Middle School Life Science: Cell Functions - Cellular Respiration — Flashcards

Glucose is the simple sugar that living things use to store and transport energy. Glucose is taken up by all of your cells. However, cells don't use the energy in glucose directly. They first need to release the energy and store it in ATP, or adenosine triphosphate. The smaller amount of energy stored in ATP is just right for fueling cell processes.    
The process in which your cells break down glucose, release the stored energy, and use the energy to make ATP is called cellular respiration. Each ATP molecule forms when a phosphate is added to ADP, or adenosine diphosphate.    
This requires energy, which is stored in the ATP molecule. When cells need energy, a phosphate can be removed from ATP. This releases the energy and forms ADP again.    
Cellular respiration involves many biochemical reactions. The overall process uses oxygen in addition to glucose.    
It releases carbon dioxide and water as waste products. Cellular respiration actually “burns” glucose for energy.    
However, it doesn't produce light or intense heat like burning a candle or log. Instead, it releases the energy slowly, in many small steps. The energy is used to form dozens of molecules of ATP.    
Cellular respiration begins in the cytoplasm of cells and is completed in a mitochondrion. A mitochondrion is a membrane-enclosed organelle in the cytoplasm. It is sometimes called the “powerhouse” of the cell because of its role in cellular respiration.