CELL: Structure & Function
Objectives:
– Explain why a cell is like a tiny factory.
– List, label, and describe the functions of the
parts of a typical eukaryotic animal cell.
– Explain how a cell conducts all the processes
of living things, just on a smaller scale.
A Factory Tour
• First, your factory needs a building.
What kind of building
should you have?
Will all factory buildings
be the same?
What features should
your building have?
-Windows?
-Doors?
-Loading dock?
-Security?
Copyright 2002 JTC Corporation
This Building Needs Structure
• Your factory has supports and internal
framework that gives the building shape.
Kam Kiu factory photos
Controlling the Factory
• Next, you need a
control center to
organize what
happens at your
factory.
– Where should the
control center be
located?
– What things might be
inside the control
center?
Asia Pulp & Paper Co. Ltd. Control Room Copyright
2004 SPG Media Limited a subsidiary of SPG Media
Group PLC
What Are You Going to
Make?
• Your factory makes a
product. In order to
know how to make
this product a set of
blueprints are used.
– Why do you need to
use blueprints?
– What kind of
information can be
found in blueprints?
Blueprint rolls
©Copyright 1996 City of
Simi Valley. ISS Hidalgo
blueprints Copyright
©1977-2004 Far Future
Enterprises.
You Need POWER!
• Every factory needs a
power plant that
generates the energy
needed to run the
machinery.
– Where might a factory
get power?
– Why is it helpful for
each factory to have
its own power plant
nearby?
What Are You Working With?
• Every product is made from raw materials.
Manufacturing Your
Product
• Workers operate
machines that
assemble your
product.
© Elkhorn Everbrite Corporation
– Why would a factory
need many machines
and workers?
– Does each machine
make the entire
product or just a small
part?
Putting the Pieces
Together
National Automobile Dealers
Association
• Factories have
assembly lines
where machines or
workers put
together the parts
of a product.
• Some assembly
lines transport
products. Some
package products.
© Elkhorn Everbrite Corporation
Getting The Product Right
• Before they can be
shipped, products
must be sorted
modified, packaged,
and distributed
properly.
– Why are these jobs
important to our
factory?
– What might happen if
these jobs were done
incorrectly?
packaging machine - © 1999-2004 Packexpo.com All rights reserved.
Boxes © Chriscott Supply Co. Warehouse © WSL Corporation
Packing
• Products must be packed in a box or
container before they are shipped.
Shipping
• Products must be shipped from your
factory to their destination.


Where might your
products be shipped?
How might your products
be shipped?
Waste Disposal
• Excess materials or
damaged products
must be discarded
into the waste
disposal.
© Tom Mathews
– What would happen if
waste materials were
allowed to build up and
sit around the factory?
What You Need To Run A Factory
HW: 8 X 11 paper, floor plan
•
•
•
•
•
•
•
•
•
•
•
•
building
supports/ internal framework
control center
blueprints
power plant
raw materials
machines/ workers
assembly line
packing centers
packing/ boxes
trucks/ shipping vehicles
waste disposal
Cell:
A cell is the smallest unit that
is capable of performing life
functions.
Examples of Cells
Amoeba Proteus
Plant Stem
Bacteria
Red Blood Cell
Nerve Cell
Prokaryotic
• Do not have
structures surrounded
by membranes
• Few internal
structures
• 1-celled organisms,
Bacteria
http://library.thinkquest.org/C004535/prokaryotic_cells.html
Eukaryotic
• Contain organelles surrounded by membranes
• Most living organisms
Plant
http://library.thinkquest.org/C004535/eukaryotic_cells.html
Animal
PROKARYOTES
EUKARYOTES
•do not contain nuclei
•contain nuclei
•genetic material that is not
contained in a nucleus
•genetic material is separate
•do not have membranebound organelles
•generally smaller and
simpler than eukaryotic cells
•Bacteria are prokaryotes
• larger and more complex
than prokaryotic cells
•eukaryotic cells are highly
specialized
•Plants, animals, fungi, and
protists are eukaryotes
“Typical” Animal Cell
http://web.jjay.cuny.edu/~acarpi/NSC/images/cell.gif
“Typical” Plant Cell
http://waynesword.palomar.edu/images/plant3.gif
Monday-Quiz: Label an Animal Cell
Organelles
cell parts
HOMEWORKMonday HW
• Obtain a sheet of cell parts and organelles.
