Cell Membranes
10/8 & 10/10/12
SWBAT infer how molecules
move across a cell
membrane without energy.
Agenda:
1) Warm-up
2) Potato Demo
3) Cell Membrane
Diagrams
4) Diffusion Lab
5) Osmosis & Diffusion
Output
HW: Organize notebookdue Weds. Finish Output pg.
72
Warm-up 10/8
1) If you are in a crowded
room, and a door
opened to another
room, where would you
want to go? Why?
2) Which one takes more
energy: a fish swimming
with the current or into
the current? (imagine
swimming towards the
waves or up a river
versus with the waves)
3) Read the Rubric given to
you on your way in.
Potato Demonstration
• One slice has been placed in salty water
• One slice has been placed in distilled water
(contains no extra molecules or minerals)
• On the top of page 72, write down your
predictions of what you think will happen to
each slice of potato after about 15 minutes
Diffusion Lab Vocabulary
•
•
•
•
Permeable- will allow things to pass through
Hypertonic- “hyper”= more of the substance
Hypotonic- “hypo” = less of the substance
Selectively permeable- Some things are
allowed to pass through
Osmosis and Diffusion Output
• On pg. 72 draw a picture of a cell that is in a
hypotonic solution (such as the iodine
solution) and what would happen to the cell if
its membrane is semi-permeable to the
molecules to the solution
• Draw a picture of a cell that is in a hypertonic
solution and what would happen to the cell
(HINT: this should be similar to your drawing
of the beaker and baggie, the baggie is like the
cell).
SWBAT explain the
difference between active
and passive transport in
cells.
Agenda:
1) Warm-up/Review Lab
2) Passive and Active
Transport Notes
3) Molecular Movement
Activity
4) Review Homework
5) Update Glossary
HW: Active Transport
Worksheet- Cells Test Next
Wednesday
Warm-up 10/10
1) What part of the cell
membrane is
hydrophilic?
2) Which part of the cell
membrane is
hydrophobic?
3) What happened during
the diffusion lab last
class?
4) What did the plastic bag
represent?
1) What part of the cell membrane is
hydrophilic?
– The phosphate head
2) Which part of the cell membrane is
hydrophobic?
– The lipid tail
3) What happened during the diffusion lab last
class?
– The plastic bag that contained starch was
permeable to the iodine in the beaker.
4) What did the plastic bag represent?
– A cell membrane
Objective: To compare active and
passive transport.
Title: Active and Passive Transport
Pg. 75; 10/10/12
Different Types of Transport
1) Passive Transport: movement of a substance
across a cell membrane that does NOT
require energy. (goal to get the concentration
the same on both side of membrane)
– Allows water, oxygen, CO2, and small molecules
to pass through
2) Active Transport: movement of a substance
across a cell membrane that DOES require
energy
– Allows larger or charged molecules to pass
through
Passive Transport
• Type 1:
– Diffusion: movement from high concentration to
low concentration (any type of small molecule)
• Type 2:
– Osmosis: refers to the movement of water from
high concentration to low concentration.
• Type 3:
– Facilitated Diffusion: molecules move from an
area of higher concentration to lower
concentration with the help of carrier proteins
Active Transport
• Type 1:
– Ion Pumps: carrier proteins pump ions and
molecules across the membrane; energy required
comes from ATP
• Type 2:
– Bulk movement: large molecules moved across
the cell membrane in membrane-bound sacs
• Exocytosis: wastes and cell products are package by
Golgi apparatus into vesicles, which are secreted OUT
of the cell
• Endocytosis: A portion of the cell membrane surrounds
macromolecules and form a tiny vesicle, which moves
INTO the cell
2 Types of Endocytosis
• Pinocytosis: movement of liquids INTO the cell
• Phagocytosis: movement of solids INTO the
cell
Types of
Transport
Passive
Transport
Diffusion
Osmosis
Active
Transport
Facilitated
Diffusion
Ion Pumps
Bulk
Movement
Endocytosis
Pinocytosis
Exocytosis
Phagocytosis
Vocabulary- Add ALL to Glossary
•
•
•
•
•
•
Passive Transport
Active Transport
Diffusion
Osmosis
Facilitated Diffusion
Ion Pump
•
•
•
•
•
Bulk Movement
Endocytosis
Exocytosis
Pinocytosis
Phagocytosis
Osmosis and Diffusion Output
• On pg. 72 draw a picture of a cell that is in a
hypotonic solution (such as the iodine
solution) and what would happen to the cell if
its membrane is semi-permeable to the
molecules to the solution
• Draw a picture of a cell that is in a hypertonic
solution and what would happen to the cell
(HINT: this should be similar to your drawing
of the beaker and baggie, the baggie is like the
cell).