Author:
Tina B. Jones
Subject:
Biology
Material Type:
Module
Level:
Community College / Lower Division
Tags:
  • Biology 101
  • Cellular Respiration
  • NonMajors Biology
  • Tina B. Jones
    License:
    Creative Commons Attribution Non-Commercial Share Alike
    Language:
    English

    Cellular Respiration Summary

    Cellular Respiration Summary

    Overview

    Summary Diagram of the four major stages of cellular respiration.  

    Attributions:  Figure modified from OpenStax, Carbohydrate Metabolism. OpenStax CNX. Jan 5, 2015 http://cnx.org/contents/9d68abf9-4c2e-4ef7-88d1-c963c5c844b9@4.   NADH and FADH2 images modified from BQmUB2012173 [CC BY-SA 3.0 (https://creativecommons.org/licenses/by-sa/3.0)]. 

     

    Cellular Respiration Visual Summary

    Summary of cellular respiration.
    Visual summary of cellular respiration.

    The Metabolic enzymes catalyze catabolic reactions that break down carbohydrates contained in food. The energy released is used to power the cells and systems that make up your body. Excess or unutilized energy is stored as fat or glycogen for later use. Carbohydrate metabolism begins in the mouth, where the enzyme salivary amylase begins to break down complex sugars into monosaccharides. These can then be transported across the intestinal membrane into the bloodstream and then to body tissues. In the cells, glucose, a six-carbon sugar, is processed through a sequence of reactions into smaller sugars, and the energy stored inside the molecule is released. The first step of carbohydrate catabolism is glycolysis, which produces pyruvate, NADH, and ATP. Under anaerobic conditions, the pyruvate can be converted into lactate to keep glycolysis working. Under aerobic conditions, pyruvate enters the citric acid cycle, also called the Krebs cycle. In addition to ATP, the citric acid cycle produces high-energy FADH2 and NADH molecules, which provide electrons to the oxidative phosphorylation process that generates more high-energy ATP molecules. For each molecule of glucose that is processed in glycolysis, a net of 38 ATPs can be created by aerobic respiration.  ATP is used to power the cells and systems that make up your body.  Excess or unutilized energy is stored as fat or glycogen for later use. 

    Attributions

    Opening image:  CxOxS [CC BY 2.0 (https://creativecommons.org/licenses/by/2.0)]

    Cellular respiration diagram:  Modified from OpenStax, Carbohydrate Metabolism. OpenStax CNX. Jan 5, 2015 http://cnx.org/contents/9d68abf9-4c2e-4ef7-88d1-c963c5c844b9@4.   NADH and FADH2 images modified from BQmUB2012173 [CC BY-SA 3.0 (https://creativecommons.org/licenses/by-sa/3.0)].