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Peer Review

Tricarboxylic Acid Cycle (Krebs Cycle)

by Graham Kent


Overall Numeric Rating:

4.75 stars
Content Quality: 4.75 stars
Effectiveness: 4.75 stars
Ease of Use: 5 stars
Reviewed: Feb 02, 2014 by Biology Editorial Board
Overview: This object is part two of a three part series of animations of aerobic cellular respiration. It is a basic animation of the tricarboxylic acid cycle (aka, Krebs Cycle). It is accurate and keeps track of carbon dioxide, ATP, NDH and FADH2 molecules.
Type of Material: This is an animation/tutorial.
Recommended Uses: This object could be used as part of an in-class presentation or out of class assignment/review.
Technical Requirements: This site requires a current Internet browser with the Shockwave plugin.
Identify Major Learning Goals: There are no specific learning outcomes stated. However, the following outcomes apply:
  • Be able to explain the production of acetyl CoA and its role in the process
  • Be able to explain the production of carbon dioxide--disassembly of glucose into single carbon units
  • Be able to explain electron flow to NAD+
  • Accurately track inputs and outputs of this process
Target Student Population: This site is appropriate for high school (especially AP classes) and lower division college students.
Prerequisite Knowledge or Skills: The information at this site requires basic familiarity with mitochondria, aerobic cellular respiration, and oxidation/reduction reactions.

Evaluation and Observation

Content Quality

Rating: 4.75 stars
  • Inputs and outputs of the process accurately accounted for
  • The site is correct and visually appealing
  • Process broken down into easy to grasp, sequential stages
  • Molecular structures and enzymes not included for simplicity--easy for user to focus on the basics of the process
  • All parts of the process labeled correctly
  • Molecular structures and enzymes are not included for simplicity--however, this gives an overly simple view of the process
  • Understanding that the process is complex with multiple steps should be mentioned

Potential Effectiveness as a Teaching Tool

Rating: 4.75 stars
  • The site is easy to use and the text narration explains the animation very well
  • Animations are great ways for students to see the connections between different events in a process; this learning object does that very well
  • The object maintains an accounting of energy inputs and all sources of energy outputs through the process
  • Would be effective in a guided explanation; students can return to animation as needed
  • Would be effective as either an initial explanation or a review.
  • This learning object requires some additional information before viewing - although it does flow well with the other animations at the site

Ease of Use for Both Students and Faculty

Rating: 5 stars
  • The site is very easy to use; steps are well-explained
  • Student needs to simply click on each stage to view
  • Each stage can be viewed repeatedly as needed
  • The learning object has a very clean appearance that focuses student on the topic
  • There were no concerns about ease of use at the time of this review

Other Issues and Comments: Instructors will find this an excellent object for an overview of the process. In conjunction with the other parts it gives a complete overview with enough detail for beginning students. If you are at an upper college level course, it would be a good review but would need to be supplemented for complete understanding of the complexity.