Aerobic respiration is the process of breaking down the food that comes into a cell using oxygen to help power that process. A cell would do this in order to generate a lot of ATP now the basic chemical reaction is C6H12O6 that's glucose plus 6O2 and that's oxygen gas yielding 6 carbon dioxide gas molecules which eventually diffuse out of the cell and 6 water molecules and a bucket load of energy. Generally it produces 6 ATP molecules for every glucose molecule that goes in.
Now aerobic respiration can be used for other molecules besides glucose but we usually focus on glucose it's one of the primary fuel sources and then once you understand that you just say okay, we'll make some tiny modifications and see how we can plug in proteins and other molecules. Now like I said it produces 36 ATP but compared to anaerobic respiration without using oxygen it's slow and it does have that whole requirement about oxygen which is one of those annoying things I mean you hold your breath for a couple of minutes and you get kind of dizzy. Well, let's a look at how this happens the key organelle of aerobic respiration is the mitochondria.
Now the first step in the break down of glucose is glycolysis which happens in the cytosol or the cytoplasm of the cell. But once it's done then the molecules enter the mitochondria where it undergoes the series of chemical reactions that are called the Krebs cycle sometimes it's also called the tricarboxylic acid cycle or the citric acid cycle depending on which text book you use.
Finally it ends with a process known as the electron transport system. Let's take a closer look at how this happens, so here we see glucose which is a 6 carbon molecule that's what the little blue marbles here represent. And in going through the process known as glycolysis which means literally sugar splitting the glucose is split in half into a pair of 3 carbon molecules called pyruvate. This gives you some high energy electrons they were helping hold this together and those are sent off here to the electron transport system inside the mitochondria. You do get a little bit of ATP here but it's only 2 so not a big deal. The pyruvate eventually makes it's way into the inner portion of the mitochondria called the matrix where it undergoes the series of chemical reactions known as the Krebs cycle.
Again we get a little bit of energy molecules in the form of ATP or actually technically it's GTP and this is where we finally start releasing all of the carbon dioxides as they come flying out those carbons used to be in the glucose. We get a whole bunch more of these NADHs again they're high energy electron carriers and a couple of FADH 2 molecules. These are carrier molecules they literally carry electrons that have a lot of energy off to the molecules that make up something cleverly known as the electron transport system. The electron transport system uses the energy all of those high energy electrons to do something called proton pumping or hydrogen ion transport.
And what they do is they shove the hydrogen ions across the membrane then as those hydrogen ions make their way back across the membrane just like water going from one side of a dam through the other can drive a hydro dynamic electric generator. Here we see the high energy electrons have shoved the hydrogen ions across then as they go back they make bucket loads of ATP. Now we need some place to dump those high energy electrons and that's what oxygen is for. We dump the high energy electrons onto the O2 molecules they pick up a couple of hydrogen ions and become water. That's aerobic respiration.
Aerobic respiration takes place in the presence of oxygen, produces a large amount of energy. Carbon dioxide and water are produced as the waste products.
Anaerobic respiration takes place without the use of oxygen, produces small amounts of energy. Alcohol or lactic acid or other compounds are produced as waste products depending on the kind of cells that are active.
The type of energy needed for a long-distance race versus a short-term wrestling match can also help explain the difference between aerobic and anaerobic respiration. For a long-distance race, aerobic respiration takes place producing a large amount of energy. For a short-term wrestling match, anaerobic respiration takes place and will produce small bursts of energy.
The race is a cardio exercise, and the heart must maintain a steady rate of about 60 to 80% of its maximum, and there must be enough oxygen to sustain muscle power. On the other hand, an intense, short workout like a wrestling match requires the heart rate to increase to more than 80% of its maximum, and there must be enough oxygen for an immediate source of power.
In brief, aerobic respiration allows for long-term energy needs, and anaerobic for short-term energy needs. Of course, most sports and activities use a combination of aerobic and anaerobic respiration.
There are also other technical differences between aerobic and anaerobic respiration. For aerobic, the cells involved include those in most organisms and body cells; however, anaerobic may occur in muscle cells and red blood cells, and is some types of bacteria and yeast.
Lactic acid is produced during Anaerobic, and none is produced during aerobic. A high amount of energy is produced in aerobic respiration with 38 glucose molecules, and low energy with only 2 glucose molecules during anaerobic.
In addition, the reactants for aerobic respiration is both oxygen and glucose, yet for anaerobic the reactant is just glucose. The reaction site in the cell for aerobic is in the cytoplasm or mitochondria, and just in the cytoplasm for anaerobic respiration.
Both aerobic and anaerobic respiration involves a first stage called glycolysis. The additional stage in anaerobic is fermentation, but in aerobic there is the Krebs cycle and electron transfer chain. Finally, combustion is complete in aerobic respiration, and incomplete during anaerobic respiration.
In summary, when thinking of aerobic respiration, relate it to aerobic exercises, which involves the need for a large amount of energy over a long time period. Oxygen is present and carbon dioxide and water is produced as waste products. For anaerobic, short burst and small amounts of energy produced, oxygen is not present, lactic acid and other compounds are produced as waste products depending on the kind of active cells.