• Decide which cell part performs a similar task as
each part of your factory.
• When you have made your decisions, cut out the
cell parts and attach them to your floor plan over
the factory part that performs a similar task.
• When you have finished you will have created a
model of a typical eukaryotic animal cell.
Drill: Fill in the blank with the structure that
matches the description
1. Stores & copies the instructions for making
proteins
2. Makes and finishes proteins that will be
shipped out of the cell
3. Makes proteins that will stay in the cell
4. The “powerhouse” of the cell
5. The “shipping carton” that contains the
finished protein ready to be sent out of the
cell
Cell/Plasma Membrane
“Building”
• Outer membrane of
cell that controls
nutrient and waster
material movement in
and out of the cell
• Double layer of lipid &
protein separating cell
from its environments
• All cells have one
http://library.thinkquest.org/12413/structures.html
Cell Wall
• Most commonly found
in plant cells &
bacteria
• Supports & protects
cells
http://library.thinkquest.org/12413/structures.html
Nucleus
“control center”
© Glencoe Biology 2007
• Controls the cell’s actions
• Contains the cell’s genetic material (DNA).
• Surrounded by a double membrane called the nuclear
envelope/membrane
• Has a dense region called the nucleolus where
ribosomes are formed.
Nuclear Membrane
• Surrounds nucleus
• Bilayer
• Nuclear Pores allow
material to enter and
leave nucleus
Nucleolus
Inside nucleus
Contains RNA to build proteins
http://library.thinkquest.org/12413/structures.html
Chromatin
“blueprints”
• Located in the nucleus
• Composed of nucleic acids
(DNA)
• Condenses into
chromosomes during cell
division
• Contain instructions for
traits & characteristics
Chromosomes during early cell
division – 10,000x
Cytoskeleton
“supports & internal framework”
• A network of protein fibers (microfilaments) and
tubes (microtubules) extending throughout the cell.
–
–
–
–
Provides a framework for the cell.
Helps transport materials.
Anchors the organelles.
Functions in cell movement
© Glencoe Biology 2007
Cytoplasm
contains the “raw materials”
• semi-fluid material inside the plasma membrane
composed of water and organic compounds.
• site of all cellular chemical processes in
prokaryotes
Endoplasmic Reticulum
“assembly line”
• Membrane system of folded sacs and interconnected
channels that produces & moves materials for the
cell.
© Glencoe Biology 2007
-Rough ER – has ribosomes attached; makes protein
-Smooth ER – no ribosomes; makes lipids and
removes waste
Ribosomes- “machines/ workers”
•
•
•
•
Organelles that manufacture proteins
Composed of RNA and protein
Not bound by a membrane.
Some float free in the cytoplasm while others
are attached to the endoplasmic reticulum.
Electron Micrograph of
ribosomes. The ribosomes
operate in chains when
translating a mRNA.
Copyright © Daniel Kunkel
http://library.thinkquest.org/12413/structures.html
Mitochondria
“power plant”
• Changes stored energy into useful energy for
the cell through chemical reactions
• Recycles and decomposes proteins, fats, and
carbohydrates
Golgi Apparatus
“packing plant”
© Glencoe Biology 2007
• A series of flat, membrane-bound sacs that
sorts, modifies, packages, and distributes
molecules
into sacs called vesicles.
http://library.thinkquest.org/12413/structures.html
Vesicles & Vacuoles
“packing boxes”
• Membrane-bound sacs for storage, digestion,
and waste removal
• Contains water solution
• Help plants maintain shape
http://library.thinkquest.org/12413/structures.html
Lysosomes
“waste disposal”
© Glencoe Biology 2007
• Special vesicles that contain powerful
digestive enzymes that can break down large
molecules and old organelles.
