Transcript The Cell - Montville.net

Do Now
 What are cells?
 Why do we need them?
 List different types of cells that you
know of…
Objectives
 Describe how cells were discovered
and named.
 Compare and contrast light
microscopes vs. electron microscopes.
 Explain what is found in a basic cell.
Cells
Chapter 7
What are cells?
 Basic structural and functional unit of
all living organisms!
 They come in all shapes and sizes
 Lets take a look…

http://www.cellsalive.com/howbig.htm
Cells!
Egg cell
How did we figure out cells
even existed, what they
looked like, what they do?...
Nerve cell
Bacteria cell
Robert Hooke
 1665- saw dead plant
cells from cork, tree
stems, roots and ferns
using a light
microscope
 Called them “cellulae”
(small rooms) reminded him of the
cubicles or cells where
monks live
Leeuwenhoek
 First person to observe living cells
 Made microscope with a magnification

10X that of Hooke’s- “Father of
microscopes”
Observed spirogyra and protists
The “Cell Theory”
 Scientists expressed 3 main
observations about cells:
All living organisms are composed of
one or more cells
 Cells are the basic units of structure
and organization of all living organisms
 Cells come only from the reproduction
of existing cells

Technology is the key!
 Cells were discovered using MICROSCOPES!
 Compound Light Microscopes

Uses visible light to produce magnified image.
Maximum = 1,000x magnification
 Electron Microscopes


Specimen must be dead 
Use magnets and electrons
Allows much greater magnification
 Ex: Transmission Electron = up to 500,000x
Electron Microscopes
 Transmission Electron
Microscope
Electrons are sent
through a specimen
 Scanning Electron
Microscope
Electrons are sent over
the surface of a
speciment.
Basic Parts of any Cell
 DNA/RNA

Needs some type of genetic information!
 Plasma membrane

Cell’s outer boundary that acts as a barrier
 Cytoplasm


Region of cell that includes fluid, cytoskeleton and all organelles except
the nucleus
Cytosol- part of cytoplasm that included molecules and small particles
but not organelles
 Control Center



Contains a cell’s DNA
Nucleus- membrane- bound structure in eukaryotes
Nucleoid- region of DNA in prokaryotes
Prokaryotic vs. Eukaryotic
 Organisms can be made up of
either prokaryotic or eukaryotic
cells.
Prokaryotic Cells…
 Do not have a
distinct nucleus
 No membranebound organelles
 Ex: bacteria (many
scientists think
that prokaryotes
are similar to the
first EVER
organisms on
Earth)
Eukaryotic Cells…
 Contain a nucleus
 Contain membrane-bound organelles
 Makes up most multicellular organisms
 Ex: US, plants, animals, etc. (also some
unicellular organisms like algae and
yeast)
Lets Review!
 Who discovered cells?
 Why was Leeuwenhoek so special if


someone had already observed cells
before?
What are the different types of
microscopes we talked about. Which
would be best to look at tiny
projections on the surface of a bug?
How are eukaryotes different from
prokaryotes?
Do Now
 Students log in at m.socrative.com or by
launching their app.
Do Not register for accounts.
 Simply enter my unique classroom number
to answer questions

