Cell Structure - Mr. Dones'...
Transcript of Cell Structure - Mr. Dones'...
Cell
Structure
Plants, Animals, Fungi and Protists have
Eukaryotic Cell(s)
Plant Cell Animal Cell
straight edges curved edges
Cell Organization
cell membrane
Eukaryotic cells
have 3 major parts:
1. cell membrane
2. cytoplasm
cytoplasm
3. nucleus
nucleus
cytoplasm is gel-like and
includes all of the
organelles in addition to
many substances
Organelles – membrane-bound
structures in the cytoplasm cytoplasm
Nucleus
Usually largest organelle that is
a round structure near center of
cell containing genetic material
(DNA/chromosomes)
nucleus
The nucleus has many parts.
Nuclear Envelope
two membranes
surround the
nucleus holding
it together
outer membrane
inner membrane
Nuclear Envelope
Nuclear Pores
Nuclear pores help control what
enters and leaves, they allow
________to get out
nuclear pores
Nuclear Pores
RNA
________________ Nucleolus
Dense, circular
region inside of
the nucleus
nucleolus
the nucleolus assembles ribosomes
Nucleolus
Chromatin
the fluid of the
nucleus contains
chromatin
chromatin
Chromatin (relaxed chromosomes)
is made of DNA and proteins
Chromatin
Ribosomes
RNA particles in the cytoplasm in 3-D
structures with proteins that
assemble _________ ________ into
proteins
Blue = proteins
Orange = rRNA
amino acids
Endoplasmic Reticulum
Endoplasmic Reticulum (ER)
ER ER – network of tubes in cytoplasm
where proteins are made
Rough ER –
endoplasmic
reticulum with
ribosomes
attached where
proteins are
made and
transported
through the
tubes of the
ER, eventually
out of the cell
Endoplasmic Reticulum
Ribosomes
not attached
to the ER are
“_______” and
produce
proteins that
stay within
the cell
free
The surface of
smooth ER is
where the cell
makes its
lipids and
detoxifies
drugs (liver).
Endoplasmic Reticulum
ER without any ribosomes is
called smooth ER
Vesicles are transporting sacs both to
and from the Golgi Apparatus. Notice
the vesicles being made at the ends of
the golgi.
Golgi Apparatus
Golgi Apparatus The Golgi apparatus is a stack of membrane
sacs, often shaped like a stack of pancakes,
that receives, processes and packages
proteins
Golgi
apparatus
It makes
vesicles which
are, therefore,
often nearby
vesicles
The Golgi apparatus has 3 functions:
1. To receive ______________ in vesicles from the ER
2. To process (modify) the proteins into a usable
form
3. To package the proteins into _____________ (for use
in or out of the cell)
proteins
vesicles
Lysosomes
Lysosomes
Lysosomes are
vesicles/sacs
containing enzymes
for digesting
unwanted substances.
They act like the
cell’s garbage
disposal. lysosome
Lysosomes clean up cells
Their enzymes digest:
1. worn out cell parts
2. large food particles
3. invading bacteria
enzymes
Vacuoles
Many plant cells
have one large
vacuole
Plant vacuole
Vacuoles are used
to store water,
salts, wastes, or
food, like a
refrigerator
Animal cells have several ________
vacuoles.
small
Some protists, like this paramecium,
use vacuoles to control the amount
of liquid in the cell and for
propulsion.
Mitochondria
Mitochondria
mitochondria
Mitochondria
are bean
shaped
organelles
Mitochondria - the “Powerhouse” of the Cell
Mitochondria release the energy in
food particles (glucose) for use by the
cell as usable chemical energy (______) ATP
Plant Cell Structures
cell wall
vacuole
chloroplast
Chloroplasts The chloroplast
captures energy
from sunlight and
converts it into
chemical energy
(____________)
chloroplasts
they are green
because they
contain the
pigment
chlorophyll
glucose
Internal Structure of a Chloroplast
The chlorophyll in a chloroplast is
where photosynthesis occurs.
Some protists, like euglena, contain
chloroplasts. This is a one-celled
protist is not a plant. However, it does have a
vacuole and chloroplasts
The Cytoskeleton (network of microtubules and
microfilaments)
Function: shape/support
and movement
microtubule
cytoskeleton
Substances Made from Microtubules
Spindle fiber –
forms during cell
division and
separates
chromosomes
Centrioles – near
nucleus –
help
organize
cell division
___________ – many short, hair-
like stuructures on outside of
some cells used for movement
Flagella – long, whip-like structures on
outside of some cells used for
movement
The Cytoskeleton
Cilia
Cell Boundaries
The cell
membrane is
the thin,
flexible barrier
surrounding all
cells that
controls what
enters and
leaves.
cell membrane
Cell Membrane
Cell membranes are complicated
structures made of lipids, proteins and
carbohydrates
Membranes are Lipid Bilayers
one lipid layer
a second lipid layer
phosphate end
phosphate end
fatty acid ends
(they have 2 lipid layers that are flexible
and strong)
Cell membranes usually have water on
both sides of the membrane.
This causes some
phospholipids to point
to the outside of the
cell and some to point
to the inside of the
cell.
extracellular side
cytoplasmic side
Membranes also contain Proteins
protein
Some
proteins form
___________,
while others
form pumps
channels
Present Model of a Cell Membrane
Together, the lipids and proteins make up the
Fluid Mosaic Model for cell membranes.
Fluid Mosaic Model
2 lipid layers
with proteins
The Fluid Mosaic Model fluid means “capable of flowing”
mosaic means “a pattern made from pieces”
a
Cell Wall
the cell wall contains cellulose – very tough and
a major component of _____________ and paper.
it is the plant’s,
algae’s or
fungi’s skeleton
Strong supporting
layer surrounding
cell membrane of
some cells
wood