ATP SYNTHASE COMPLEX ATP synthase is embedded in the inner membrane, together with the respiratory chain complexes. Several subunits of the protein form a ball-like shape arranged around an axis known as F1, which projects into the matrix and contains the phosphorylation mechanism. F1 is attached to a membrane protein complex known as F0, which […]
Inhibition of oxidative phosphorylation Read More »
Which of the following occurs in non-shivering thermogenesis? A) Glucose is oxidized to lactate B) Fatty acids uncouple oxidative phosphorylation C) ATP is spent on heat production D) Glycogen is excessively degraded E) Fatty acids are excessively oxidized The correct answer is C- Fatty acids uncouple oxidative phosphorylation Basic Concept The reduction of molecular oxygen
Non-shivering thermogenesis : uncoupling of oxidative phosphorylation Read More »
Q.1-Out of the following respiratory chain components indicate which one is a mobile carriers of electrons? a) Cytochrome oxidase b) NADH-Q reductase c) Ubiquinone d) Succinate dehydrogenase Q.2-Choose the incorrect statement about redox
Biological Oxidation-Multiple-choice questions- (part-1) Read More »
1. Dehydrogenases catalyze the transfer of hydrogen from one substrate to another in a coupled oxidation-reduction reaction.These dehydrogenases are specific for their substrates but often utilize common coenzymes or hydrogen carriers, e.g. NAD+. Which out of the following is not niacin ( NAD+) dependent dehydrogenase? a) Pyruvate dehydrogenase b) Glycerol-3-P dehydrogenase( Mitochondrial ) c) Glyceraldehyde-3-P
Biological oxidation and Electron Transport Chain (Mcqs) – part-2 Read More »
Q.1- Choose a site along the electron transport chain out of the following that is not coupled to ATP synthesis: a) NADH- coenzyme Q (CoQ) reductase b) Succinate-Co Q reductase c) Cytochrome bc1 reductase d) Cytochrome oxidase e) None of the above. Q.2- Choose a statement out of the following that best describes the uncouplers
Q.1- All of the following except one are NAD+ requiring enzymes – A. Acyl co A dehydrogenase B. Glyceraldehyde-3-P dehydrogenase C. Pyruvate dehydrogenase complex D. Malate dehydrogenase E. Lactate dehydrogenase Q.2- Which one of the following enzymes catalyzes substrate-level phosphorylation in the TCA cycle A. Malate dehydrogenase B. Succinate Thiokinase C. Succinate dehydrogenase D. Alpha
Electron transport chain and oxidative phosphorylation- Mcqs (set-1) Read More »
Q.1- If the mitochondria were blocked at the site of NADH oxidation and were treated with succinate as substrate, what would the P: O ratio is? A. Zero B. One less than normally produced by succinate C. Same as that normally produced by succinate D. One more than normally produced by succinate E. Higher than
Electron transport chain and oxidative phosphorylation- MCQs (Set-2) Read More »
Case Study An elderly couple was brought by ambulance to the emergency department after their daughter noticed that they were both acting “strangely.” The couple had been in good health prior to the weekend. Their daughter had gone out to spend the weekend with her friends. The couple had been snowed in at their house
Case study- CO Poisoning Read More »
An 18-year-old college student is brought to the emergency room unconscious, with a very high serum alcohol level. Alcohol metabolism can result in high NADH levels. When NADH enters the electron transport chain, which of the following is the correct order in which electron transfer occurs? a) NADH, coenzyme Q, cytochrome c, FMN, O2 b)
Electron Transport Chain – An Overview Read More »
A -8-year-old boy is seen by an ophthalmologist for difficulties in seeing in all visual fields as well as slow eye movements. The ophthalmologist finds pigmentary retinopathy and ophthalmoplegia. The child is suspected to have Kearns- Sayre syndrome, a disorder due to a mutation in complex II of ETC. The electron transport from which substance
Impaired electron flow through complex II Read More »
