Photosynthesis and Cellular Respiration

Photosynthesis & Respiration

What is Photosynthesis?

The process of photosynthesis is a chemical reaction.

It is the most important chemical reaction on our planet.

What is the Equation for the Chemical Reaction of

Photosynthesis?

What is the equation for the chemical reaction of

photosynthesis?

What is the equation for the chemical reaction of

photosynthesis?

Six molecules of carbon dioxide react with six molecules of water to form 1 molecule of

glucose and six molecules of oxygen.

Describe Photosynthesis

Describe Photosynthesis• The process of changing light energy to

chemical energy • Energy stored as sugar• Occurs in plants and some algae • Plants need light energy, CO2, and H2O • Takes place in the chloroplasts, using

chlorophyll, the green pigment in plants

What happens during photosynthesis?

What happens during photosynthesis?

• Plants capture light energy and use that energy to make glucose

• Sunlight provides the energy needed by chlorophyll to change molecules of carbon dioxide and water into glucose

• Oxygen is also released in this reaction

Why is this important to us?

Why is this important to us?

We cannot make our own food (glucose, energy), we must get our food from plants.

Plants are the first step in the food chain.

Why is this important to us?

The oxygen released during photosynthesis is necessary for all living things.

Pause and Think

• Which organelle in the cell does photosynthesis?

• What conversion of energy takes place?• What organisms do photosynthesis?

Pause and Think

• Which organelle in the cell does photosynthesis?

Chloroplast – creates products for energy• What conversion of energy takes place?Light energy (sunlight) to chemical energy

(glucose)• What organisms do photosynthesis? Autotrophs (auto means self anything that makes

its own food)

Learn more about photosynthesis at:

http://www.ftexploring.com/me/photosyn1.html

What is Cellular Respiration?

What is Cellular Respiration?

The release of chemical energy for use by cells.

What is Cellular Respiration?Once the energy that was in sunlight is

changed into chemical energy by photosynthesis, an organism has to transform the chemical energy into a a form that can be used by the organism.

This process is cellular respiration.

Describe Cellular Respiration

Describe Cellular Respiration• The breakdown of glucose molecules to

release energy

• Takes place in all living things

• Is a step by step process

What is the chemical equation for cellular respiration?

What is the chemical equation for cellular respiration?

Pause and Think

• Where in the cell does cellular respiration take place?

• How do chloroplast and mitochondria compare?

• What is the energy source that is created?

Pause and Think

• Where in the cell does cellular respiration take place?

Mitochondria• How do chloroplast and mitochondria

compare?They both make energy• What is the energy source that is created?Glucose is converted into ATP

Read how photosynthesis & respiration are related:

http://www.usoe.k12.ut.us/curr/science/sciber00/8th/energy/sciber/photosyn.htm

Anaerobic Cellular Respiration

• Notice that Aerobic Cellular Respiration requires oxygen. This is what your body does for normal everyday function.

• Anaerobic takes place with out oxygen.• There are two types

– Lactic Acid (animal cells under strenuous activity)

– Alcoholic Fermentation (takes place in yeasts)

• Lactic Acid

» ATP + lactic acid

• Alcoholic Fermentation

» ATP + ethanol

Pause and Think

• What is the main difference between aerobic and anaerobic respiration?

• Which produces more energy?• How do lactic acid and alcoholic

fermentation differ?

Pause and Think• What is the main difference between aerobic and

anaerobic respiration?Aerobic requires oxygen and glucose as a reactants Anaerobic only uses glucose no oxygen• Which produces more energy?Aerobic • How do lactic acid and alcoholic fermentation differ? Lactic Acid takes place in animals during strenuous

physical activity.Alcoholic fermenation takes place in yeast and

produces ethanol

1. The chemical equation for photosynthesis is shown below.

6CO 2 + 6H 2 O + sunlight! C 6 H 12 O 6 + 6O 2 Which of the following products is the chemical compound that contains most of the converted energy from the reaction? SC.912.L.18.7a)CO2b)H2Oc)O2d)C6H12O6

2. Cathy placed a sample of yeast in a test tube containing a solution of glucose. A process called fermentation releases energy from the glucose. Fermentation is similar to respiration but releases energy from carbohydrates without using oxygen as a reactant. How will the composition of the air in the test tube change as the yeast interacts with the glucose? SC.912.L.18.8 a)The oxygen level will increase.b)The glucose level will increase.c)The amount of yeast will increase.d)The carbon dioxide level will increase.

Practice Test Questions

3. Four substances are important for both photosynthesis and cellular respiration: oxygen, glucose, carbon dioxide, and water. What is the best explanation for how both processes use these substances? SC.912.L.18.9a)Photosynthesis uses carbon dioxide and oxygen to make water; respiration uses glucose and oxygen to make carbon dioxide and water.b)Photosynthesis uses carbon dioxide and water to make glucose and oxygen; respiration uses oxygen and water to make glucose and carbon dioxide.c)Photosynthesis uses glucose and carbon dioxide to make water and oxygen; respiration uses glucose and oxygen to make water and carbon dioxide.d)Photosynthesis uses carbon dioxide and water to make glucose and oxygen; respiration uses glucose and oxygen to make carbon dioxide and water.

4. Earth’s systems depend upon each other to exchange energy and matter. The processes that drive this exchange are similarly interrelated. How are photosynthesis and cellular respiration interrelated? SC.912.L.18.9• a)Glucose produced during photosynthesis is used in cellular respiration to capture energy.b)Glucose produced during cellular respiration is used in photosynthesis to capture energy.c)Glucose produced during cellular respiration is used in photosynthesis to generate energy.d)Glucose produced during photosynthesis is used in cellular respiration to generate energy.

5. The diagram below represents part of the process of cellular respiration. Energy is released and made available for metabolic activities at which step? SC.912.18.10

• 

• a) Step 1b) Step 2c) Both Step 1 and 2d) Neither Step 1 or 2

 6. ATP is a compound that is synthesized when which occurs? SC.912.18.10 

a) Chemical bonds between carbon atoms are formed in photosynthesis.b) Energy stored in chemical bonds is released during cellular respirationc) Energy stored in nitrogen is released forming amino acidsd) Digestive enzymes break amino acids in smaller parts.