<img src="https://d5nxst8fruw4z.cloudfront.net/atrk.gif?account=iA1Pi1a8Dy00ym" style="display:none" height="1" width="1" alt="" />
Dismiss
Skip Navigation

2.15: Connecting Cellular Respiration and Photosynthesis

Difficulty Level: At Grade Created by: CK-12
Atoms Practice
Estimated3 minsto complete
%
Progress
Practice Connecting Cellular Respiration and Photosynthesis
 
 
 
MEMORY METER
This indicates how strong in your memory this concept is
Practice
Progress
Estimated3 minsto complete
%
Estimated3 minsto complete
%
Practice Now
MEMORY METER
This indicates how strong in your memory this concept is
Turn In

How do trees help you breathe?

Recall that trees release oxygen as a byproduct of photosynthesis. And you need oxygen to breathe. Do you know why? So your cells can perform cellular respiration.

Connecting Cellular Respiration and Photosynthesis

Photosynthesis and cellular respiration are connected through an important relationship. This relationship enables life to survive as we know it. The products of one process are the reactants of the other. Notice that the equation for cellular respiration is the direct opposite of photosynthesis:

  • Cellular Respiration: C6H12O6 + 6O2 → 6CO2 + 6H2O
  • Photosynthesis: 6CO2 + 6H2O → C6H12O6+ 6O2

Photosynthesis makes the glucose that is used in cellular respiration to make ATP. The glucose is then turned back into carbon dioxide, which is used in photosynthesis. While water is broken down to form oxygen during photosynthesis, in cellular respiration oxygen is combined with hydrogen to form water. While photosynthesis requires carbon dioxide and releases oxygen, cellular respiration requires oxygen and releases carbon dioxide. It is the released oxygen that is used by us and most other organisms for cellular respiration. We breathe in that oxygen, which is carried through our blood to all our cells. In our cells, oxygen allows cellular respiration to proceed. Cellular respiration works best in the presence of oxygen. Without oxygen, much less ATP would be produced.

Cellular respiration and photosynthesis are important parts of the carbon cycle. The carbon cycle is the pathways through which carbon is recycled in the biosphere. While cellular respiration releases carbon dioxide into the environment, photosynthesis pulls carbon dioxide out of the atmosphere. The exchange of carbon dioxide and oxygen during photosynthesis (Figure below) and cellular respiration worldwide helps to keep atmospheric oxygen and carbon dioxide at stable levels.

Cellular respiration and photosynthesis are direct opposite reactions. Some of the ATP made in the mitochondria is used as energy for work, and some is lost to the environment as heat.

Vocabulary

  • carbon cycle: Pathways through which carbon is recycled through the biosphere.
  • cellular respiration: Process of breaking down glucose to obtain energy in the form of ATP.
  • photosynthesis: Process by which specific organisms (including all plants) use the sun's energy to make their own food from carbon dioxide and water; process that converts the energy of the sun, or solar energy, into carbohydrates, a type of chemical energy.
  • products: End results of a chemical reaction.
  • reactants: Molecules that come together to start a chemical reaction.

Summary

  • The equation for cellular respiration is the direct opposite of photosynthesis.
  • The exchange of carbon dioxide and oxygen thorough photosynthesis or cellular respiration worldwide helps to keep atmospheric oxygen and carbon dioxide at stable levels.

Practice

Use the resource below to answer the questions that follow.

  1. What is needed for photosynthesis to occur? Be as specific and complete as you can in your answer.
  2. What is needed for cellular respiration to occur? Be as specific and complete as you can in your answer.
  3. Do autotrophs need to carry out cellular respiration? Why or why not?

Review

  1. How are the equations for photosynthesis and cellular respiration related?
  2. What keeps atmospheric oxygen and carbon dioxide at stable levels?

    Notes/Highlights Having trouble? Report an issue.

    Color Highlighted Text Notes
    Please to create your own Highlights / Notes
    Show More

    Vocabulary

    carbon cycle

    Pathways through which carbon is recycled through the biosphere.

    cellular respiration

    Process of breaking down glucose to obtain energy in the form of ATP.

    photosynthesis

    Process by which specific organisms (including all plants) use the sun's energy to make their own food from carbon dioxide and water; process that converts the energy of the sun, or solar energy, into carbohydrates, a type of chemical energy.

    products

    End results of a chemical reaction.

    reactants

    Molecules that come together to start a chemical reaction.

    Image Attributions

    Show Hide Details
    Description
    Difficulty Level:
    At Grade
    Grades:
    7 , 8
    Date Created:
    Nov 29, 2012
    Last Modified:
    Aug 30, 2016
    Files can only be attached to the latest version of Modality
    Please wait...
    Please wait...
    Image Detail
    Sizes: Medium | Original
     
    SCI.LSC.236.3.L.1
    Here
    Add Note
    Please to create your own Highlights / Notes