Cellular Respiration
Overview of Cellular Respiration the process that releases energy by breaking down glucose
and other food molecules in the presence of oxygen This is an aerobic process, meaning that it requires oxygen
Referred to as a metabolic pathway Metabolism: a cell’s chemical process
It occurs in the Mitochondria
Overall Chemical Equation
6O2 + C6H12O6 6CO2 + 6H2O + energy
Or
Oxygen + glucose carbon dioxide + water + energy
Structure of Mitochondria They are found in almost all eukaryotic cells.
It consists of two membranes, with a space between the inner and outer membranes.
The highly folded inner membrane encloses a thick fluid called the matrix.
Many enzymes and proteins are built into the membrane to allow for ATP production. The complex folding pattern allows for many sites where cellular
respiration can occur.
There are three process that make up cellular respiration in the presence of Oxygen.1. Glycolysis
2. Krebs Cycle
3. Electron Transport Chain
If it occurred all at once all the energy would be released at once, and most would be lost as heat and light. So it put into steps to release the energy in smaller amounts.
Cellular Respiration – use pg 222
Cytoplasm
Glycolysis – “splitting of sugar”
The process in which one molecule of glucose is broken in half, producing two molecules of pyruvic acid, a 3- carbon compound.First step of Cellular RespirationReleases only a small amount of energy.
The presence of oxygen determines which pathway is taken to release the energy
Occurs in the cytoplasm
1. The Process of GlycolysisGlucose
2 ATP
2 ADP
2 Pyruvic Acids
4 ADP
4 ATP
2 NAD+
2 NADH
2 Pyruvic Acids Aerobic Respiration
Anaerobic Respiration
Electron
Carrier
Remember this is the energy of the cell!
Uses Oxygen
Doesn’t use
Oxygen
Summary of Glycolysis
The original glucose molecule has been converted to two molecules of pyruvic acid.
Two ATP’s have been spent
And Four ATP’s have been produced and two NADPH
2.The Krebs Cycle
Also known as the citric acid cycleOccurs in the mitochondrial matrixPyruvic acid produced from glycolysis is used to
make a two carbon compound known as acetyl coenzyme A or acetyl CoA.
Acetyl CoA enters the cycle to produvce Carbon dioxideNADHATP
FADH2
Summary of the Krebs Cycle 2 ATP are produced
NADH and FADH2 carry electrons to the electron transport chain to make more energy
CO2 is released from the cell
3. Electron Transport Chain with ATP Synthase Action
The ETC used high energy electrons from the Kreb’s cycle to convert ADP to ATP.
Occurs in the inner membrane of the mitochondria and is composed of a series of carrier proteins.
Water is produced and released at the end of the ETC.
34 ATP are produced in the end
The Totals
Grand Total
Cellular Respiration without Oxygen
Fermentation is the process of releasing energy from food by producing ATP without Oxygen (anaerobic).
Occurs after Glycolysis
Two types Alcoholic fermentation
Lactic acid fermentation
Alcoholic Fermentation Yeast and few other microorganisms
Produces ethyl alcohol and carbon dioxide gas as wastes.
Lactic Acid Fermentation
Occurs in humans and other eukaryotesMuscle cramps are caused by a build up
of lactic acid When you exercise vigorously, the large muscles run out of oxygen
quickly.
Your muscles quickly produce ATP using lactic acid fermentation.
Lactic acid builds up which causes your muscles to ache.