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Right OPTION is (C) pantothenic acid

The explanation is: Coenzyme A is an ORGANIC compound DERIVED from pantothenic acid. Pantothenic acid is a B-group vitamin and is water soluble. The ACETYL group from the decarboxylation of pyruvate is transferred to coenzyme A, making it acetyl CoA.

The correct option is (c) 2 GTPs

Best EXPLANATION: The IMPORT of cargo or MOLECULE inside the nucleus is an active TRANSPORT. This is because the whole of import cycle needs the energy from the hydrolysis of two GUANOSINE triphosphate (GTP) molecules.

The correct choice is (a) Kremer BODIES

The explanation: Kremer bodies, also known as Promyelocytic leukaemia bodies (PML bodies) are SPHERICAL matrix-associated nuclear bodies. Their specific role in not YET known though their role in ongenesis and viral infection is unavoidable. They MAY be a site for RNA TRANSCRIPTION, storage of rRNAs of other transcriptional activity.

Right option is (b) 2

Easiest explanation: Proton motive FORCE is a measure of electrochemical GRADIENT. Because the translocation of protons across the membrane lead to a difference of hydrogen ion concentration and a difference of CHARGE, the energy PRESENT in both components of the proton electrochemical gradient are combined and expressed as proton motive force.

The CORRECT answer is (a) 5′ capping, 3′ polyadenylation and RNA splicing

Explanation: After transcription, the pre-mRNA is modified to produce matured mRNA. The MODIFICATION of mRNA INCLUDES the following- 5′ methul GUANOSINE capping that protects the mRNA from RNases, 3′ polyadenylation and splicing of the introns of pre-mRNA.

Correct answer is (a) oxaloacetate

The best I can EXPLAIN: Acetyl CoA is a 2 CARBON COMPOUND that combines with oxaloacetate which is a 4 carbon compound to form a 6 carbon compound, citrate. The reaction is CATALYZED by citrate synthase.

Right choice is (d) 4

Explanation: There are FOUR such a reaction in which electron is TRANSFERRED from substrate to electron accepting enzyme. In three of these, NAD+ is reduced to NADH and in one FAD REDUCES to FADH2.

The correct answer is (b) False

The explanation: The INNER mitochondrial MEMBRANE must remain highly impermeable to PROTONS otherwise the GRADIENT established by electron transport would be quickly dissipated by the leakage of protons BACK into the matrix.

Right option is (B) more than 30

For EXPLANATION: The end products of glycolysis, pyruvate and NADH can be metabolized in the mitochondria in presence of OXYGEN. This process can generate more than 30 additional MOLECULES of ATP.

The correct option is (d) ISOMERIZATION

Easiest explanation: In the TCA CYCLE, aconitase is RESPONSIBLE for isomerization of citrate to isocitrate. Isocitrate is further oxidized by isocitrate DEHYDROGENASE to FORM alpha-ketoglutarate.

The correct choice is (b) 2

Explanation: Since each MOLECULE of glucose GIVES off two PYRUVATE molecules through the PROCESS of glycolysis, the CYCLE operates twice for each molecule of glucose.

Right choice is (b) False

Easiest explanation: Only a SMALL fraction of free energy available in glucose is available to cell for the net SYNTHESIS of TWO ATP MOLECULES during glycolysis. Most of the energy is stored in pyruvate.

The correct option is (c) mRNA

Explanation: All and cellular RNAs such as tRNAs, rRNAs, snRNAs and miRNAs except mRNA are DEPENDENT on RanGTP for their transport outside the NUCLEUS. Conserved mRNA export FACTORS such as Mex67/Tap (LARGE subunit) and Mtr2/p15 are required for mRNA transport. In higher eukaryotes, mRNA recruits the protein TREX for spliced mRNA sequences.

Correct CHOICE is (a) perform splicing of snRNPs

For explanation I would say: Nuclear speckles, also CALLED as splicing speckles are subnuclear structures that are enriched in pre-messenger RNA splicing factors and are located in the interchromatin regions of the nucleoplasm. The splicing factors HELP in the splicing of snRNPs and other splicing proteins that are necessary for pre-mRNA PROCESSING.