• Cell breaks down if lysosome explodes
http://library.thinkquest.org/12413/structures.html
Chloroplast
• Usually found in plant
cells
• Contains green
chlorophyll
• Where
photosynthesis takes
place
http://library.thinkquest.org/12413/structures.html
The Discovery of the Cell
-1665: Robert Hooke used an early compound microscope to
look at a thin slice of cork, a plant material.
-Cork looked like thousands of tiny, empty chambers…“cells”
Idea: The cell is the basic unit of life basic
The Discovery of the Cell
• Anton van Leeuwenhoek: used a single-lens
microscope to observe pond water and other
things.
• The microscope revealed a world of tiny
living organisms.
The Discovery of the Cell
• The Cell Theory
• In 1838, Matthias Schleiden concluded that all plants
were made of cells.
• In 1839, Theodor Schwann stated that all animals
were made of cells.
• In 1855, Rudolph Virchow concluded that new cells
were created only from division of existing cells.
• These discoveries led to the cell theory.
Cell Theory
All living things are made up of cells
Cells are the smallest working units of
all living things
All cells come from preexisting cells
through cell division
Selective Permeability
• A membrane allows some substances to
pass through while keeping others out.
© Glencoe Biology 2007
Structure of the Plasma Membrane
• Composed of a phospholipid bilayer
Arrangement of phospholipid bilayer:
hydrophilic (polar) heads on the outside
hydrophobic (nonpolar) tails on the inside.
© Glencoe Biology 2007
Components of the Plasma Membrane
• Proteins imbedded in membrane.
 Transmit signals to the inside of the cell.
 Anchor the membrane to the internal support structure.
 Transport proteins for tunnels for substances to enter and leave
the cell.
Cholesterol prevents fatty acid
tails from sticking together.
Carbohydrates attach to the
proteins.
 Define the cell’s characteristics.
 Identify chemical signals.
Drill
– The cell membrane is composed of a
phospholipid __________.
– A phospholipid molecule has a _______
head and a _____________ tail.
– What are the three parts of the cell
theory?
– ________ was the first person to use
the word “cell” to describe the tiny boxes
he saw in cork.
Lipids are hydrophobic………….
…but we see water passing through?
1)Theorize that pass through
and repel the fatty acid tails
2)AQUAPORINS
- membrane-spanning proteins
Diffusion
The movement of molecules from a area in
which they are highly concentrated to a
area in which they are less concentrated.
Draw a diagram of an example of
diffusion we saw in class.
See an animation of diffusion
here:
http://lewis.eeb.uconn.edu/lewisho
me/applets/Diffusion/diffusion.html
Osmosis
The diffusion of water across a selectively
permeable membrane.
http://www.usd.edu/~bgoodman/Osmos.htm
If….Water moves from a high concentration of
water (less salt or sugar dissolved in it) to a
low concentration of water (more salt or
sugar dissolved in it), meaning water travels
from a dilute solution (less dissolved in it) to
a concentrated solution (more dissolved in
it)-then……….
http://www.usd.edu/~bgoodman/Osmos.htm
See an animation of osmosis
here:
http://lewis.eeb.uconn.edu/lewisho
me/applets/Osmosis/osmosis.html
Why are osmosis & diffusion
important?
• Homeostasis
• These include exchanging gases (usually CO2 and
O2), taking in water, minerals, and food, and
eliminating wastes.
• These tasks happen at the cellular level-diffusion
-Channel
proteins
-Diff. in concentration + # of specific carrier proteins
= rate
-No energy requirement
ACTIVE TRANSPORT
-transport proteins acting as pumps for small molecules
-endocytosis
-phagocytosis
-pinocytosis
-exocytosis