Cell Structure and Function
Animal Cell
http://www.phschool.com/science/biology_place/biocoach/cells/identify3.html
Plant Cell
http://www.sciencegeek.net/Biology/review/Sem1Review.htm
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Cell
Cell Theory
Plasma Membrane
Cytoplasm
Cytosol
Nucleus
Prokaryote
Eukaryote
Organelle
Tissue
Organ
Organ System
A. Group of tissues working together
B. Cell with no nucleus
C. Group of cells working together
D. Control center of a cell
E. Cell with a nucleus
F. Smallest unit of life
G. Group of organs working together
H. Everything inside a cell except the
nucleus
I. The fluid part of the cytoplasm
J. Surrounds a cell
K. Our current understanding of cells
L. Small cell part with a special job to do
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Cell
Cell Theory
Plasma Membrane
Cytoplasm
Cytosol
Nucleus
Prokaryote
Eukaryote
Organelle
Tissue
Organ
Organ System
F
K
J
H
I
D
B
E
L
C
A
G
 Cell
—smallest unit of life
 All living things are made of one or many cells
http://www.bewellbuzz.com/general/the-truth-about-cancer-cells/
http://www.ringophone.com/results.asp?searchfield=animals&index=0&type=color
 Robert
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Hooke
1665 English scientist
First person to see cells
Studied thin slices of cork
Called them cells
Never realized that cells were living things
http://www.edu365.cat/aulanet/comsoc/persones_tecniques/Robert_Hooke.htm
http://askabiologist.asu.edu/content/robert-hooke
 Anton
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van Leeuwenhoek
First person to observe living cells in 1673
Called these living cells, “animalcules”
Known as the “Father of Microbiology”
http://www.vanleeuwenhoek.com/His-Microscopic-World.htm
http://www.ucmp.berkeley.edu/history/leeuwen/leeuwmicro.gif
http://www.ucmp.berkeley.edu/history/leeuwenhoek.html
 Matthias
Schleiden (1838)—
German botanist: stated all
plants are made of cells.
http://www.merke.ch/biografien/biologen/schleiden.php
 Theodor
Schwann (1839)—
German zoologist: stated that
all animals are made of cells
http://www.nndb.com/people/357/000096069/
 Rudolf
Virchow (1855)—
German physician: stated
that cells come only from
other cells.
http://clendening.kumc.edu/dc/rv/
 The
work of these men led to the
development of the cell theory.
 Three parts:
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All living organisms are composed of one or more
cells.
Cells are the basic units of structure and function
in an organism.
Cells come only from the reproduction of existing
cells.
 Cells
vary in shape and size according to
their functions.
 Examples:
Nerve cells are long with
extensions for carrying impulses.
http://www.emc.maricopa.edu/faculty/farabee/biobk/08705a.jpg
Red blood cells are microscopic
and round for carrying oxygen.
http://www.sciencequiz.net/jcscience/jcbiology/circulatorysystem/red_blood_cells.jpg
 Most
cells are microscopic.
 Size is limited by the surface area-to-volume
ratio
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Small cells can exchange substances faster than
large cells because small objects have a higher
surface area-to-volume ratio.
SA = 6s2
V = s*s*s
http://bioserv.fiu.edu/~walterm/B/cell_components/4.3%20Effect%20of%20cell%20size%20on%20s.JPG
 Prokaryotes
—cells without a nucleus or
membrane-bound organelles
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Include bacteria and archaebacteria
 Eukaryotes
—cells with a nucleus and
membrane-bound organelles
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Include cells from plants, animals, fungi and
protists
http://www.phschool.com/science/biology_place/biocoach/cells/common.html
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Features common to both prokaryotic and eukaryotic cells
include:
 DNA —genetic material located in the nucleus of eukaryotic
cells and in the nucleoid region of prokaryotic cells
 Plasma Membrane —outer boundary of cell
 Cytoplasm —all the material inside the plasma membrane,
(not including the nucleoid region or nucleus). It includes a
fluid part called the cytosol and many organelles and other
particules floating in it.
 Ribosomes —site of protein synthesis
http://www.phschool.com/science/biology_place/biocoach/cells/common.html
 Unicellular
—organism exists as a single cell
living independently of other cells
 Colonies —groups of identical cells that live
together in a connected group. Cellular
activities are not coordinated.
 Multicellular —specialized cells live together and
become unable to survive independently.
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Organized as follows:
Cells
Tissues
Organ
Organ System
Organism
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Phospholipid bilayer
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Chromosome
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Nuclear envelope
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Nucleolus
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Ribosome
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Mitochondrion
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Endoplasmic reticulum
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Golgi apparatus
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Lysosome
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Cytoskeleton
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Microtubule
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Microfilament
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Cilium
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Flagellum
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Centriole
A. Powerhouse of the cell
B. Site of protein synthesis
C. Contains digestive enzymes
D. Surrounds the nucleus
E. Transports proteins and lipids
F. Structures made of DNA and proteins
G. Surrounds the outside of a cell
H. Plays a role in mitosis
I. Tail-like structures/ help cells to move
J. Hair-like structures/help cells to move
K. Inside the nucleus/ make RNA
L. Help to shape and support a cell
M. Larger structures of the cytoskeleton
N. Smaller structures of the cytoskeleton
O. Package proteins and lipids
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Phospholipid bilayer
G
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Chromosome
F
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Nuclear envelope
D
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Nucleolus
K
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Ribosome
B
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Mitochondrion
A
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Endoplasmic reticulum
E
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Golgi apparatus
O
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Lysosome
C
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Cytoskeleton
L
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Microtubule
M
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Microfilament
N
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Cilium
J
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Flagellum
I
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Centriole
H
 Plasma
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membrane
Surrounds the cell: Controls what gets in and out
Allows cell to interact with its environment
Made of a double layer called the phospholipid bilayer
Described as a fluid mosaic —acts more like a liquid
than a solid because proteins and lipids can move side
to side.
