Unit 2: Cellular Respiration & Photosynthesis In other words, how organisms get energy to live!

ENERGY? Energy is the ability to do work Organisms get energy through food ◦ They either make their own food or eat food

ATP Stands for adenosine triphosphate Cells store their energy in the form of ATP Energy is released when bonds are broken LAW OF CONSERVATION OF ENERGY: Energy cannot be created or destroyed only CHANGE forms

MITOCHONDRIA VS. CHLOROPLASTS MITOCHONDRIACHLOROPLASTS Found in plant & animal cells Has own DNA Has double membrane Converts glucose into ATP CELLULAR RESPIRATION!!! Found only in plant cells Has own DNA Has double membrane Converts light energy into chemical energy (glucose) PHOTOSYNTHESIS!!!

REACTANTS VS PRODUCTS Reactants = starting materials in a chemical reaction Products = newly formed substances in a chemical reaction Circle the reactants and put a square around the products below… 2H 2 + O 2  2H 2 O

PHOTOSYNTHESIS --The process in which a plant makes food for itself using water, carbon dioxide and sunlight Reactants: CO 2 & H 2 O (Carbon dioxide & Water) Products: C 6 H 12 O 6 & O 2 (Glucose & Oxygen) CO 2 + H 2 O C 6 H 12 O 6 + O 2 Light energy

Photosynthesis… “…I thought it was cool until I realized that plants can eat the sun and poop out air.” -Jim Bugg

What do Plants do with the Glucose that they make? They use it to GROW!!!! They use it to make: ◦ Fats and oils for seeds ◦ Fructose for the fruit ◦ Cellulose for cell walls Glucose that isn’t used right away is stored It can also be used in respiration

FACTORS THAT AFFECT PHOTOSYNTHESIS --=SPEED UP PHOTOSYNTHESIS S L O W D O W N PHOTOSYNTHESIS Increased light Increased heat Increased carbon dioxide Increased water Decreased light Excessive light or heat Low temperatures Low water levels Low carbon dioxide levels Water pollution

FACTORS AFFECTING PHOTOSYNTHESIS (CONTINUED) As light intensity increases, so does photosynthesis up to a certain point, then photosynthesis levels off Rate of photosynthesis peaks at a certain temperature; anything beyond that temperature range doesn’t allow photosynthesis to increase Light intensity vs. rate of photosynthesis Temperature vs. rate of photosynthesis Light intensity Rate of photosynthesis Rate of photosynthesis Temperature

VIEW PHOTOSYNTHESIS et_chapter_group.htm?cin=2&ci=4&rg=anima ted_biology&at=animated_biology&npos=1&s pos=4&var=animated_biology

Photosynthesis Videos Basics: -Y Synopsis: pSE More in depth (Crash Course); c_k

PHOTOSYNTHESIS PROJECT!

CELLULAR RESPIRATION -The process in which cells break down food to release energy—uses oxygen and glucose to get energy and releases water and carbon dioxide as waste. Reactants: C 6 H 12 O 6 & O 2 (Glucose & Oxygen) Products: CO 2 & H 2 O ( Carbon dioxide & Water) C 6 H 12 O 6 + O 2 H 2 O + CO 2

FACTORS THAT AFFECT CELLULAR RESPIRATION --=SPEED UP CELLULAR RESPIRATION S L O W D O W N CELLULAR RESPIRATION Increased oxygen Increased glucose Increased temperature Decreased oxygen Decreased glucose Decreased temperature Extreme (hot or cold) temperatures could spell DEATH!!!!!

Photosythesis/cellular respiration graphic organizer

Cellular Respiration Lab!

Enzymes!

Energy in YOUR body It takes a lot of energy to digest food and use the oxygen in your blood. If you were to digest food outside of your body, it would require enough energy to create fire! So why isn’t your body ON FIRE when you digest your food? ENZYMES!

ENZYMES Made of proteins End in “ASE”. Examples: Catalase, lactase, sucrase, lipase They speed up chemical reactions by lowering the activation energy

Enzymes are specific: they only react with a certain substrate The substrate fits into the enzyme’s uniquely shaped Active Site (folds and pockets on the enzyme surface) **Enzyme Activity can be altered by temperature and pH.ENZYMES

High temperatures can cause enzymes not to function. Acids slow down a reaction Bases speed up a reactionENZYMES

Enzyme Lab! Catalase Apple Lab

Endothermic and Exothermic Reactions Happen in Photosynthesis and Cellular Respiration Energy can be stored in bonds or released by breaking bonds in chemical reactions There are two different types of reactions that will take in or let out energy: Endothermic and Exothermic

Endothermic Reactions Energy is absorbed IN. EXAMPLE: During Photosynthesis plants absorb sunlight IN

Exothermic Reactions Energy is released OUT. EXAMPLE: Cellular respiration releases energy

Watch a Demo Q6A8Hfw Q6A8Hfw

Endothermic/Exothermic Labs Catecholase Lab Cold/Hot packs Lab