 420161 = My Room #
Objectives
 List the different organelles of a cell.
 Explain the function of each organelle.
 Identify each organelle in a diagram of
a cell.
Organelle Jigsaw Activity
Do Now
 What are the differences between
prokaryotic and eukaryotic cells?
 Why do we need so many more
organelles than bacteria? Explain.
Objectives
 To list and explain the different
organelles found in all eukaryotic cells.
 To compare and contrast animal vs.
plant cells.
 To understand which information
should be studied for the quiz.
Plasma Membrane
 The wall!- protects
the internal
structures of the
cell.
 Determines what
comes in and out of
the cell.
Cytoplasm/Cytoskeleton
 Cytoplasm- clear
fluid that contains
the organelles
 CytoskeletonProvides the
framework for
the cell, holds
organelles in place.
Nucleus
 Nucleus- controls
the cell.
 Nucleolusproduces
ribosomes.
 Nuclear Poresallow things in and
out of nucleus.
Ribosomes
 Makes polypeptide
chains of amino
acids, producing
Proteins.
Endoplasmic Reticulum
 Rough- contains
ribosomes and
synthesizes
proteins.
 Smooth- No
ribosomes,
synthesizes lipids
(fats).
Golgi Apparatus
 Modifies proteins
and fats and gets
them ready for
export!
Vacuoles
 Large water
“bubble” in a plant
cell.
 Maintains the
shape of the cell,
without it, the plant
cell would shrink
and the plant
would wilt.
Lysosomes
 Contain enzymes,
break down
cellular waste
product and
debris.
Centrioles
 Involved in cell
division ( we will talk
about this more later
when we do
mitosis!)
Mitochondria
 Convert oxygen into
energy (we will talk
about this more
when we do cellular
respiration!)
Cilia and Flagella
 Used in cells for
movement
 Used in stationary
cells for moving
substances around
the outside of the
cell.
Chloroplasts
 Capture light
energy and convert
it to chemical
energy (sugar).
Cell Wall
 Rigid structure
 Provides strength
for the cell.
 Works with
vacuole to
maintain “turgor
pressure”
Lets brainstorm…get with a
partner!
 What are the differences between

plants and animals?
http://www.youtube.com/watch?v=zafJKbMPA8
Compare and contrast plant
and animal cells.
Plants
Animals
Quiz Study Guide
 Organelles- what each of them do
 Diagrams- label both plant and animal



cell.
Scientists- who were they and what did
they do?
Cell Theory- what is it?
Prokaryotes vs. Eukaryotes- what’s the
difference?
(the dots)
Start working on your “Journey
through a Cell Project”
There is construction paper, colored
pencils, and markers here for you to
use!
Do Now
 What is the role of the membrane in the
cell?
 How do you think it accomplishes this
role?
 Draw a sketch of what the plasma
membrane looks like.
Objectives
 Understand the role of the plasma
membrane.
 Identify the components of the plasma
membrane and their functions.
 Define diffusion.
What ELSE does the membrane
do?
 Maintains an internal environment that


is different from the external
environment.
Regulates what molecules enter and
exit the cell.
Made of a phospholipid bilayer
“Fluid Mosaic Model” aka the
Plasma Membrane
 Lipids make it fluid
 Proteins and other components are
embedded like a mosaic.
 http://www.youtube.com/watch?v=Qqsf
_UJcfBc
Phospholipid??
 Gylcerol, 2 fatty acid chains, and a


phosphate group
“Phospho”-Hydrophillic (water
loving) Polar (heads)
“lipid”-Hydrophobic (water hating)
Non-polar (tails)
Monolayer
 Fatty Acids
 Cholesterol
 How blood can transport
Fats in bulk!
Water
Bilayer
Water or other hydrophilic substances
Fats (hydrophobic)
Water or other hydrophilic substances
Selective Permeability
 controls the movement of substances
into and out of the cell
 Controls AMOUNT of substances
entering and leaving the cell
The bilayer makes up the plasma
membrane that surrounds the cell!
Which of the 4 organic molecules do you
see in the plasma membrane? –P.C.F.NA.
Cholesterol
 Prevents fatty acid tails from sticking together
Carbohydrates
 Identify chemical signals
Proteins
 Provide channels for transport
Conclusion activity
Do Now- Label the different parts
 What is the name of the entire
structure?
Objectives
 Define diffusion.
 Identify the conditions that effect the


rate of diffusion.
Explain facilitated diffusion.
Compare and contrast active and
passive transport.
How do things get in and out?
 Everybody stand up!
 Gather in a group by the windows,
nobody is allowed behind the lab
tables.
Cell Membrane (transport)
(Ions, Sugars, AA’s,
nucleotides)
(H2O, O2, CO2)
T.P
Large and/or ChargedTransport Protein
Small and/or nonpolar molecules
Diffusion RULE
 DiffusionMovement of molecules from High
concentration to Low Concentration by
random motion

Me
Diffusion RULE
 Dynamic Equilibrium-continues movement
but no NET overall change
Me
Explain what’s happening…
 Perfume-
 Food Coloring-
Initial Conditions
Diffusion
Low
High
High
Low
Diffusion Animations
 http://highered.mcgrawhill.com/sites/0072495855/student_view
0/chapter2/animation__how_diffusion_
works.html
Things that Affect the speed of
Passive Transport
 1. Heat- Hotter the faster
 2. Size- The bigger the slower
 3. State of Matter
Solid- Slow
 Liquid – Fast
 Gas- Fastest

