LOOKING INSIDE CELLS
Chapter 4, Section 3
6th Grade Text
TYPE OF CELLS
• PROKARYOTES – Cells that have a cell wall
and cell membrane but lack an organized
nucleus. Example is bacteria cell.
TYPE OF CELLS
• EUKARYOTES – Cells that contain a defined
nucleus and a variety of organelles.
Examples are animal cells and plant cells.
ANIMAL CELLS
• Animal cells (and plant and bacteria cells) contain within them tiny cell
structures call organelles that carry out specific functions within the cell.
Examples of organelles are ribosomes, mitochondria, and endoplasmic
reticulum.
organelles
• is a specialized subunit within a cell that has a
specific function, and is usually separately
enclosed within its own lipid bilayer.
CELL MEMBRANE
For animal cells, the cell membrane forms the outside boundary that separates
the cell from its environment. Its structure is essentially a double layer of fat
with embedded proteins. Its main function is to control what substances
come into and out of the cell.
CELL MEMBRANE
Draw the Nucleus and label it!
NUCLEUS
• The nucleus is a large oval
structure that acts as the
“brain” of the cell,
controlling all of the cell’s
activities.
• It is made up of the nuclear
membrane, chromatin and
nucleolus.
NUCLEAR MEMBRANE
• The nuclear membrane,
like the cell membrane,
is essentially a double
layer of fat.
• It’s function is to
protect the nucleus, and
to allow materials to
pass in and out of the
nucleus through small
openings (pores) in the
membrane.
chromatin
• Contains in the nucleus
• consisting of long
strands of DNA (nucleic
acid). When the cell is
in resting stage, the
chromatin is relaxed
and when the cell is
going to divide,
chromatin condenses
and forms what is
known as
“chromosome”during
cell division
CHROMOSOMES
• The nucleus contains thin strands of genetic material called chromatin.
When the cell begins to divide, the chromatin strands coil and condense to
form structures called chromosomes.
NUCLEOLUS
• a non-membrane bound
structure found inside
the nucleus.
• Function made
ribosomes.
CYTOPLASM
• Is a thick, clear, gellike fluid found
between the cell
membrane and the
nucleus.
• Most cell activities take
place in the cytoplasm
• Is where the Cell
organelles are found
“floating” in the
cytoplasm.
MITOCHONDRIA
• rod-shaped organelles
called the “power-houses”
• produce most of the
energy the cell needs to
carry out its functions.
• Muscle cells and other
very active cells have
large numbers (1000s) of
mitochondria. Less active
cells might have only one
mitochondria.
ENDOPLASMIC RETICULUM
• Is a maze of
passageways
• Function carry proteins
and other materials from
one part of the cell to
another.
Smooth ENDOPLASMIC
RETICULUM
• Is smooth… no presence of
ribosomes.
• is involved in lipid synthesis and
steroid synthesis.
• It is also involved in drug
detoxification.
Rough ENDOPLASMIC RETICULUM
• surface of the
membrane of RER is
studded with ribosomes
(another type of
organelle)
• function of RER is the
synthesis and
manufacture of
proteins.
RIBOSOMES
• Ribosomes are small,
grain-like bodies either
attached to the
endoplasmic reticulum or
free floating in the
cytoplasm.
• Ribosomes are factories
that produce proteins.
• These proteins are passed
to the ER, then transported
to the Golgi Bodies.
RIBOSOMES
GOLGI BODIES
• structures that look like a
flattened collection of sacs
and tubes that serve as the
cells “mail-room”.
• Function: receive proteins
from the ER, package them,
and deliver them either to
other parts of the cells, or
release them outside the cell.
GOLGI BODIES
LYSOSOMES
• small, round, membrane
enclosed.
• Functions: break down
food particles and old cell
parts. Then the
substances released can
be recycled and used to
build new parts.
VACUOLES
• membrane-bound organelles
• Functions: store water, food, and other materials needed by
the cells but they can also contain waste products.
• Vacuoles are more prominent in plant cells, and typically
occupy more than 30% (and up to 80%) of a plant cell’s
volume.
LYSOSOMES & VACUOLES
Cells organelles song
• Mr. W cells song with all the animal cell
organelles
PLANT CELLS
PLANT CELLS
CELL WALL
• The cell wall is a rigid
layer of non-living
material that surrounds the
cells of plants. It is made
of a tough, flexible
material called cellulose
(Wood contains lots of
cellulose.) The cell wall
functions to protect and
support the cell.
CHLOROPLASTS
• Chloroplasts are large green organelles that function to capture
energy from sunlight and use it to produce food for the cell.
Remember: 6CO2 + 6H2O  C6H12O6 + 6O2
• Mr. W cells song with all the animal cell
organelles and plants
• cell rap
• Interactive cells