B3 Active Transport
Mrs S Carpenter
TITLE: Active Transport
Objectives
• What is active transport – grade C
• Describe the process and know where active
transport occurs in plants and animals? Grade
B
• Explain the benefits to the organism of using
active transport. Grade A
Outcomes:
Pupils will:
• Produce their own definition and
amend it to B3 – grade A standard.
• Produce a table with plant and animal
examples of active transport.
• answer exam style questions
KEY WORDS:
Active transport
Diffusion
Concentration
gradient
Starter
Complete the following:
Diffusion is the movement of particles
………… a ………….. gradient from an area of
……………….. concentration to an area of
…………………………..
What is a Concentration Gradient?
• Hills and graphs have gradients
1) Which one has the steepest gradient?
2) Which one moves up a gradient and which moves down a gradient?
moving down a concentration
gradient
Which way will the particles move?
What does the phrase active transport
mean?
• Look for clues in the words above.
Write a definition
Can you think of any places in plants and animals where
this may occur? Produce a table and add/change details as
the lesson continues
Now watch this clip
• Diffusion and Active Transport - My GCSE
Science
• What did you learn? Add details to your
notes.
Do you want to change your definition? Amend as
necessary.
moving UP or against a concentration
gradient
ENERGY
The particles can move up the concentration gradient if
energy is used
This is active transport
Higher
Sometimes it is worth
using up energy when
a resource is
particularly valuable
and its transport is
really important!
Do you remember the name of the
‘energy currency’ that is used?
Add this term to your definition.
AQA Science © Nelson Thornes
Ltd 2006 9
Active transport
• This DOES Require energy
• Particles move against a concentration
gradient.
• The energy is needed to make “pumps” move
particles the wrong way.
• E.g. glucose from the intestine into the blood
Active Transport
Active transport in plants
Active Transport
• Active transport occurs across semi permeable
membranes and moves particles from a low
concentration to a higher concentration. This
is against the concentration gradient.
• Transport or carrier proteins are needed to get
these molecules into the cells and these use
energy.
• Cells that do active transport contain large
numbers of mitochondria.
Why? Important in both plants &
animals
• PLANTS
– Allows the absorption of dilute minerals into the
plant against a concentration gradient
• ANIMALS
– Allows the absorption of glucose (essential for
respiration within nervous tissue) into the blood
from the kidneys and ileum against a
concentration gradient
Rate of active transport
Rate of active transport depends on
the rate of respiration
0
Draw a quick sketch. Describe what
this graph shows you.
Rate of respiration
Active Transport
Inside of cell
Outside of cell
ATP
ADP
P
Na+ high
concentration
Glucose
Lumen of small
Intestine
Co Transport
Na+ low
concentration
Glucose
Epithelial Cell
K+
Active Transport
Facilitated Diffusion
Glucose
K+
Blood Capillary
Why? Important in both plants &
animals
• SEA LIFE
– High concentration of salt in sea water
• To absorb salt: SALT GLANDS
– Located near the eyes
– Remove salt from water against concentration
gradient
– Excrete a salt solution 6x stronger than urine
What affect does cyanide have on the
body? Challenge.
• Statement. Cyanide stops active transport
Cyanide affects mitochondria. What will happen?
Mitochondria are involved in respiration, so no
respiration.
This means the organism dies.
Questions
a) Explain how active transport works in a cell
b) Give some examples of a situations when a
substance cannot be moved into a cell by
osmosis or diffusion, and how active transport
solves the problem
c) The processes of diffusion and osmosis do not
need energy to take place. Why does an
organism have to provide energy for active
transport and where does it come from?
Plenary
• Make a list of similarities and differences
between active transport and diffusion
Reflect and assess your learning
• What grade are you working at for this topic?