Passive Transport
 Movement of particles across the cell
membrane without using energy
Diffusion of Water
Diffusion of Water- OSMOSIS
 Water can move right through the
phospholipids from high to low
concentration
Facilitated Diffusion
 Movement of materials across the
plasma membrane using proteins
Channel Proteins
Carrier Proteins
Transport Proteins`
 Channel Proteins
Pores that allow charged ions to pass
through the membrane
 Carrier Proteins
Change shape to help molecules pass
through the membrane
Chapter 7
Cellular Structure and Function
Transport Proteins Animation
 http://www.stolaf.edu/people/giannini/fl
ashanimat/transport/channel.swf
 http://www.stolaf.edu/people/giannini/fl
ashanimat/transport/caryprot.swf
Do Now
 What does “passive” transport mean?
 What are the different types of passive

transport?
What is the difference between passive
and active transport?
Objectives
 To explain active transport.
 To understand what happens during

osmosis.
To compare and contrast hypertonic,
hypotonic, and isotonic solutions.
Concept Map of Diffusion
Active Transport
 Specific protein can pump molecules across


the membrane
Usually in opposite direction of diffusion
(Low concentration to high concentration)
Requires ENERGY (ATP)
 http://www.stolaf.edu/people/giannini/flasha
nimat/transport/secondary%20active%20tran
sport.swf
Sodium Potassium Pump
 http://highered.mcgrawhill.com/sites/0072495855/student_view0/c
hapter2/animation__how_the_sodium_pota
ssium_pump_works.html
 http://www.sinauer.com/cooper/4e/animati
ons1302.html
Sodium Potassium Pump
 Type of Active Transport
 Moves three Na+ ions out of the cell
and two K+ ions into the cell
Osmosis
 RULE
-Water always flows via osmosis from
HIGH water concentration to LOW water
concentration through a semi permeable
membrane.
Osmosis
 Which container has more water in it?
http://www.stolaf.edu/people/giannini/flashanimat/transport/osmosis.swf
Osmosis- diffusion of water
across a membrane
 RULE
-Water always flows via osmosis from
HIGH water concentration to LOW water
concentration
-Remember SALT SUCKS- cell shrinks
22% Salt
5% Salt
H2O
H2 O
Osmosis- diffusion of water
across a membrane

RULE
-Water
always flows via osmosis from HIGH
water concentration to LOW water concentration
-Cell bursts!
22% Salt
45% Salt
H2O
H2 O
Chapter 7
Cellular Structure and Function
Cellular Structure and Function
Isotonic Solution
 Water and dissolved substances diffuse
into and out of the cell at the same rate.
Plant Cell
Blood Cell
11,397x
Hypotonic Solution
 Solute concentration is higher inside the cell.
 Water diffuses into the cell.
Plant Cell
Blood Cell
13,000x
Hypertonic Solution
 Solute concentration is higher outside the cell.
 Water diffuses out of the cell.
Plant Cell
Blood Cell
13,000x
3 Types of Solutions
Cell in ________
Solution
Cell in ________
Solution
H2 O
H2 O
H2 O
H2 O
Cell in ________
Solution
H2 O
H2 O
For each solution, determine if the solute concentration of the
solution is high, the same, or low as compared the cell.
3 Types of Solutions
 Plasmolysis: State where plant cells
shrink in hypertonic environment
(animal cells= “crenates”)
 Turgid: State where plant cells swell in
hypotonic solution (animal cells=Lyse)
 Flaccid: State where a plant cell is placed
in isotonic solution
 Cytolysis: State where cells Burst in
hypotonic environment
http://www.tvdsb.on.ca/westmin/science/sbi3a1/Cells/Os
Osmotic Pressure
 Pressure builds up as water moves in
and out via Osmosis
 In plants called Turger Pressure
 Worksheet
Transport of Large
Molecules
 Usually
Transported by
Vesicles
 EndocytosisInto the cell
ExocytosisExiting the cell
What kind of molecules do you think are usually
found in the Vesicle?