March 29, What is cellular respiration? 2.What is fermentation?

Cellular Respiration Written Equation Glucose + Oxygen  Water + Carbon Dioxide + Energy Balanced Chemical Equation C 6 H 12 O 6 + 6O 2  6H 2 O + 6CO ATP Energy Transformation Takes energy of bonds in glucose and puts it into bonds of ATP (Adenosine TRIphosphate) ReactantsProducts

STEP 1: Glycolysis (glyco = sugar, lysis = break) In cytoplasm of cell No O 2 required – Anaerobic C 6 H 12 O 6  2 pyruvates (C 3 molecules) – AKA Pyruvic acid Use 2 ATP  2 ADP Make 4 ATP from 4 ADP OVERALL: Makes 2 ATP & 2 molecules for next step

STEP 1: Glycolysis NAD+ is an electron carrier, needed for step 3

STEP 2: Kreb’s Cycle (Citric Acid Cycle) In matrix of mitochondria – jelly like stuff, similar to cytoplasm Use 2 pyruvates from glycolysis Use O 2 – aerobic Makes CO 2 Makes 2 ATP from 2 ADP OVERALL: 6 CO 2 and 2 ATP made

STEP 2: Kreb’s Cycle FAD is an electron carrier, needed for step 3

STEP 3: Electron Transport Chain In cristae of mitochondria – inner membrane Series of reactions – H+ pumped out – e- move, generate energy Makes water Uses O 2 – Aerobic Makes 34 ATP from 34 ADP OVERALL: 6 H 2 O and 34 ATP

ATP ATP is energy “currency” – When energy is needed, ATP gets rid of a phosphate group and becomes ADP. – Breaking the bond to remove the P results in USABLE ENERGY released. – ADP can then be reused in process of cellular respiration!

PHOTOSYNTHESIS Written Equation Carbon Dioxide + Water + Sunlight  Glucose + Oxygen Balanced Chemical Equation 6H 2 O + 6CO 2 + energy  C 6 H 12 O 6 + 6O 2 OPPOSITE reaction of cell respiration! Energy Transformation Takes light energy and converts it to chemical energy (held in bonds of glucose!) Reactants Products

PHOTOSYNTHESIS Four requirements for this to occur: Carbon Dioxide Sunlight Chlorophyll (chemical in chloroplast) Water

STEP 1: Light Dependent Reactions In thylakoids – coin like stacks of chloroplast Light is absorbed by chlorophyll – all except green! Electron transport across thylakoid membrane 12 Water splits – Releases H+ ions for step 2 – releases O 2 (waste) Makes ATP for step 2 OVERALL: Makes H+ ions & ATP for step 2, O 2 waste

STEP 2: Light Independent Reactions Called Calvin Cycle Cannot occur if Step 1 doesn’t happen – Step 1 makes ATP to use as energy for this part! In stroma of chloroplast – Jelly like substance, like cytoplasm CO 2 comes in Releases 6 water Glucose made OVERALL: Makes Glucose (energy) & 6 Waters (waste)