Name: ______________________________________ Per: ______ Date: ___________
UNIT GOALS-By the end of this unit you will be able to:
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Identify the structures and explain the processes of a cell membrane
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Compare and contrast different types of solutions: hypertonic, isotonic and hypotonic
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Explain the role of osmosis and diffusion in maintaining homeostasis of cells.
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Compare and contrast: active and passive transport
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Explain how cells communicate with one another
Date
12/9
12/11
12/15- Skinny
12/16
12/18
1/5- Skinny
1/6
1/8
Activities
 Lecture: Cell Membrane
 Lab: Model of a Cell Membrane
 Foldable: Types of Proteins
 Reading and Questions
 Lecture: Cell Transport
 T-Chart: Simple and facilitated diffusion
 LAB: Starch and Iodine Diffusion Lab
 Worksheet: Cell Membrane and Diffusion
 Big Quiz: Cell Membrane and Diffusion
 Reading and Questions
 Lecture: Osmosis
 Worksheet: Types of solutions
 LAB: Osmosis in Grapes (start)
 Reading and Questions
 Finish Grapes LAB
 Lecture: Active Transport and Cell Signals
 Worksheet: active transport and cell signals
 20 Questions
 Reading and Questions
 Chapter Review
 Packet Time
 TEST
 Packets Due
 Bill Nye: Mitosis
Vocabulary
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Phospholipid
Lipid bilayer
Cell Surface Marker
Receptor Protein
Enzymes
Transport Proteins
Equilibrium
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Concentration gradient
Diffusion
Carrier Protein
Channel Protein
Simple Diffusion
Facilitated Diffusion
Osmosis
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Active Transport
Pumps
Vesicles
Target Cell
Signal
Binding Specificity
Cell Membrane
 Every cell is surrounded by a _________________________. The cell membrane protects the cell and
helps ______________________________________________ in and out of the cell. By regulating
transport, the membrane helps the cell maintain constancy and order.
Homeostasis
 All living things _______________to their environments
 Homeostasis is the maintenance of stable internal conditions in a _________________
________________________.
 Individual cells, as well as organisms, must maintain homeostasis in order to _______
 One way a cell maintains homeostasis is by controlling the movement of substances across the
______________________________________
Lipid Bilayer
 The cell membrane is made of _________________________
 A phospholipid is a specialized lipid made of a phosphate “_____________” and two fatty acid
“_____________”
 The phosphate head is polar and is ___________________to water
 The fatty acid tails are nonpolar and are___________________ by water.
 Structure: because there is water inside and outside the cell, the phospholipids form a
_____________________ called the ___________________________
 Barrier- Only certain substances can _________________________ the lipid bilayer.
 The phospholipids from a _________________ through which only small, nonpolar substances can pass
 __________ and most __________________________ are repelled by the nonpolar interior of the lipid
bilayer
Membrane Proteins
 Various _________________ can be found in the cell membrane. Some proteins face inside the cell and
some face outside
 Other proteins may _______________________ the lipid bilayer and face both inside and outside
Proteins in Lipids
 Proteins are made of __________________.
 Some amino acids are polar and others are nonpolar
 The amino acids are repelled and attracted to __________________________ of the bilayer
 These opposing attractions help _________________________ in the membrane
Types of Proteins
 ______________________________- like a name tag, a chain of sugars acts as a marker to identify
each type of cell.
 For example- liver cells have a different _______________________ than heart cells.
 Cell surface markers ____________________- the cell type.
 _____________________________- enable a cell to sense its surroundings, recognize and bind to
certain substances outside the cell
 When this happens, it causes _____________________________________
 _________________- Help to ____________________- reactions. They are proteins in the cell
membrane that help with important biochemical reactions inside the cell
 ______________________________- Help substances move across the cell membrane
 Many substances that the cell needs ___________________ through the lipid bilayer. Transport proteins
__________________________________ of these substances into and out of the cell.
Cell Transport
 The cell must ________________ substances of varying size, electrical charge and composition into and
out of the cell. Substances may __________________________ the cell in a variety of ways.
 Sometimes the cell must ________________________ to move a substance across the cell membrane. In
_______________________, the cell is required to use energy to move a substance. In
___________________________, the cell does not use energy.
Diffusion
 In solution, randomly moving molecules tend to ____________________________. When the space is
filled evenly, a state called _______________________ is reached.
 The amount of a particular substance in a given volume is called the _______________ of the substance.
