Chapter 2 The Cell in Action 2-2 Cell Energy

Essential Questions Describe photosynthesis and cellular respiration Compare cellular respiration with fermentation

Science Terms Photosynthesis Chlorophyll Cellular respiration Fermentation Equation for photosynthesis Equation for cellular respiration

Introduction: Why do people get hungry? It is their body’s way of telling them they need ENERGY!

From Sun to Cell: Where does nearly all energy for living things come from? The Sun!

From Sun to Cell: What is photosynthesis? This is the process where plants, algae, and some bacteria make food (sugar)from carbon dioxide (CO2), water (H2O), and sunlight. What other thing is made by photosynthesis? Oxygen (O2)

Photosynthesis: What structures within a plant allow it to make food from sunlight, water and carbon dioxide? Chloroplasts have a pigment called… Chlorophyll This pigment gives plants their green color!

Photosynthesis: What is the food that plants make called? Glucose (C6H12O6) What other thing is made by plants during photosynthesis? Oxygen (O2)

Photosynthesis: What is the equation for photosynthesis? 6CO2 + 6H20 + light energy C6H12O6 + 6O2 Carbon dioxide Oxygen Glucose Water MAKES

Getting Energy from Food: What are the two ways that animals can get energy from food? Cellular Respiration Fermentation Which one is better at providing more energy for the cell?

Cellular Respiration: What does the word “respiration” mean? “-tion” means PROCESS “respire” means BREATHE Process of Breathing!

Cellular Respiration: Where does cellular respiration happen? In every living cell What is cellular respiration? Cells breathing Cells combining oxygen with food to release energy (ATP) What else is made during cellular respiration? Carbon dioxide (CO2) and water (H2O)

Cellular Respiration: Where (specifically) in a cell does cellular respiration happen? Prokaryotes (bacteria): Cell membrane Eukaryotes (all other animals and fungi) Mitochondria

Cellular Respiration: What is the equation for cellular respiration? C6H12O6 + 6O2 6H20 + 6 CO2 + ATP Glucose Carbon dioxide Oxygen Water MAKES

Cellular Respiration: What do you notice about cellular respiration when you compare it to photosynthesis? Each process is the same EXCEPT… They are backwards from each other. If you read the equation for photosynthesis backwards, you get cellular respiration.

Connection Between Photosynthesis and Cellular Respiration: How are photosynthesis and cellular respiration related to each other? Each process provides what the other process needs Photosynthesis makes the glucose and oxygen needed for cellular respiration Cellular respiration makes the carbon dioxide and water needed for photosynthesis It’s a CYCLE!

Fermentation: When does fermentation happen? When there is NO oxygen present

Fermentation: When do humans use fermentation? When they exercise very hard and their muscles need more energy. Muscles use fermentation to make MORE energy but it also produces a substance called lactic acid This is the burning sensation you might get when you are tired from working out a lot

Fermentation: What other organisms use fermentation? Fungi (yeast!) Some bacteria