What is the Krebs cycle?

Photosynthesis has four stages:

  1. Glycolysis. 

  2. The Link Reaction.

3. The Krebs Cycle. 

  1. Oxidative Phosphorylation. 

Photosynthesis converts glucose from food into energy that the body can use called ATP. In the first three steps, glucose is converted into a series of byproducts and molecules of reduced FAD and reduced NAD are released. The reduced FAD and reducd NAD are then used to drive ATP synthesis in step 4. 

Initially in the Krebs cycle, oxaloacetate (4 carbons) from the previous cycle combines with acetyl CoA (2 carbons) from the link reaction forming citrate (6 carbons.) For every glucose, the link reaction produces two moleucles of Acetyl CoA and so the Krebs cycle will occur twice. The steps then follow DeNa DeNa A Fa Na:

  • DeNa is the decarboxylation of citrate and production of reduced NAD and a 5 carbon compound and carbon dioxide.

  • The next DeNa is further decarboxylation, producing reduced NAD, regenerating oxaloacetate and making carbon dioxide.

  • A is the production of ATP from ADP and a phosphate ion.

  • Fa is the production of reduced FAD and Na is the production of reduced NAD.

MS
Answered by Megan S. Biology tutor

5626 Views

See similar Biology A Level tutors

Related Biology A Level answers

All answers ▸

Describe the process of transcription in detail.


Describe the processes which occur that allow synaptic transmission


Describe the stages of the mitotic cell cycle, explaining the appearance of cells at each stage.


How does the electron transport chain operate during respiration?


We're here to help

contact us iconContact ustelephone icon+44 (0) 203 773 6020
Facebook logoInstagram logoLinkedIn logo

© MyTutorWeb Ltd 2013–2025

Terms & Conditions|Privacy Policy
Cookie Preferences