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Cell Transport Worksheet
Part 1: Diffusion:
What is it? (IN YOUR OWN WORDS):
What is a concentration gradient?
Does it go with or against a concentration gradient?
Here’s a picture of a concentration of gas molecules in a container. Show that
you understand diffusion by drawing what they’d look like after 5 minutes and after
5 hours. Explain what has happened for each.
Start
5 minutes
5 hours
Here’re 2 drawings of cells. Show what the concentration of molecules would
look like after 5 minutes and 5 hours. Explain what has happened for each. Draw
arrows to show movement of the molecules. The larger the arrow, the more molecules
would move.
Start
5 minutes
5 hours
Start
5 minutes
5 hours
Part 2: Osmosis:
What is it? (IN YOUR OWN WORDS):
How is this different from diffusion?
Here are 3 pictures of cells. Draw arrows to show the direction that water will
move due to osmosis. The larger the arrow, the more water molecules would move.
Explain why this happens. Identify each cell as being in an isotonic, hypertonic or
hypotonic solution.
Part 3: Facilitated Diffusion
What is it? (IN YOUR OWN WORDS):
How is this different from diffusion?
How is this different from osmosis?
Here are two pictures of facilitated diffusion. Below each, write a series of steps that
explain what is happening to move the molecules into the cell. Also number where
these steps take place in the diagram.
Conclusions:
Do any of these three processes use any energy to happen? Explain.
These three are all examples of what kind of transport in the cell?
Which ones go with a concentration gradient? Which ones against it? Explain.
Part 4: Active Transport/Protein Pumps
Why is active transport called “active.” (that is, how is it different from the
examples you’ve looked at so far?
How is it similar to facilitated diffusion?
Does it go with or against a concentration gradient? Explain.
Here is a picture of a protein pump, specifically something called the sodiumpotassium pump. Explain what is going on in each step.
Step 1:
Step 2:
Step 3:
Step 4:
Part 5: Transport in vesicles
If things are moving into the cell, the process is called __________________________.
If the stuff moving in is food, the process is called ____________________________.
If the stuff moving in is water, the process is called ____________________________.
If stuff moves out of the cell, the process is called ___________________________.
Here’s a picture of things entering the cell. Explain what is happening in each step.
Here’s a picture of things leaving the cell. Explain what is happening in each step.
Which of the above processes takes some of the cell membrane and moves it into
the cell?
Which of the above processes adds to the cell membrane?
Conclusions:
If you leave something alone to diffuse, eventually it reaches a balance. What is
the balance called? Does this mean that the molecules are not moving
anymore? Explain.
Does this mean that the molecules are not moving anymore when a cell is in an
isotonic solution? Explain.
Sea water has a larger concentration of salt (and other solutes) than the human
body. Why it is bad to drink sea water? What would happen to your cells?
What specifically would happen to a jellyfish if it was placed in freshwater (think
about osmosis)?
How do plasmolysis and turgor pressure in plant cells relate to the processes of
cell transport (i.e. what process cause them?)
Here’s a plant cell after its environment was changed. The dark gray areas are
empty space between the cell membrane and cell wall and the white area inside
the cell is the central vacuole. What kind of solution was the cell placed in and
what caused this to happen to the cell?
Draw what an animal cell would look like if it was placed in the same kind of
environment.
Sum up the processes:
Picture
Process:
Uses energy ?
(yes/no)
Against
Concentration
gradient?
Answer key__
Name: __
Period: _____ Date: ____________________
Cell Transport Worksheet
Part 1: Diffusion:
What is it? (IN YOUR OWN WORDS):
molecules move from area where there’s lots to where
there’s a little
What is a concentration gradient?
Difference in concentration in two areas (high vs. low)
Does it go with or against a concentration gradient?
With, that is from high to low concentration
Here’s a picture of a concentration of gas molecules in a container. Show that
you understand diffusion by drawing what they’d look like after 5 minutes and after
5 hours. Explain what has happened for each.
Start
5 minutes
Start to spread out
5 hours
spread out evenly
Here’re 2 drawings of cells. Show what the concentration of molecules would
look like after 5 minutes and 5 hours. Explain what has happened for each. Draw
arrows to show movement of the molecules. The larger the arrow, the more molecules
would move.
Start
5 minutes
Start to spread out
5 hours
spread out evenly
Start
5 minutes
Start to spread out
5 hours
spread out evenly
Part 2: Osmosis:
What is it? (IN YOUR OWN WORDS):
diffusion of water across a membrane
How is this different from diffusion?