Correct option is (a) 220

To explain: The approximate proton motive force that an actively RESPIRING mitochondrion generates ACROSS its inner membrane is 220 mV. In mammalian mitochondria, 80 PERCENT is represented by the VOLTAGE component and 20 percent by proton concentration.

Correct CHOICE is (a) 2

To explain I would say: Glucose is FIRST phosphorylated at the expense of one ATP molecule, rearranging to form FRUCTOSE phosphate and then PHOSPHORYLATION takes place again LEADING to a total of two phosphate groups attached to the fructose chain.

Right answer is (b) Leptomycin B

Explanation: CRM1 is an exportin which binds to the Nuclear Export Sequence (NES) of protein molecules DESTINES to be transported out of the nucleus. The export PROCESS with exportin CRM1 can be STOPPED by Leptomycin B.

The CORRECT OPTION is (c) TCA cycle

Easy explanation: The TCA cycle is also KNOWN as the Krebs cycle after the name of British biochemist Hans KREB who elucidated the pathway in 1930s.

The correct option is (b) 2

The best explanation: TWO ATP molecules are FORMED per molecule of glucose oxidized.Along with ATP, in the net reaction two PYRUVATE molecules and two molecules of water are also formed.

Correct answer is (d) tRNA processing

The best explanation: Cajal bodies re sub-nuclear compact structures with diameter between 0.2-2.0 micrometers, depending on the species. They are mainly RELATED to RNA SYNTHESIS and helps in RNA-related metabolic processes such as snRNPs biogenesis, MATURATION and RECYCLING, histone mRNA processing and telomere maintenance.

The correct option is (c) LEM-3

The best I can explain: The nuclear lamina is mostly COMPOSED of lamin proteins. The cytosolic lamin proteins which face the cytoplasm, such as EMERIN and Nesprin BINDS to the cytoskeleton to provide structural RIGIDITY. Lamins such as LEM3 are FOUND inside nucleus and form the nucleoplasmic veil and bind to the intra-nuclear chromatin.

Right answer is (a) ACETYL COA

Best explanation: The metabolites of TCA cycle are also the same compounds generated by other catabolic PROCESSES in the CELL. For instance, Acetyl CoA is also an important end product of DISASSEMBLY of fatty acids.

The CORRECT choice is (c) 36

To explain I would say: By complete catabolism of one MOLECULE of glucose by glycolysis and TCA cycle, 36 molecules of adenosine triphosphate (ATP) are formed.

The CORRECT option is (a) Acetyl CoA

To elaborate: Acetyl CoA is present in the mitochondrion which binds with the pyruvate and undergoes the TCA cycle. 2 ATP molecules are generated for one molecule of oxygen; as a result of mitochondrial METABOLISM.

Right option is (d) They are present during interphase and absent during mitosis.

Explanation: PARASPECKLES are irregular shaped sub-nuclear COMPARTMENTS which are transcription dependent.Paraspeckles disappear in absence of RNA polemerase II transcription and all of its associated protein components form a CRESCENT shaped perinucleolar cap in the nucleolus. However, paraspeckles are present during the interphase and all the STAGES of mitosis except the telophase.

Right OPTION is (d) cytosol

For EXPLANATION I would SAY: The process of converting pyruvate to CELLULAR energy molecules is known as the Krebs cycle. This process decarboxylates pyruvate using enzymes present in the mitochondrial matrix.

Correct option is (a) Importin-alpha

Easiest explanation: The molecules that contain NUCLEUS LOCALIZATION Signal (NLS) sequence, are immediately ushered into the nucleus through nucleopore. The first step of this transport involves binding of importin-alpha to the NLS sequence, which then acts as a BRIDGE for the ATTACHMENT of importin-beta.

Correct answer is (b) Absence of nucleus leads to INCREASED space for haemoglobin that carries molecular oxygen

The BEST I can explain: RED blood cells (RBCs) present in HUMAN blood stream do not contain nucleus. Absence of nucleus leads to more space for stuffing of haemoglobin that carries molecular oxygen. This thus increases the oxygen-carrying capacity in blood. If the nucleus was present, haemoglobin CONTENT will be limited around the periphery. Furthermore, due to absence of nucleus, RBCs contain a disk-like depression that increases the surface are for haemoglobin content.

