Explain the concept of 'chemiosmosis' in oxidative phosphorylation

The process of chemiosmosis essentially addresses the issue of storing chemical energy into a specific bond. The conversion from chemical energy in the coenzymes, such as NADH and FADHto ATP cannot occur directly. Therefore energy from, NADH -> NAD+ + H+ + 2e- to phosphorylate ADP + Pi -> ATP, must be transferred through chemiosmosis. What is chemiosmosis? Chemiosmosis is very similar to osmosis which takes place with water moving through semipermeable membranes down its concentration gradient. The difference, of course, explaining the reason for 'chemi-' is that it involves ions moving down an electrochemical gradient. Inside the electron transport chain, referring to the initial equation, the electrons 'unloaded' undergo reduction-oxidation reactions to actively transport H+ ions to the intermembrane space. This creates an electrochemical gradient. Electro- denoting the difference in charge, and chemical signifying the differences in concentration. This gradient means that H+ diffuses down through selective channels which contain ATP synthase into the matrix, this movement of ions produces kinetic energy that is required to drive the formation of ATP (which is energetically unfavourable). Oxygen acts as the final electron acceptor - reacting with H+ to form water, this maintains the H+ electrochemical gradient required for chemiosmosis. 

Answered by Narut P. Biology tutor

2633 Views

See similar Biology A Level tutors

Related Biology A Level answers

All answers ▸

The genetic code is the sequence of bases in DNA, which is found in chromosomes and is made up of double stranded polynucleotides. Explain what is meant by the term “double-stranded polynucleotide” in relation to DNA.


What is a gene?


In humans, cystic fibrosis is caused by a recessive allele, f. A man and a woman are both heterozygous for the cystic fibrosis allele. What is the probability that they will produce a girl who has cystic fibrosis?


Explain why glucose is needed for the contraction of skeletal muscle.


We're here to help

contact us iconContact usWhatsapp logoMessage us on Whatsapptelephone icon+44 (0) 203 773 6020
Facebook logoInstagram logoLinkedIn logo

© MyTutorWeb Ltd 2013–2024

Terms & Conditions|Privacy Policy