Only water
Across membrane
Here are 3 pictures of cells. Draw arrows to show the direction that water will
move due to osmosis. The larger the arrow, the more water molecules would move.
Explain why this happens. Identify each cell as being in an isotonic, hypertonic or
hypotonic solution.
Hyper tonic solution
Water moves out to water down
the surroundings
Hypotonic solution
Water moves into the cell to
water it down
Isotonic solution
Water moves in and out
Part 3: Facilitated Diffusion
What is it? (IN YOUR OWN WORDS):
diffusion with help of a protein
How is this different from diffusion?
Protein involved, larger molecules, charged molecules (ions)
How is this different from osmosis?
Not just for water
Here are two pictures of facilitated diffusion. Below each, write a series of steps that
explain what is happening to move the molecules into the cell. Also number where
these steps take place in the diagram.
1
.
1
.
2
.
2
.
3
.
3
.
1. molecule binds to protein (specific)
2. protein changes shape
3. molecule released
Conclusions:
Do any of these three processes use any energy to happen? Explain.
Not cell’s. All just happen by molecules moving
randomly (KE)
These three are all examples of what kind of transport in the cell?
Passive transport
Which ones go with a concentration gradient? Which ones against it? Explain.
All except osmosis. It can go from where water is in
high concentration, depending on the
concentration of other molecules.
Part 4: Active Transport
Why is active transport called “active.” (that is, how is it different from the
examples you’ve looked at so far?)
Uses the cell’s energy (ATP), the cell has to do something
(be active)
How is it similar to facilitated diffusion?
Uses proteins to help things move through the membrane
Does it go with or against a concentration gradient? Explain.
Against. Moves things from low to high concentration.
Here is a picture of active transport, specifically something called the sodiumpotassium pump. Explain what is going on in each step.
Step 1:
three sodium atoms bind with protein
Step 2:
energy is used to change to shape
Step 3:
the sodium atoms are released outside the cell, 2
potassiums bind
Step 4:
the protein changes shape and the potassium atoms are
left inside the cell
Part 5: Transport in vesicles
If things are moving into the cell, the process is called
If the stuff moving in is food, the process is called
phagocytosis.
If the stuff moving in is water, the process is called
If stuff moves out of the cell, the process is called
endocytosis.
pinocytosis.
exocytosis.
Here’s a picture of things entering the cell. Explain what is happening in each step.
1
3
2
1. cell membrane starts to collect molecules…
2. …closes off…
3. … and makes a vesicle
Here’s a picture of things leaving the cell. Explain what is happening in each step.
1
2
3
1. vesicle gets close to cell membrane…
2. …attaches to cell membrane…
3. …opens and releases molecules
Which of the above processes takes some of the cell membrane and moves it into
the cell?
First one (endocytosis)
Which of the above processes adds to the cell membrane?
Second one (exocytosis)
Conclusions:
If you leave something alone to diffuse, eventually it reaches a balance. What is
the balance called? Does this mean that the molecules are not moving
anymore? Explain.
Equilibrium
No. They move back and forth equally, no net movement
Does this mean that the molecules are not moving anymore when a cell is in an
isotonic solution? Explain.
No. They move into and out of the cell equally.
Sea water has a larger concentration of salt (and other solutes) than the human
body. Why it is bad to drink sea water? What would happen to your cells?
Salt would be hypertonic. Your cells would lose water
(dehydrate) by osmosis
What specifically would happen to a jellyfish if it was placed in freshwater (think
about osmosis)?
Freshwater would be hypotonic. Water would enter the
jellyfish by osmosis and it might explode.
How do plasmolysis and turgor pressure in plant cells relate to the processes of
cell transport (i.e. what process cause them?)
Osmosis causes plasmolysis when the cell loses water by
osmosis. This would also cause it to lose turgor
pressure
Here’s a plant cell after its environment was changed. The dark gray areas are
empty space between the cell membrane and cell wall. What kind of solution
was the cell place in and what caused this to happen to the cell?
Hypertonic
Osmosis (water left and the cell shrunk)
Draw what an animal cell would look like if it was placed in the same kind of
environment.
Sum up the processes:
Picture
Process:
Uses cell’s
Energy?
(yes/no)
Against
Concentration
gradient?
Diffusion
no
no
Facilitated
diffusion
no
no
protein
pump
yes
can be
Endocytosis
yes
can be
Exocytosis
yes
can be