Download Scientific Inquiry

Looking Inside Cells
“Cell Structure”
An Overview of Cells
 Cells are the basic units of structure and function in living things.
(That means all living things are made of one or more cells!)
 Cells form the parts of an organism and carry out all of an organism’s
processes or functions.
Living things are organized!
Just like your house is part of your block,
and your block is part of Massapequa,
and Massapequa is part of New York State,
and New York State is part of the United States…..
….cells are part of larger things, which are part of larger things.
We call this “levels of organization.”
Organelles are smaller structures within each cell that perform certain
functions. Just like your stomach and brain have different functions in your body
… organelles have different jobs within the cell.
Surrounding the Cell
 Cell Membrane – forms the outer boundary
in animal cells , (located inside the cell wall
in plants)
 Cell Membrane controls what substances
go into and out of the cell… the
“gatekeeper” of the cell
 Cell Membrane is semi permeable, allowing some things to pass through but not
others (based on size)
Explain what semi permeable means and give an example of something that is semi permeable.
The “Center” of the Cell
(contains the Nucleus)
 Nucleus – a large oval structure
 Nucleus is the cell’s control center,
directing all of the cell’s activities
 Nuclear Envelope or Nuclear Membrane –
surrounds and protects the nucleus and
allows materials to pass into and out of the
nucleus through pores (tiny openings)
 Chromatin (Chromosomes) –located inside the
nucleus, these strands of genetic material:
(Genes, DNA, and Chromosomes)
contain the instructions for all the cells functions
Organelles in the Cytoplasm
 Cytoplasm – located between the cell membrane and
the nucleus
 Gel-like fluid that is always moving
 Contains many cell organelles
 Mitochondria – rod-shaped structures
 The “mighty mitochondria” are the
“powerhouses” of the cell that convert
energy in food molecules to energy that the
cell can use to carry on its functions
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


Vacuoles – are the storage areas of the cell
Vacuoles can store food ,water, or wastes
Most plant cells have one large vacuole
Some animal cells have vacuoles and others do not
Structures found ONLY in Plant Cells
 Cell Wall – this rigid (stiff) layer of nonliving material surrounds
the cells of plants and some other organisms
 Cell Wall helps to protect and support the cell
 Cell Wall is mostly made of a strong material called cellulose, but it
can let many materials like water and oxygen pass through
Describe the difference between the outside of a plant cell and the outside of an animal cell.
 Chloroplasts – large green structures found
mostly in plants
 Chloroplasts capture energy from the
sunlight and use it to produce food for the
cell
 The green enzyme chlorophyll gives plants their
green color
Check yourself … fill in the organelles
the fun
Organelle/Structure
Function / Description
Found in plant cells /supports and protects cell
Controls what goes in and out of the cell
“Control center” of the cell …directs activities of the cell
Surrounds the nucleus and controls what goes in and out
Strands of genetic material found in nucleus
The “powerhouses” of the cell /convert food to usable energy
Stores food water and wastes
Captures energy from sunlight and uses it to produce food
Gel –like fluid found throughout the cell / contains organelles
Large
Central
Vacuole
Cytoplasm
Mitochondria
Nucleus
Chloroplast
Cell wall
Cell Membrane
Mmmembrane
Compare the general shape of plant and animal cells.
Compare the size and number of vacuoles in plant and animal cells.
Why would animal cells have more mitochondria than plant cells?
Many
Small
Vacuoles
Put a check mark in the box if the structure present
Cell
Structure
cell membrane
cell wall
chloroplast
cytoplasm
mitochondria
nucleus
vacuole
Plant cells
Animal
cells
Both
Plant& Animal
Which two structures
are found only in plant
cells?
Specialized Cells
 Cells within a certain plant or
certain animal are different from
one another
 Different cells have different
functions and their structure
is determined by the job they
have
 Bone Cells have
chemicals to strengthen
them
 Nerve cells are structured
to carry messages
 Red blood cells are
structured to carry oxygen
through tiny blood vessels
Cells in your body look and function differently. Do you think they all have the same set of
instructions?
Why or why not?
Organization In Living Things (from part to whole)
In many celled organisms cells are organized into tissues, organs and organ
systems:
Organelles – are small structures that perform
jobs within the cell
Cells – are the basic units of structure and
function in living things and the smallest
structure capable of carrying on all of life’s
processes
Tissues - are groups of cells that performs a particular
function (e.g. Muscle)
Organs - are groups of tissues working together
to do a job (e.g. heart, lungs, kidneys,
brain)
Organ Systems - are made of several organs working
together to carry out a life process (e.g. Digestive System for
breaking down food)
Organisms – are made of many organ systems
working together (e.g. trees, humans, fish)
Organelles  Cells 
Tissue

Organs

Organ Systems 
Organisms
Organelles  Cells 

Tissue
Organs

Use the words above to label
the circles below!
Organ Systems 
Organisms
1 is the simplest and 6 is the
most complex!
6
5
4
3
2
1
Time to
Think!
#
1
2
3
4
5
6
Correct Organization Level Word
Tissue
Make sure to list things
from the simplest (1) to
the most complex (6)!