Cellular Respiration Continuing Chapter 8 SOL Page 228

Cellular Respiration Living organisms obtain energy by breaking down organic molecules Living organisms obtain energy by breaking down organic molecules

Cellular Respiration Organisms obtain energy Organisms obtain energy Function is to harvest the electrons from carbon compounds and use that energy to make ATP for the body to use Function is to harvest the electrons from carbon compounds and use that energy to make ATP for the body to use

Cellular Respiration Equation How does this compare to photosynthesis? How does this compare to photosynthesis?

2 types of Respiration AEROBIC RESPIRATION: oxygen must be present AEROBIC RESPIRATION: oxygen must be present ANAEROBIC RESPIRATION: oxygen does not need to be present ANAEROBIC RESPIRATION: oxygen does not need to be present

Diagram of the flow of CR This must be memorized This must be memorized A box represents a process A box represents a process A cloud represents a product A cloud represents a product What is Glycolysis? What is Glycolysis? What is Pyruvic acid or pyruvate? What is Pyruvic acid or pyruvate?

2 Parts to Cellular Respiration When using Oxygen Glycolysis Glycolysis Aerobic Respiration Aerobic Respiration Krebs cycle Krebs cycle Electron Transport Chain Electron Transport Chain

Glycolysis Glucose is broken down in the cytoplasm It is anaerobic which means it does not need oxygen to be present This is an enzyme-assisted process that will break down glucose into the molecule of pyruvate 2 ATP are needed to start Glycolysis Remember Glucose is made of 6 carbons

Glycolysis It is broken down by ATP into two 3-carbon compounds with a phosphate attached on both sides This 3-Carbon compound is called pyruvate and produces 4 ATP The end result is the Net gain of 2 ATP 2 pyruvates 2 NADH are produced (they are electron energy carriers)

GLYCOLYSIS STAGE #2

KREBS CYCLE AKA Citric Acid Cycle or Tricarboxylic Acid Cycle Oxygen is present thus the body goes thru aerobic respiration This occurs in the mitochondria of eukaryotes

KREBS CYCLE In this stage the pyruvate is converted into a 2 carbon-compound called Acetyl-CoA This cycle is completed 2 times since there were 2 pyruvates This will produce 8 NADH (electron energy carrier) 2 FADH 2 (electron energy carrier) 2 ATP 6 CO 2

Remember it must go thru the cycle 2 times

Animation of Krebs Cycle animations/content/cellularrespiration.html animations/content/cellularrespiration.html animations/content/cellularrespiration.html animations/content/cellularrespiration.html

Electron Transport Chain the last step of aerobic respiration most of the ATP is produced in this process NADH & FADH2 release hydrogen ions to create the energy the hydrogen ions move along the mitochondrial membrane Hydrogen ions are pumped back and forth on the membrane transforming FADH2 into FAD and NADH into NAD+ This causes more hydrogen ions to be released and to be pumped along the membrane

Electron Transport Chain This creates 32 ATP Some of the hydrogen ions unite with oxygen to create water which is released by the body End result is 32 ATP Water

End Products of Aerobic Respiration HOW MANY ATP HAVE BEEN MADE? HOW MANY ATP HAVE BEEN MADE? Glycolysis produced: 2 ATP Krebs Cycle produced: 2 ATP ETC produced: 32 ATP TOTAL ATP: 36 ATP from 1 glucose molecule TOTAL ATP: 36 ATP from 1 glucose molecule Why does this make sense? 1)our bodies need energy 2)2) 36 ATP per glucose will give the organism plenty of energy to do what it needs TRIVIA FACT: the body uses about 1 million ATP molecules per second !!!

Prokaryotic Aerobic Cellular Respiration No mitochondria No mitochondria Must use cell membrane instead Must use cell membrane instead Results in 38 ATP Results in 38 ATP

NO OXYGEN!!!! Anaerobic Respiration: no oxygen or a low amount Fermentation: occurs in the cytoplasm and regenerates the cells supply of NAD+ while producing a small amount of ATP Need to find a way to replenish NAD+ to keep Glycolysis going 2 types Lactic Acid Fermentation Alcoholic Fermentation

Lactic Acid Fermentation Glycolysis occurs first bringing pyruvate to the mitochondria in the presence of no/little oxygen Skeletal muscles produce lactic acid when the body cannot supply enough oxygen This happens during strenuous/vigorous exercise in your muscle cells when you are pushing your body to the limit This causes your muscles to become fatigue and sore

Lactic Acid Fermentation Your body during strenuous exercise has taken pyruvate and converted it into lactic acid When your body is able to replenish the oxygen, the lactic acid will be converted back to pyruvate and the body will go through regular cellular respiration Some microorganism use this pathway to create many foods like cheese, sour cream and yogurt

Alcoholic Fermentation Glycolysis occurs first Pyruvate is broken down into ethyl alcohol and CO2 CO2 is released this occurs in yeast a type of unicellular organism (fungus) and bacterial cells the yeast and bacteria help to prepare bread and beverages

ANAEROBIC RESPIRATION Results How many ATP have been produced? How many ATP have been produced? Glycolysis produced: 2 ATP Lactic Acid Fermentation produced : 0 ATP Total amount: 2 ATP How many ATP have been produced? How many ATP have been produced? Glycolysis produced: 2 ATP Alcoholic Fermentation produced: 0 ATP Total amount: 2 ATP Why does this make sense? … The body is not using oxygen efficiently to break down pyruvate to give the body enough energy

Website animations/content/cellularrespiration.html animations/content/cellularrespiration.html animations/content/cellularrespiration.html animations/content/cellularrespiration.html SOL Review SOL Review Here are questions on Respiration and Photosynthesis Here are questions on Respiration and Photosynthesis

Question What happens if you drink a soft drink containing 22 grams of sugar, how come you do not gain the weight of the sugar? The sugar will be broken down into mostly CO2 H atoms will unite with O2 to produce water Water eliminated by breathing, urination, and some kept by the cell for other processes If the sugar is not needed for energy then it will be stored as glycogen and lipids

Essential Questions What are the stages of cellular respiration? What is the role of the electron carriers in cellular respiration? How many ATP are produced in: Glycolysis, Krebs Cycle, ECT, all of aerobic respiration? Vocabulary: anaerobic respiration, aerobic respiration, glycolysis, Krebs cycle, fermentation