Correct option is (C) permeability

To explain: The contribution made by ELECTRIC potential VERSUS pH GRADIENT is determined by the permeability of the membrane. For example if at a particular instance, membrane is permeable to Cl- ions the electric potential gradient is reduced without affecting the PROTON gradient.

The correct option is (c) CAS

Best explanation: Once the complex composed of importin-alpha—importin-beta—molecule enters the NUCLEUS, the importin-alpha and importin-beta has to be removed. RANGTP BINDS to Importin-beta and displaces it from the complex. Then the Cellular Apoptosis Susceptibility (CAS) protein which is an exportin and is bound to RanGTP, displaces Importin-alpha from the molecule with NLS sequence.

Right CHOICE is (a) Myocytes

To explain I would SAY: Multinucleated cells have multiple nucleus. In humans, SKELETAL muscle cells which are also known as myocytes, become multinucleated during development. The results in the arrangement of nuclei near the PERIPHERY of the skeletal muscle cells and thus, allowing maximum intracellular space for MYOFIBRILS.

Correct option is (b) 2

Easy explanation: ACETYL COA is a 2 carbon compound. From oxidation of pyruvate (by the pyruvate dehydrogenase) which is a 3 carbon compound, acetyl CoA is formed with the release of ONE molecule of CO2 and NADH each.

The correct option is (b) TCA cycle

For explanation I would SAY: Mitochondrion is the SITE for FINAL energy-conserving steps in metabolism. The energy providing macromolecules POLYSACCHARIDES, fats and proteins break down into the metabolites of TCA cycle.

Correct OPTION is (c) INNER membrane

The explanation is: The inner membrane of mitochondrion MAINTAINS an ionic GRADIENT across its inner membrane to drive energy requiring ACTIVITIES mainly ATP synthesis.

Right answer is (a) True

To explain: The reduced coenzymes FADH2 and NADH are produced during the TCA cycle. Mitochondria are not able to import the NADH from cytosol and there are TWO mechanisms that ALLOW ELECTRONS to reach mitochondrial electron transport chain and be used for ATP production.

The correct answer is (a) 1 GTP

To explain: The export of protein molecules from nucleus to cytoplasm is done due to the presence of Nuclear Export Sequence (NES). NES of the protein MOLECULE can bind with an exportin and RanGTP to form a heterotrimeric complex. This complex is then transported outside nucleus by ACTIVE TRANSPORT as it REQUIRES the hydrolysis of ONE GTP molecule.

The correct OPTION is (c) mitochondrion

For EXPLANATION I would say: Other than hydrolysis of ATP, mitochondrion has alternate sources of energy one of which is proton MOTIVE force. It drives the uptake of ADP in EXCHANGE of ATP; and can also be used to pull calcium ions into the mitochondrion.

Correct choice is (a) aerobic, anaerobic

The best I can EXPLAIN: Tricarboxylic ACID (TCA) CYCLE is an aerobic oxidative METABOLISM whereas glycolysis is anaerobic oxidative metabolism.

The correct choice is (C) 10

To explain: A total of 10 reactions are present in a GLYCOLYTIC pathway. The first step is phosphorylation of glucose at the expense of one adenosine triphosphate MOLECULE.

Right option is (a) True

For explanation: Oxidative PHOSPHORYLATION is a PROCESS where the energy RELEASED by ELECTRONS removed during substrate OXIDATION drives the formation of ATP. Substrate-level phosphorylation involves the transfer of phosphate group from substrate to ADP, leading to generation of ATP.

Correct option is (c) Coilin

To explain: Cajal bodies re sub-nuclear compact structures with DIAMETER between 0.2-2.0 micrometers, depending on the species. Under ELECTRON microscope, the appear as small TANGLES threads with a DENSE dictricution of the Coilin protein. They are BOUND to the nucleolus by coilin proteins.