생명과학5. 독극물

DNP는 1940년대 의사들이 환자의 몸무게를 감소시키기 위해 처방하기도 했던 약물이다. DNP가 몸무게를 감소시키는 원리에 대해 서술하라.(Hint : DNP 처방 환자가 사망하는 일이 발생하면서 DNP의 사용이 금지되었다. 세포호흡의 산화적 인산화 단계를 고려하라.)

 

로테논과 사이안화물 및 일산화탄소가 독성을 나타내는 원리와 올리고마이신이 독성을 나타내는 원리를 서술하라.

 

 

5.01. 전자전달계

During oxidative phosphorylation, chemiosmosis couples electron transport to ATP synthesis

• Following glycolysis and the citric acid cycle, NADH and FADH2 account for most of the energy extracted from food
• These two electron carriers donate electrons to the electron transport chain, which powers ATP synthesis via oxidative phosphorylation

The Pathway of Electron Transport

• The electron transport chain is in the inner membrane (cristae) of the mitochondrion
• Most of the chain’s components are proteins, which exist in multiprotein complexes
• The carriers alternate reduced and oxidized states as they accept and donate electrons
• Electrons drop in free energy as they go down the chain and are finally passed to O2, forming H2O

• Electrons are transferred from NADH or FADH2 to the electron transport chain
• Electrons are passed through a number of proteins including cytochromes (each with an iron atom) to O2
• The electron transport chain generates no ATP directly
• It breaks the large free-energy drop from food to O2 into smaller steps that release energy in manageable amounts

The Energy-Coupling Mechanism

• Electron transfer in the electron transport chain causes proteins to pump H+ from the mitochondrial matrix to the intermembrane space
• H+ then moves back across the membrane, passing through the protein complex, ATP synthase
• ATP synthase uses the exergonic flow of H+ to drive phosphorylation of ATP
• This is an example of chemiosmosis, the use of energy in a H+ gradient to drive cellular work

 

2021.10.25 - [Science/생명과학] - 생명과학12. 탄소고정

생명과학12. 탄소고정

참고