3217 The Cell- Respiration and Photosynthesis

Photosynthesis takes place in the chloroplasts of green plants only.

Respiration takes place in the mitochondria of all living organisms,

plant or animal.

Upon successful completion of this unit, you should be able to do the following:

1. Explain and describe the similarities and differences between chloroplasts

and mitochondrion.

2. Explain the function of the cellular mitochondrion and chloroplast.

3. Explain and describe cellular respiration in detail.

4. Explain and describe photosynthesis in detail.

5. Write the general equation for respiration.

6. Write the general equation for photosynthesis.

7. Explain how photosynthesis and respiration can be a cycle.

8. Be able to use the following terms in their correct context:

mitochondrion

chloroplast

respiration

photosynthesis

ATP

Oxygen

Carbon dioxide

Water

BIO 2 GO!

The Cell – Respiration and Photosynthesis

3217

The cell is the basic unit of life. Everything that is needed for the living

organism to survive is done in the cells of that organism. Because of this, certain

cell components, or organelles, are specialized to do certain things. For instance,

within the cell are structures known as chloroplasts and mitochondria. Both of

these organelles are highly specialized structures that perform a very useful and

specific task.

The chloroplasts and mitochondria are both needed to capture and utilize

energy for the cells. Chloroplasts are the structures in which photosynthesis

takes place. Mitochondria are the structures in which respiration takes place.

Photosynthesis makes energy (glucose). Respiration breaks down glucose so the

energy in the form of ATP is released for use by the cell. Only plants have

chloroplasts. Both plants and animals have mitochondria.

REMEMBER THIS!!!

Photosynthesis takes place in the chloroplasts. Respiration takes place in

the mitochondria.

Interesting Scientific Fact: Chloroplasts are green because they contain the

green chemical, chlorophyll. Chloroplasts are what give plants their green color.

Question 1. What kinds of cells have chloroplasts and what to they do?

Question 2. What kinds of cells have mitochondria and what do they do?

Question 3. Explain why the sun is the source for all energy on Earth.

Chloroplasts:

Chloroplasts are the site where photosynthesis takes place in green plants.

There are often many chloroplasts in each cell.

Photosynthesis is the process whereby green plants take the energy from the

sun and use it to combine water and carbon dioxide to make glucose and

oxygen. The following is a simple equation for photosynthesis.

In the chloroplasts

Water + carbon dioxide (with the energy of light) glucose + oxygen

Picture of a plant cell with the chloroplasts clearly seen.

REMEMBER THIS!!!

Photosynthesis captures the energy of light and converts it into glucose.

Glucose is a source of energy that is useable by the cell.

Photosynthesis always takes place in the chloroplasts.

Mitochondria:

Mitochondria are the site where respiration takes place in all cells. There are

often many mitochondria in every cell. Muscle cells usually have more

mitochondria than other cells because they need more energy to function properly.

Respiration is the process whereby cells break down glucose into carbon

dioxide and water to release energy, ATP, for use by the cell. This energy

(ATP) is needed to perform all life functions. The following is a simple equation for

respiration.

In the mitochondria

Oxygen + glucose water + carbon dioxide + ATP (energy)

Picture of the mitochondria

REMEMBER THIS!!!

Respiration releases the stored energy in glucose for use by the rest of the

cell. Respiration always takes place in the mitochondria. All cells have

mitochondria.

Question 4. What is the purpose of photosynthesis?

Question 5. What is the purpose of cellular respiration?

Question 6. Explain how photosynthesis and respiration are a cycle.

Summary

The Cell – Respiration, Photosynthesis

3217

All cells need energy to survive. With no energy, all living things die.

Chloroplasts and mitochondria are the cellular organelles responsible for creating

energy in the form of ATP that is useful to all cells.

In photosynthesis, the energy in light is used to combine carbon dioxide and

water to make glucose in the chloroplasts of all green plants. In this process

oxygen is a waste product and is released to the atmosphere.

In respiration, oxygen is combined with glucose to make ATP. ATP is an

energy source that is readily usable by the cells. ATP is made in the

mitochondria. Carbon dioxide and water are waste products of respiration and are

released into the environment. Cellular respiration occurs in both plant and

animal cells.

It is interesting that photosynthesis and respiration are a cycle. The waste

products of one reaction are needed to begin the other reaction.

Photosynthesis and respiration need each other in order to have the necessary

materials to start their reaction. That is why it is important that plants and

animals maintain a balance. Plants need the carbon dioxide and water that are

waste products of the respiration in animals. Animals need the oxygen and ATP

that are the products op photosynthesis.

The Cell – Respiration and Photosynthesis

3217

Self Test

Matching

_____ 1. mitochondria a. the reaction that makes ATP

_____ 2. chloroplasts b. type of energy made during respiration

_____ 3. photosynthesis c. organelle that does respiration

_____ 4. respiration d. organelle that does photosynthesis

____ 5. ATP e. the reaction that makes glucose

True or False

_____ 1. Mitochondria need oxygen to function properly.

_____ 2. Mitochondria are found in all cells.

_____ 3. Chloroplasts are found in all cells.

_____ 4. Chloroplasts are only found in animal cells.

_____ 5. Chloroplasts are green.

_____ 6. Respiration creates ATP.

_____ 7. Respiration releases ATP as a waste product.

_____ 8. Respiration releases oxygen as a waste product.

_____ 9. Respiration occurs in the chloroplasts.

_____ 10. Respiration only occurs in plants.

_____ 11. Respiration uses water to make oxygen.

_____ 12. Photosynthesis occurs in the chloroplasts and mitochondria.

_____ 13. Photosynthesis releases oxygen as a waste product.

_____ 14. Photosynthesis only occurs in animals.

_____ 15. Photosynthesis uses water and carbon dioxide to make glucose.

_____ 16. Photosynthesis changes light energy into chemical energy.

_____ 17. Photosynthesis combines oxygen and carbon dioxide to make ATP.

_____ 18. ATP is a source of usable energy for the cells.

_____ 19. ATP is made during photosynthesis.

_____ 20. ATP is made during respiration.

_____ 21. ATP is a waste product of respiration and photosynthesis.

_____ 22. Photosynthesis and respiration form a cycle.

Fill in the Blank (some words used more than once) Mitochondria chloroplasts ATP

respiration photosynthesis

1. The ______________ provide a location for photosynthesis to take place.

2. _______________ and _______________ are 2 chemical reactions that

occur that involve energy capture and release.

3. In the process of _____________________, _____________ is the

usable form of energy that is created.

4. The green organelle that converts light energy into chemical energy is called

______________.

5. The _____________________ are found only in the cells of green plants,

but the ____________________ are found in all cells.

6. _________________ requires carbon dioxide and water to make glucose.

7. Cellular respiration occurs in the __________________________ and

creates the usable form of energy called _____________.

Answer the following

1. Write the simple reaction for photosynthesis.

2. Write the simple reaction for respiration.

3. Explain the function of the mitochondria.

4. Explain the function of the chloroplasts.

5. Based on what you have learned during this unit, explain why plants and

animals need each other.

The Cell – Respiration and Photosynthesis

3217 Answer Sheet

Question 1. What kinds of cells have chloroplasts and what to they do?

Question 2. What kinds of cells have mitochondria and what do they do?

Question 3. Explain why the sun is the source for all energy on Earth.

Question 4. What is the purpose of photosynthesis?

Question 5. What is the purpose of cellular respiration?

Question 6. Explain how photosynthesis and respiration are a cycle.