
moves water and
nutrients through a
2. Protective tissue-
covers the plant;
helps the plant
3. Ground tissue-
takes place here
Organ - a
up of two or more
Has several kinds of
Muscle tissue makes food move in and
through the stomach.
Special tissues make chemicals that
help digest your food.
Connective tissue holds the stomach
Nervous tissue carries messages back
and forth between the stomach and the
Organ - a structure made up
of two or more tissues
working together to perform a
A group of organs working
together to perform a
particular function is called an
Each organ system has a
specific job to do in the body.
Plants have organ systems
Stomach and Intestines
1. Job is to break down food into small
2. The rest of the body depends on the
digestive system for fuel.
The digestive system depends on the
respiratory and cardiovascular systems for
Heart and Blood Vessels
Anything that can perform life processes by
itself is an organism.
Unicellular and multicellular
Live in colonies but all of the cells
are single cells
Each cell must carry out all life
processes to survive
Even the simplest
multicellular organism has
specialized cells that
depend on each other for
the survival of the
Holt Science and Technology. Holt, Rinehart,
and Winston. Harcourt Education Company.
Austin, Texas 2005.
UCP 1: Systems, order, and organization
UCP 2: Evidence, models, and explanation
UCP 5: Form and function
LS 1a: Living systems at all levels of organization
demonstrate the complementary nature of structure and
function. Important levels of organization for structure and
function include cells, organs, tissues, organ systems,
whole organisms, and ecosystems.
LS 1b: All organisms are composed of cells—the
fundamental unit of life. Most organisms are single cells;
other organisms, including humans, are multicellular.
LS 1d: Specialized cells perform specialized functions in
multicellular organisms. Groups of specialized cells
cooperate to form a tissue, such as a muscle. Different
tissues are in turn grouped together to form larger functional
units, called organs. Each type of cell, tissue, or organ has a
distinct structure and set of functions that serves the
organism as a whole.