What are the three stages process in the cellular respiration?

Answer 1

The three stages of cellular respiration are glycolysis, the Krebs Cycle, and the electron transport chain. The first stage happens in the cytoplasm while the last two occurs in the mitochondria.

Answer 2

the three main stages of cellular respiration are:

1. glycolysis - starts cellular respiration by breaking glucose down into pyruvate

(small amount of ATP is made as well)

2. citric acid cycle (krebs cycle) - completes the breakdown of glucose by decomposing a derivative of pyruvate to carbon dioxide. also, this stage supplies oxidative phosphorylation with electrons.

(small amount of ATP is made as well)

3. oxidative phosphorylation - mostly ATP is produced during this stage, more specifically chemiosmosis. electron transport chains are used during this stage, but that is not the sole purpose of oxidative phosphorylation.

Answer 3

1. Glycolysis:

Glycolysis involves the breaking down of glucose molecules from carbohydrates into molecules of pyruvate, which will continue on to the Krebs Cycle. This process occurs in the cytosol of the cell and can proceed regardless of the presence of oxygen. In the first stage of glycolysis, energy is actually used to phosphorylate the 6-carbon glucose molecule. This means that a phosphate is taken from ATP (which becomes ADP) and added to the glucose molecule. This addition of phosphate makes the molecule much more chemically reactive. The position of the glucose molecule is changed, so that it becomes its isomer, fructose. An enzyme then cuts the molecule apart, producing two 3-carbon molecules of pyruvate. Through several more steps, catalyzed by several different enzymes, the phosphate groups are removed and these pyruvate molecules are ready to enter the Krebs Cycle. The reactions of glycolysis produces a net gain of 2 ATP molecules, as well as a release of 2 water molecules and 2 NADH molecules (these are another type of energy-rich molecule)

2. The Krebs Cycle:

As pyruvate is being shuttled from the cytosol to the interior of the mitochondrion, a microenzyme removes one carbon and two oxygens from each molecule, producing Aceytl CoA. This two-carbon sugar that actually enters the Krebs Cycle. The Krebs Cycle is a series of steps, catalyzed by enzymes, which completely oxidize the Aceytl CoA molecule. The Krebs Cycle is an aerobic process, meaning it needs oxygen to function. Two complete turns of the Krebs Cycle must occur to produce: 4 carbon dioxide molecules, 6 NADH molecules, 2 ATP molecules and 2 FADH2 molecules (yet another energy-yielding molecule).

3. The Electron Transport Chain:

Very little energy has been produced during glycolysis and the Krebs Cycle. Most of the energy locked in the original glucose molecule will be released by the electron transport chain and oxidative phosphorylation. The electron transport chain is a network of electron-carrying located in the inner membrane of the mitochondrion. These proteins transfer electrons from one to another, down the chain, much in the way a bucket brigade passes buckets of water. These electrons will eventually be added, along with protons, to oxygen, which is the final electron acceptor. This produces water, but does not produce any ATP. The ATP is actually produced by a proton motive force. This force is a store of potential energy created by the gradient formed when hydrogens (protons) are moved across a biological membrane. Therefore, the electron transport chain merely produces a gradient through which ATP can be made (this is known as chemiosmosis). The electron transport chain produces the remaining 32-34 ATP.

Answer 4

• Glycolysis, occurring in the cytoplasm
• Kreb cycle, occurring within mitochondria
• electron transport chain, occurring at the membrane inside mitochondria.

Answer 5

- glycolysis - the production of pyruvate from glucose

- pyruvate decarboxylation - pyruvate is converted to acetyl-CoA and CO2

- Krebs (citric acid) cycle - acetyl-CoA is converted to a chain of substances, each of which generates NADPH and CO2

- oxidative phosphorylation - NADPH and oxygen are used to drive the production of ATP

Answer 6

1. Glycolysis

2. Krebs cycle

3. Electronic transport

Answer 7

1. glycolysis
2. krebs cycle
3. electron transport system

Answer 8

1. Glycolysis

2. Krebs Cycle

3. Electron Transport Chain

Answer 9

glycosis -> kreb's cycle -> electron transport chain