ATP Production Overview

Welcome to this lesson on ATP production. Today you will be learning about the processes that occur in cellular respiration in order to produce ATP for a cell. Specifically, you will learn about:

1. Cellular Respiration Process
2. ATP as a Nucleotide

1. Cellular Respiration Process

Cellular respiration is the process in which ATP is produced. ATP stands for adenosine triphosphate, which is basically just an energy storage molecule used by cells.

Cellular Respiration

The process of converting molecules, such as proteins, fats and carbohydrates, into cellular energy and transferring that energy across cell membranes

Adenosine Triphosphate (ATP)

The primary form of energy used by cells to perform work, a nucleoside that has been phosphorylated by three phosphate groups

In this process, organic molecules, which are molecules that contain carbon, are broken down to produce ATP energy. ATP is the main source of energy used by cells. Substances or organic molecules, such as glucose, lipids, and proteins, can be broken down to make ATP.

The most important substance we're going to focus on is glucose. Glucose is used as an energy source faster than lipids and proteins; therefore, it has the potential to produce ATP rapidly. Extra steps have to happen in order for lipids and proteins to produce ATP.

There are three stages to cellular respiration.

1. Glycolysis

To initiate this process, a glucose molecule will enter the first stage of cellular respiration, which is glycolysis.

Glycolysis

The first step in cellular respiration; process of breaking down glucose into pyruvate that takes place in the cytoplasm of cells; is an anaerobic process

Glycolysis occurs in the cytoplasm of the cell. It's an anaerobic process, meaning that it does not require oxygen to occur. From glycolysis, we'll have some products produced that will be transferred into our other stages of cellular respiration.

2. Krebs Cycle

The next stage of cellular respiration is the Krebs cycle, which occurs in the mitochondria of the cell.

The Krebs Cycle

A series of chemical reactions used to generate energy, aerobically, that came from carbohydrates, fats and proteins

Mitochondria are cellular organelles found within our cells. The Krebs cycle occurs within the inner membrane of the mitochondria. The Krebs cycle is an aerobic process, which means it needs oxygen to occur. Some of the  products from the Krebs cycle will then be transferred into our next stage, which is the electron transport chain.

3. Electron Transport Chain

The electronic transport chain is the third stage of cellular respiration.

Electron Transport System

A series of reactions that couple electron donors with electron acceptors with the end result of transferring H⁺ ions across cell membranes to generate ATP

This also occurs in the inner compartment of the mitochondria, and is an aerobic process which requires oxygen.

At the end of the cellular respiration process, you end up with a net gain of 36 ATP molecules for every one glucose molecule that entered the process. Each of these different stages produces some ATP, but the vast majority of our ATP is produced in the electron transport chain.

2. ATP as a Nucleotide

ATP is actually a nucleotide, and thus contains a type of sugar. There is a ribose sugar attached to both the adenine base and the three phosphates. The energy is stored in the bond between the extra phosphate. ATP can give away or take on extra phosphates; when it has that extra phosphate on it, this is where stored energy is located.

This lesson has been an overview of ATP production. Specifically, you learned about the cellular respiration process, the three steps of which are glycolysis, the Krebs cycle, and the electron transport chain. Finally, you learned about ATP as a nucleotide.

Keep up the learning and have a great day!