energy transfer in living things (the mitochondrion and chloroplast) · pdf file ·...

The SUN Project - Energy Transfer in Living Things (1-11)

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Energy Transfer in Living Things

(The Mitochondrion and Chloroplast) Ann Batiza, Ph.D., Mary Gruhl, Ph.D., Tim Herman, Ph.D. and *Dave Nelson, Ph.D.

with contributions by Jean Abreu and lead designer, Mark Hoelzer

Milwaukee School of Engineering and *UW-Madison

Instructional Tools • Plant Cell Mat (6)– highlights an enlarged mitochondrion and

chloroplast

• Animal Cell Mat (1)

• Drawings by Jean Abreu and Mark Hoelzer

Activities 1. Energy Transfer in Living Things – Group Activity

2. Energy Transfer in Living Things – Summary Activity

Key Ideas to Learn Using these Tools 1. Energy from the sun is used to make food through a process called photosynthesis. Only

green plants, algae and some tiny bacteria can carry out photosynthesis. Animals cannot

make their own food. They must eat it. Therefore all life depends upon the sun.

2. Food is made in special organelles within plant and algal cells. That organelle is called a

chloroplast. Food is also made in some photosynthetic bacteria because similar protein

machines that can capture light energy are found on their inner membrane.

3. All living things - plants, algae, fungi, archaea, bacteria (whether or not they are

photosynthetic!) and animals - need ATP to power life. Therefore all living things must make

ATP. ATP is made in the mitochondria of plants, algae, fungi and animals. ATP is also made

with the use of similar proteins on the inner membranes of bacteria.


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The SUN Project - Energy Transfer in Living Things – Group Activity (student version)

Key Idea #1: Energy from the sun is used to make food through a process called

photosynthesis. Only green plants, algae and some tiny bacteria can carry out photosynthesis.

Animals cannot make their own food. They must eat it. Therefore all life depends upon the sun.

All living things need food as a source of energy.

Green plants and some algae and some tiny bacteria can make their own food. They do this through a

process called photosynthesis [to make (synthesis) with light (photo)]. Therefore these green plants,

algae and microbes use light to make their own food.

Animals must eat their food because they cannot make their own. Animals must eat food originally

produced by green plants, algae or microbes.

All living things ultimately depend on light for their energy.

1. Draw a diagram in the box below to explain this true statement. Be sure to include the sun, a plant,

algae or photosynthetic bacterium and an animal, such as a human being.

Name_____________________________________________Teacher_______________Date_____________


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Key Idea #2: Food is made in special organelles within plant and algal cells. That organelle is

called a chloroplast. Food is also made in some photosynthetic bacteria because similar protein

machines that can capture light energy are found on their inner membrane.

All living things are made up of building blocks called cells. Each cell is surrounded by a plasma

membrane, a fatty bag that surrounds it like a balloon. In addition, plant cells have a cell wall around

that membrane to provide a rigid support.

Within cells there are special compartments themselves surrounded by membranes. Each compartment

carries out a special function. Inside plant cells one can find small organelles called chloroplasts. Often

they are green because some of the protein machines in those chloroplasts reflect green light. A

diagram of a plant cell is shown on the right.

2. In the plant cell, can you circle two chloroplasts? Is a

chloroplast smaller or larger than a vacuole?________ Is it

smaller or larger than the nucleus?_____________

Image used with permission from Dave Nelson

We have used some dotted lines to show a blow-up of an actual chloroplast viewed under an electron

microscope.

Study the magnified image of a chloroplast on the left. Notice how it contains several dark membrane-

bound bags that are linked together through tunnels. The dark bags are called thylakoids. A stack of

them is a granum (plural is grana). The stroma is the watery space around the thylakoids. The protein

machines that enable plants and algae to make sugar are located on the thylakoid membranes.

In photosynthetic bacteria, similar protein machines are

located on the inner membrane. Since chloroplasts are about

the same size as bacteria, bacteria don’t contain chloroplasts.

In fact chloroplasts most likely come from a photosynthetic

bacterium!

Look at this light microscope picture of some green plant cells.

Image by SUN teacher, Jean Abreu.

Image from Wikipedia Commons.


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You can see parts of thirty-one plant cells.

Discussion Question #1. About how many chloroplasts can you see within each cell?

Discussion Question #2. Can you see all the chloroplasts in the cell or might there be some that

you can’t see? Why or why not?

The diagram below shows a single plant cell. (It was drawn by SUN teacher Jean Abreu.) The arrow

coming from it indicates an enlarged chloroplast. The arrow coming from the chloroplast shows

proteins within the chloroplast that are important for photosynthesis.

Discussion Question #3. What do the arrows between the figures mean?

Discussion Question #4. Can you imagine how similar proteins might be arranged on the

membrane that surrounds a photosynthetic bacterium?

Image by SUN teacher, Jean Abreu.


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In order to learn more about this process by which protein machines capture light energy, you will use a

large mat that represents a blown-up plant cell. But this is a peculiar plant cell because only the

chloroplast and another organelle called the mitochondrion are highlighted. Study the mat to see which

organelle represents the chloroplast. The thylakoid is represented by the gray circle. What is the brown

area around the gray circle?

