Photosynthesis vs Respiration Where Does Energy Come From

Photosynthesis vs. Respiration

Where Does Energy Come From? n n n Energy is stored in food!!! ONLY Plants are autotrophs—they make their own food from sunlight. Animals are heterotrophs- cannot make their own food, must eat plants for energy.

Why Energy? n Energy- ability to cause change All cell functions need energy! To move, to breath, to reproduce, to digest, etc. n All energy in living things is as chemical bonds n Main energy source for all life = THE SUN n

The energy molecules ATP (adenosine tri-phosphate) Made in mitochondria n

ATP vs. ADP n Break chemical bonds = RELEASE energy n Adding chemical bonds = STORE energy

Photosynthesis Reaction/Equation 6 CO 2 + 6 H 2 O +sunlight energy = C 6 H 12 O 6 + 6 O 2 trapped by chlorophyll Carbon Dioxide + Water + Sunlight = Glucose + Oxygen n 2 phases (parts): n n Light -dependent- needs light, oxygen released Light- independent- no light needed, makes sugar

Photosynthesis n n Photo: light Synthesis: make something Process by which plant cells use light energy to make food n n Where: in plants, chloroplasts Who: Chlorophyll- pigment that traps sun’s light energy in plants ONLY

Cellular Respiration n The opposite of photosynthesis! Instead of making food, we break down food plants made to release energy Takes place in mitochondria of all living things C 6 H 12 O 6 + 6 O 2 = 6 CO 2 + 6 H 2 O + ATP

Bellringer 11/112/09 1. Write the equation for photosynthesis 2. Write the equation for cellular respiration! Use your notes from Friday/Monday! Reminders: HW #10 due Fri! LAB FEE NOW! Time’s Up! Minutes 30 Seconds 314259 10 6 Minute 7 8

Cellular Respiration Stages n 3 Stages (parts): n Glycolysis- anaerobic n Citric Acid Cycle (Krebs Cycle)- aerobic n ETC (Electron Transport Chain)- aerobic

Aerobic respiration energy produced using oxygen n Anaerobic respiration - also called Fermentation - energy without oxygen n

Fermentation 1. Lactic Acid Fermentationenergy without oxygen, ex: muscles while running 2. Alcoholic Fermentation yeast, bacteria, this is how we make beer, cheese, bread, vinegar, wine and cider

Photosynthesis vs. Respiration Photosynthesis Food made Respiration Food broken down Energy from sunlight stored Stored energy in glucose released CO 2 taken in CO 2 and H 2 O given off O 2 given off In the presence of chlorophyll- plants only O 2 taken in Occurs in all living organisms Light needed In Chloroplasts No light needed In Mitochondria

Photosynthesis vs. Respiration