Tag: living organisms and energy production
Questions Related to living organisms and energy production
Which of the following is a coenzyme?
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NAD
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NADP
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FAD
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All the above
Co-enzymes are organic compounds, are bound to the the enzyme to make the enzyme catalytically active, but their association with the enzyme is only transient, usually occurring during the course of catalysis. Co-enzymes serve as co-factors in a number of different enzyme catalyzed reactions. The essential chemical components of many coenzymes are vitamins, e.g., coenzyme nicotinamide adenine dinucleotide (NAD) and NADP contain the vitamin niacin; flavin adenine dinucleotide (FAD) is derived from riboflavin vitamin.
All of the following is true about oxidative phosphorylation, except
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It occurs in the inner membrane of the mitochondrion.
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It involves O$ _2$ as the final electron acceptor.
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It produces 2 ATPs for each FADH$ _2$.
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It can occur under anaerobic conditions.
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It involves a proton gradient.
Oxidative phosphorylation is an ATP generating process, which takes place in the inner membrane of mitochondria of aerobic organisms. In a generic sense, this process generates ATP via transferring electrons from $FADH _2$ or NADH via a series of complex carriers. Oxygen is a vital constituent of this process for its role as the final electron acceptor. Therefore, oxidative phosphorylation cannot take place in absence of oxygen. Hence, the correct answer is (D).
Which of the following is produced by oxidative phosphorylation?
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Oxygen and water
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NADH and ATP
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Pyruvate and NADPH
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Water and ATP
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Oxygen and NADH
The metabolic process of releasing energy from food can be termed as oxidative phosphorylation. It occurs in the mitochondria of eukaryotic cell. In this process, the electrons are transported through different carriers ultimately to the oxygen molecule. these electrons reduce oxygen to form water and release energy which converts ADP to ATP.
ATP is produced by oxidative phosphorylation in
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Glycolysis.
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Krebs cycle.
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Chemiosmosis.
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B and C only.
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A, B and C.
Electron carriers such as nicotinamide adenine dinucleotide (NAD) are used in energy capturing processes such as photosynthesis and respiration. They play a central role in the redox reactions that occur at the time of energy harvest from the carbon source.
What is the function of an oxidizing agent?
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Molecules that donate electrons.
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A molecule that becomes oxidized.
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A molecule that gains electrons.
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Molecules that combines with oxygen.
NAD$^+$ accepts electrons/H$^+$ released by water.
Enzymes required for phosphorylation are located in .......... of chloroplast.
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Peristromium
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Plastidome
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Stroma
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Quantosome
In chloroplast, the space enclosed by the inner membrane is called the stroma. It is colorless and homogeneous fluid. Phosphorylation is the process of addition of a phosphate group to ADP. The process of non-cyclic photophosphorylation takes place in the stroma lamellae with the help of enzymes present in it. Thus, the correct answer is option C.
Centre of phosphorylation is
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Ribosome
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Oxisome
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Peroxisome
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Spherosome.
- Oxidative phosphorylation refers to the process by which ATP molecules (energy currency) are produced in the mitochondria.
- ATP is produced by the transfer of electrons from NADH or FADH2 to oxygen molecule with the help of electron carriers.
- Oxysomes or F0-F1 particles refers to small round structures present within the folds of the cristae of the inner mitochondrial membrane.
- F0 and F1 particles are found in the inner mitochondrial region and are attached to the cristae and help in ATP production and oxidation.
Terminal oxidation comprises
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Synthesis of metabolic water
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Electron transport
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Oxidative phosphorylation
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All the above
The respiratory breakdown of glucose in the presence of oxygen is an oxidative process. During this process, several intermediates such as pyruvic acid, isocitric acid, succinic acid and oxalic acid are oxidized. Each oxidation step involves the release of 2 H which goes to reduce various coenzymes i.e. NAD+ and FAD. Reduced NAD+ and FAD released in the glycolysis and Krebs cycle finally reduce oxygen to water. This transfer of H+ and e- from NADH + H+ or FADH2 to oxygen is not a simple process and the direct transfer of electrons from coenzymes to oxygen is thermodynamically not possible. To facilitate this transfer, many intermediate cytochromes and other carriers are arranged in a series which transport electrons from NADH or FADH2 to oxygen. This sequence of electron carriers constitutes electron transport system. The electron transport proceeds from carriers that have low redox potential to those having high redox potential. The electron transport down to the energy gradient through electron transport system leads to the formation of ATP from ADP and inorganic phosphate. This generation of ATP is called oxidative phosphorylation.
Kreb's cycle takes place in
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Vesicles of E.R
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Mitochondria
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Dictyosomes
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Chloroplasts
Kreb cycle is also known as the citric acid cycle or tricarboxylic acid cycle takes place in the inner membrane of mitochondria. It occurs there because the necessary enzyme for the Krebs cycle, succinic dehydrogenase is only found in the inner membrane of the mitochondria.
When a pair of electrons from NADH+$H^+$ transported through respiratory ETS, results in the formation of
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2 ATPs
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4 ATPs
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3 ATPs
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5 ATPs
- Glycolysis and Krebs cycle yield certain reduced coenzymes like NADH+H+ and FADH2.
- ETS is metabolic pathway of electron transport that oxidizes these coenzymes to release energy from them.
- NADH+H+ gets oxidized at Complex I of ETS and as the electrons are transferred to other Complexes, it creates a proton gradient for ATP production. One NADH+H+ yields 3 ATPs and one FADH2 yields 2 ATPs.
- So the correct answer is '3 ATPs'.