Download Membrane and Transport

DO NOW (WRITE Q AND A IN SOURCEBOOK)
1.
2.
3.
What are some things that pass through a
window screen?
What are some things that cannot pass through
a window screen? Why is it important to keep
these things from moving through the screen?
The cell is surrounded by a membrane
which regulates what enters and leaves
the cell. Why is it important to regulate what
moves into and out of a cell?
MEMBRANE AND TRANSPORT
Video Introduction: The Cell Membrane King
https://www.youtube.com/watch?v=6fhbbFd4icY&l
ist=UUb2GCoLSBXjmI_Qj1vk-44g
THE CELL MEMBRANE
selectively permeable:
Let in stuff they need, kick out stuff they
don’t need.
 To get into the cell, materials must pass through
the cell membrane.
 Two reasons this is important:
1. How cells acquire what they need and get
rid of what they don’t
2. How cells communicate with one another

PHOSPHOLIPID BILAYER
Cell membranes are made out of phospholipids.
 There are hydrophilic (water loving) and
hydrophobic (water hating) parts.

TYPES OF TRANSPORT
Two categories of transport: active and passive
 Passive transport doesn’t require any energy.
 Diffusion: transport of stuff (oxygen).
 Particles want to spread out.
 Osmosis: transport of water.
 Osmosis and Diffusion are examples of
PASSIVE transport.
They don’t require any energy.

ACTIVE TRANSPORT
Channel proteins act like hallways.
 Active transport moves things in the opposite
direction of the concentration gradient.

SOLUTIONS: 3 TYPES

Solution: something dissolved in water
(salt, the solute)
 Hypertonic
 Hypotonic
 Isotonic

The kidneys regulate the concentration of blood
plasma.
HYPERTONIC
the solution has a higher solute concentration
than the cell
 water moves out

HYPOTONIC
the solution has a lower solute concentration
than the cell
 water moves in

ISOTONIC
concentration of solute
same inside cell as
outside (balanced)
 water moves in and out
 When things transport
to attempt to become
isotonic it’s called:
moving across the
concentration gradient

Blood
DO NOW: COPY THE PICTURE. LABEL HYPERTONIC,
HYPOTONIC, OR ISOTONIC. DRAW AN ARROW
SHOWING THE DIRECTION THE WATER WILL MOVE.
DO NOW: IN SOURCEBOOKS
The cell membrane is made up of a _____ bilayer.
A) Carbohydrate
B) Lipid
C) Protein
D) None of the Above
 True or False: All cells have a cell membrane.
 The lipids in the bilayer have tails that are _____
meaning that they repel (or do not like) water.
 True or False:
Some molecules can pass through the bilayer
without help.

WRITING TO WIN: FOCUSED FREE WRITE
6-7 sentences
 5-6 key terms


Prompt: I am _______, the lipid bilayer.

Key terms:
Cell membrane
structure
surround
hydrophilic
lipids
movement
semipermiable
properties
bilayer
Double
hydrophobic
proteins
DO NOW:
Mrs. Stoops has a saltwater fish (Nemo) that she
put into a freshwater fish tank.
 What will happen to the fish and why?
 Draw a sketch to illustrate your answer.


Hint:
Hypertonic
Isotonic
Hypotonic
Swell
Shrink
Balanced
VOCABULARY BINGO
Homeostasis
 Phospholipid
 Fluid mosaic
model
 Cell membrane
 Selective
permeability
 Receptors
 Diffusion
 Concentration
gradient

Osmosis
 Hypertonic
 Hypotonic
 Passive transport
 Facilitated
diffusion
 Isotonic
 Active transport
 Phagocytosis
 Endocytosis
 Exocytosis

Hydrophilic
 Hydrophobic
 Kidneys
 Protein channel
 Pinocytosis
 Turgid