When one area has a higher concentration than another area does, a concentration
_____________________exists.
 Substances move from an area of _________________ concentration to an area of
_______________concentration. This movement down the concentration gradient is called
______________________.
 Diffusion: the ____________________________________ from higher density to lower density
Passive Transport
 The cell membrane separates the ___________________ from the ___________ ________________
the cell. Some substances enter and leave the cell by _________________________across the cell
membrane.
 The __________________________________________ depends on the concentration gradient and
does NOT require energy
 In passive transport, substances cross the cell membrane down their concentration gradient. Some
substances diffuse through the ______________________ and others diffuse through
___________________________________
Simple diffusion
 ___________________________________________ can pass directly through the lipid bilayer. This
type of movement is called ________________________. Simple diffusion requires
______________________.
Facilitated diffusion
 Many ions and polar molecules that are important for cell function ________________
_______________________ through the nonpolar lipid bilayer.
 In _____________________________, __________________________ help these substances
diffuse through the cell membrane.
 There are two types of _____________________________________:
 Channel proteins
 Carrier proteins
 Channel Proteins
 Ions, sugars and amino acids can diffuse through these. Channel proteins serve as a
_______________________________________________. Each channel allows the diffusion
of a ______________________________ that has the right side and charge. For example, a
sodium channel, can only transport sodium
Carrier Proteins
 Transport substances that fit within their _____________________. A carrier protein binds to a
specific substance on one side of the cell membrane. This binding causes the
____________________________________. As the protein’s shape changes, the substance is
_____________________ the membrane and is released on the other side
OSMOSIS
 Water can move across a ____________________________ membrane. The movement of water is called
osmosis
 Selectively permeable membrane: A membrane that allows _______________________
________________________________________________________
 Osmosis allows cells to maintain ____________ balance as their environment changes.
 Osmosis in cells strongly depends on the ________________the cells are in.
Types of solution
 ________________________: the fluid outside is MORE concentrated (with solute) than inside.
_______________________ of the cell, causing the cell to __________
 ________________________: The fluid outside is_________________ concentrated (with solute)
than inside. Water __________________ the cell and the cell _________
 _____________: water moves into and out of the cell at the _______________. No net change in water
movement occurs and ______________________is reached. The concentration is the ____________
inside and outside the cell. The cell stays the same.
Active Transport
 Sometimes, cells must transport substances _________________ their concentration gradients. This
movement is called __________________________ because the cell must use energy to move these
substances.
 Active transport _________________________ to move substances against the concentration gradient.
Pumps
 Many active transport processes use _________________________ that need ATP to actively transport
materials in and out of the cell
 One of the most important carrier proteins in animal cells is the
___________________________________.
 The sodium-potassium pump actively transports both Na+ and K+ ions across the cell membrane.
Vesicles
 Many substances such as proteins and polysaccharides are _____________________ to be moved by
transport proteins. Instead, they cross the cell membrane in a _________.
 A vesicle is a piece of the cell membrane that formed a ___________________ ______________.
Cell Communication
 We communicate in many ways to share information.
 To coordinate activities with another person you might use your cell phone, write a note, talk or use
facebook…
 Cells in multicellular organisms depend on each other to survive and must communicate to coordinate
activities within the body.
 Cells use various methods of __________________. These methods vary depending on whether the
target is __________________________________. They also depend on whether the target is
_________________________________.
 Cells communicate and coordinate activity by ____________________________ ___ that carry
information to other cells.
 A signaling cell produces a signal, often a molecule, that is detected by the
_________________________
 The target cells have specific proteins that _________________________________
__________________________
 _________________________- neighboring cells can communicate through direct contact between their
membranes.
 _____________________________ may act locally, a few cells away from the originating cell
 ______________________________ are carried by hormones and nerve cells.
 A _________________________________________________________________ to the few
signals that are important to its own function.
 This response to some signals, but not others, is made possible by ______________
____________________ found in the cell membrane
 ________________________________- A receptor protein binds only to signals that match the
specific shape of tis binding site.
 Once it binds the signal molecule, the _____________________________________ in the membrane.
This change in shape relays information to the cytoplasm of the target cell.
 The cell may respond to a signal by changing its membrane permeability, by activating enzymes or by
forming a second messenger.
 _________________________- transport proteins may open or close in response to a signal
 ___________________________- some receptor proteins activate enzymes in the cell
membrane. Enzymes can trigger a chemical reaction in the cell
 _________________________-When a signal molecule binds outside the cell causing changes in
the cytoplasm and nucleus of the cell.