Respuesta :
Cyanide interrupts the electron transporter chain. Pyruvate concentration DOES NOT CHANGE. NADH concentration INCREASES in the matrix, and H+ concentration DECREASES in the intermembrane space.
-----------------------------------
Let us firts make a quick revision of aerobic respiration.
Through cellular respiration, cells degrade organic compounds and produce energy.
Aerobic respiration takes place in three steps:
1) Glycolysis is the first step of cellular respiration. It occurs in the cytoplasm, and its final product is Pyruvate.
2) The Krebs cycle takes place in the mitochondria matrix.
3) The electron transporter chain is placed in the internal mitochondrial membrane.
*******************
We already know that cyanide affects the electron transporter chain. So, let us focus on its functioning under normal conditions and under the cyanide effect.
⇒ Under normal conditions,
• ATP is produced at the end of the electron transporter chain.
• The electron transporter chain constitutes a series of enzymatic reactions to release and save energy for the correct functioning of the organism.
• Along the chain, there are four proteinic complexes in the membrane, I, II, III, and IV, that contain the electrons transporters and the enzymes necessary to catalyze the electrons' transference from one complex to the other.
• Cytochrome oxidase (P450) is one of the enzymes involved in this electron transport.
• NADH and FADH2 provide electrons to the chain.
• While electrons move along the chain, complexes I, III, and IV pump protons to the intermembrane space.
• At the end of the chain, water molecules and ATP are produced.
⇒ Under cyanide effect,
• Ion cyanide inhibits cellular respiration.
• Cyanide binds to the ferric ion of cytochrome oxidase.
• Cyanide-ferric binding inactivates the enzyme and blocks electron transference.
• The chain is interrupted. Hence,
- NADH and FADH2 stop providing electrons,
- complexes I, II, and IV stop pumping protons to the intermembrane space,
- there is no oxygen consumption and
- no ATP production.
• Since muscles do not get to have ATP as a source of energy, they weaken.
• The interruption of the electron transporter chain produces an anaerobic state that could be culminating.
*************************
Now, let us answer the question
- Pyruvate concentration ⇒ NO CHANGE
Since Pyruvate is produced in the cytoplasm, it is not affected by cyanide. Remember that cyanide only affects the electron transporter chain.
- NADH concentration ⇒ INCREASE
Since NADH provides electrons to the chain, and Cyanide interrupts electron transport, there is an accumulation of NADH molecules in the matrix.
- Intermembrane H+ concentration ⇒ DECREASE
Since the electron transporter chain is interrupted, no electrons are being carried, and no protons are being pumped to the intermembrane space.
--------------------------------------------
Related link: https://brainly.com/question/13975046?referrer=searchResults
https://brainly.com/question/24372542?referrer=searchResults