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Phospholipids have a
polar, hydrophilic head
and two nonpolar,
hydrophobic tails made of
fatty acids
Sterols, like cholesterol,
can be found between the
fatty acid tails to provide
firmness and prevent
freezing
http://www.hcc.bcu.ac.uk/physiology/phospholipid02.gif
Note:
Hydrophilic = water loving
Hydrophobic = water fearing
http://annadennis.wikispaces.com/file/view/phospholipid_bilayer.gif/91874047/phospholipid_bilayer.gif
Several types of integral proteins are embedded in the plasma membrane:
Transport Proteins —moves substances across the membrane
Receptor Proteins —recognize and bind to substances outside the cell
Recognition Proteins —glycoproteins with carbohydrate chains that
act as cell-surface markers and identify the cell type
http://golfcourse.mnmsa.org/my_files/hole1and12.jpg
 Cytoplasm
—all the material inside the
plasma membrane (except the nucleus)
 Includes:
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Cytosol—fluid part in which the ribosomes and
molecules float (20% protein)
Cytoskeleton —series of microtubules and
microfilaments that crisscross each other. They
give shape and form to the cell and help
organelles to move within the cell.
(Centrioles: special microtubules that appear
during cell division)
Organelles (except the nucleus)—tiny structures
in the cell: each has its own job to do.
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Control center of the cell
Filled with a jellylike
substance called nucleoplasm
Contains DNA in the form of
chromatin or chromosomes
Surrounded by a nuclear
envelope made of two
phospholipid bilayers.
Envelope has many pores
which act as passageways for
RNA messages
Contain a dense area called
the nucleolus which helps to
make RNA
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Powerhouse of the cell
Site of cellular respiration in
which energy is transferred
from organic molecules
(glucose) to ATP
Active cells like muscle cells
have 1000 or more
mitochondria
Surrounded by a double
phospholipid membrane
Inner folds called cristae is
where the energy reactions
take place.
http://microbewiki.kenyon.edu/index.php/Mitochondria
http://www.darkgovernment.com/news/military-researches-anti-aging/
 Mitochondrial
DNA —DNA found inside the
mitochondria. It allows mitochondria to
reproduce by dividing
 Scientists believe mitochondria originated
from prokaryotic cells that invaded
eukaryotic cells and formed a symbiotic
relationship
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Prokaryotic cells gained protection
Eukaryotic cells got more ATP for energy
 Protein
factories of the cell
 Do not have a membrane
 Consist of two subunits made of protein and
RNA
 Some float free in cytosol
 Others are attached to the ER
http://www.biology4kids.com/files/cell_ribos.html
 Transportation
system of the cell
 Long, folded tubes
called cisternae allow
molecules to move
throughout the cell.
 Two types:
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Rough ER —has
ribosomes attached
Smooth ER —no
ribosomes are attached
Each has a different
function
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Packaging center of the cell
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Consists of stacks of membranes that receive proteins and lipids
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Each layer modifies and packages the proteins and lipids so they can
be sent elsewhere
http://creationrevolution.com/wpcontent/uploads/2010/11/Golgi-Apparatusand-ER.jpg
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Transport vehicles—”Cellular submarines”
Tiny sacs that transport various contents
Classified according to their contents
http://www.biology4kids.com/files/art/cell_lysosome2.gif
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Lysosomes—made by the golgi: they contain digestive
enzymes: these enzymes break down:
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Peroxisomes—not made by the golgi: found in liver and
kidney cells:
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Dead cells (autolysis)
Worn-out cell parts (autophagy)
Large molecules
Glycogen in the liver to release glucose into the blood
Bacteria (lysosomes in WBC)
Detoxify alcohol and drugs
Break down fatty acid
Produce hydrogen peroxide (H2O2)
Glyoxysomes—found in seeds: break down stored food
Endosomes—food vacuoles created after endocytosis
The diagram below summarizes some of the functions of vesicles
http://www.bothbrainsandbeauty.com/wp-content/uploads/2009/12/endomembranesystem.png
http://www.cbu.edu/~seisen/EukaryoticCellStructure.htm
 Plant
cells have all of the same structures as
animal cells plus a few more:
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Cell Wall —rigid layer outside the plasma membrane:
made of cellulose
Central Vacuole —large sac that stores water,
enzymes, wastes and other materials: provides support
for plants when full
Plastids—organelles that contain their own DNA: three
types:
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Chloroplasts—contain chlorophyll: site of photosynthesis
Chromoplasts—contain colorful pigments (carrots, flowers,
etc)
Amyloplasts—store starch (type of Leucoplast: store food)
http://www.harlem-school.com/5TH/sci_pdf/graphics/plant_cell.gif
http://gmgmesjwk.pbworks.com/f/ksjakja.bmp
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