<img src="https://d5nxst8fruw4z.cloudfront.net/atrk.gif?account=iA1Pi1a8Dy00ym" style="display:none" height="1" width="1" alt="" />
Skip Navigation
Our Terms of Use (click here to view) have changed. By continuing to use this site, you are agreeing to our new Terms of Use.

1.16: Types of Biochemical Reactions

Difficulty Level: At Grade Created by: CK-12
Atoms Practice
Estimated4 minsto complete
Practice Types of Biochemical Reactions
Estimated4 minsto complete
Practice Now
Turn In

What do you get when you cross biology and chemistry?

Hummingbirds, with their tiny bodies and high levels of activity, have the highest metabolic rates of any animals — roughly a dozen times that of a pigeon and a hundred times that of an elephant. The metabolic rate, or rate of metabolism, has to do with the amount of energy the organism uses. And that energy is used to drive the chemical reactions in cells — or the biochemical reactions. And, of course, it is all the biochemical reactions that allow the cells function properly, and maintain life.

Biochemical Reactions

Biochemical reactions are chemical reactions that take place inside the cells of living things. The field of biochemistry demonstrates that knowledge of chemistry as well as biology is needed to understand fully the life processes of organisms at the level of the cell. The sum of all the biochemical reactions in an organism is called metabolism. It includes both exothermic and endothermic reactions.

Types of Biochemical Reactions

Exothermic reactions in organisms are called catabolic reactions. These reactions break down molecules into smaller units and release energy. An example of a catabolic reaction is the breakdown of glucose, which releases energy that cells need to carry out life processes. Endothermic reactions in organisms are called anabolic reactions. These reactions build up bigger molecules from smaller ones. An example of an anabolic reaction is the joining of amino acids to form a protein. Which type of reactions—catabolic or anabolic—do you think occur when your body digests food?


  • Biochemical reactions are chemical reactions that take place inside the cells of organisms.


Use this resource to answer the questions that follow.

  • http://www.hippocampus.org/Biology Biology for AP* Search: Enzymes and Metabolism: Overview
  1. What are kinetics and reaction rates?
  2. What is an energy diagram?
  3. Does a spontaneous reaction always result in products with a lower amount of free energy than the reactants?
  4. Do all reactions need a certain amount of activation energy?
  5. What lowers the amount of activation energy needed?


1. What are biochemical reactions? What is an example of a biochemical reaction?

Notes/Highlights Having trouble? Report an issue.

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


anabolic reaction

Endothermic reaction in organisms; reactions that build up bigger molecules from smaller ones.

biochemical reaction

Chemical reaction that occurs inside the cells of living things.


Field combining biology and chemistry; focuses on the chemistry of living organisms.

catabolic reaction

Exothermic reaction in organisms; reactions that break down molecules into smaller units.

Image Attributions

Show Hide Details
Difficulty Level:
At Grade
Date Created:
Feb 24, 2012
Last Modified:
Sep 04, 2016
Files can only be attached to the latest version of Modality
Please wait...
Please wait...
Image Detail
Sizes: Medium | Original