4. With your group, place the following labels on the plant cell mat:

Plant cell Plasma Membrane Cell Wall Chloroplast Thylakoid lumen Stroma

Place the sign, “Sugar is made here” in the stroma.

Discussion Question #1. Which kinds of cells can make food (sugar)?

Discussion Question #2. Where does the energy to make sugar come from?

Discussion Question #3. Where should the protein machines that capture light energy be located?

3. Draw a photosynthetic bacterium in

the box. Include the protein machines

that might allow this bacterium to

capture light energy in order to make

sugar.


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Key Idea #3: All living things - plants, algae, fungi, archaea, bacteria (whether or not they are

photosynthetic!) and animals - need ATP to power life. Therefore all living things must make ATP. ATP

is made in the mitochondria of plants, algae, fungi and animals. ATP is also made with the use of similar

proteins on the inner membranes of bacteria.

All living things whether plants, animals, algae, fungi, archaea or bacteria need to convert the energy

stored in sugar into a usable chemical form called ATP. Just like all these other living things, plant cells

need ATP to provide the energy they need to grow, repair themselves and reproduce. They produce

that ATP in their mitochondria (plural of mitochondrion).

The mitochondrion is the small compartment in all cells where ATP is made through a process called

cellular respiration. ATP is used as a source of energy for all life. All living things, whether plant, animal

or microbe, need ATP to power life.

5. Circle three

mitochondria in the

plant cell to the

right.

Below are two images of mitochondria.

Study the 3D diagram of a mitochondrion on the left. Compare it with actual microscopic images of lung

mitochondria on the right produced by Louisa Howard and available through Wikipedia Commons.

The mitochondrion is like a balloon within another balloon. It has an inner membrane (1) and an outer

membrane (2). Because of these two membranes, two spaces are created. The inside space is called

the matrix (4). The space between the membranes is called the intermembrane space (3). We will see

that this space is very important in allowing energy from electrons from sugar to be stored in ATP.

6. Circle two mitochondria in the animal

cell to the left.


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7. On each diagram or image of a mitochondrion, label:

inner membrane outer membrane intermembrane space matrix

(space)

(space)

(membrane)

(space)

(membrane)

Study the series of diagrams below. See how the mitochondrion from a plant cell is made increasing larger

to reveal proteins on its inner membrane.

The protein machines on the membrane allow the mitochondrion to use energy from sugar to make ATP.

8. Draw a bacterium in the box. Where

will protein machines that allow for

production of ATP be located?

Images from Wikipedia Commons.


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On the plant cell mat, the mitochondrion has been made very large.

9. Place the following labels on the plant cell mat:

Mitochondrion Inner membrane Outer membrane Intermembrane space Matrix

Place the sign, “A lot of ATP is made here” inside the gray matrix. This is where ATP is assembled.

10. Discuss the following questions with your group. Refer to the appropriate location on the cell

mat as you discuss them.

Discussion Question #4. Which organelle within this plant cell produces sugar?

Discussion Question #5. Which organelle produces ATP?

Discussion Question #6. Where should the proteins involved in photosynthesis be located?

Discussion Question #7. Where should the proteins involved in cellular respiration be located?

Discussion Question #8. What is the name of the part of the chloroplast in which sugar is made?

Discussion Question #9. What is the name of the part of the mitochondrion where ATP is made?

Discussion Question #10. Why do all living things depend upon light from the sun for life?


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PLANT CELL MAT LABELS

Cut out the following labels and place them in the appropriate place on the Plant Cell Mat.

Chloroplast Activity Labels Plant cell

Plasma membrane

Cell wall

Thylakoid lumen

Stroma

Sugar is made here.

Chloroplast

Mitochondrion Activity Labels Plant cell Plasma membrane

Cell wall

Inner membrane

Outer membrane

Intermembrane space

Matrix

A lot of ATP is made here.

Mitochondrion


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The SUN Project -Energy Transfer in Living Things–Summary Activity (student version)

Ann Batiza, Ph.D., Mary Gruhl, Ph.D., Tim Herman, Ph.D. and *Dave Nelson, Ph.D. with contributions by Jean Abreu and lead designer, Mark Hoelzer

1. Label the plant cell using the following terms:

Cell wall Plasma membrane Chloroplast Mitochondrion

2. Label the chloroplast using the following terms:

Stroma Grana Inner membrane Thylakoid lumen

3. In this electron micrograph of plant cells:

Put a box around one plant cell.

Circle one chloroplast.

Can you see a thylakoid? _____Why or why not?


Image used with permission from Dave Nelson.

Drawings by Mark Hoelzer



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4. What does having chloroplasts mean that plants can do?

5. Label the parts of the mitochondrion on both the diagram and the microscopic image. (Both are

Wikipedia Commons images.)

Inner membrane Outer membrane Matrix Intermembrane space

6. Compare the plant and animal cells.

Do animal cells have chloroplasts? ____ Do plant cells have chloroplasts?_______

Do animal cells have mitochondria?____ Do plant cells have mitochondria?_________

What does this mean that both animals and plants can do?

What does this mean that animals must do with regard to glucose?


Image from Louisa Howard at Wikipedia

Commons.


energy transfer in living things (the mitochondrion and chloroplast) · pdf file ·...

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