{"id":88256,"date":"2021-06-22T12:43:00","date_gmt":"2021-06-22T07:13:00","guid":{"rendered":"https:\/\/kseebsolutions.guru\/?p=88256"},"modified":"2021-07-01T20:28:36","modified_gmt":"2021-07-01T14:58:36","slug":"1st-puc-biology-question-bank-chapter-14","status":"publish","type":"post","link":"https:\/\/kseebsolutions.guru\/1st-puc-biology-question-bank-chapter-14\/","title":{"rendered":"1st PUC Biology Question Bank Chapter 14 Respiration in Plants"},"content":{"rendered":"

Karnataka 1st PUC Biology Question Bank Chapter 14 Respiration in Plants<\/h2>\n

1st PUC Biology Respiration in Plants One Marks Questions and Answers<\/h3>\n

Question 1.
\nName the site of glycolysis.
\nAnswer:
\nCytoplasm of the cell.<\/p>\n

Question 2.
\nHow many molecules of ATP are formed for every molecule of glucose during aerobic respiration?
\nAnswer:
\n38 ATP molecules<\/p>\n

\"1st<\/p>\n

Question 3.
\nWhat is the RQ value for carbohydrates?
\nAnswer:
\nOne.<\/p>\n

Question 4.
\nWhat is the RQ value for organic acids?
\nAnswer:
\nMore than one.<\/p>\n

Question 5.
\nName the compound that reacts with Acetyl CoA to form Citric acid during Kreb\u2019s cycle.
\nAnswer:
\nOxalo acetic acid.<\/p>\n

Question 6.
\nWhat is Pasteur\u2019s effect?
\nAnswer:
\nSudden change from anaerobic respiration to aerobic respiration due to the availability of oxygen in facultative anaerobes is called Pasteur\u2019s effect.<\/p>\n

\"1st<\/p>\n

Question 7.
\nDefine Respiratory quotient.
\nAnswer:
\nIt is defined as the ratio of volume of CO2<\/sub> liberated to the volume of oxygen utilised. Volume of CO, liberated
\n\"1st<\/p>\n

Question 8.
\nIn which cell organelle Kreb\u2019s cycle occurs?
\nAnswer:
\nMitochondria.<\/p>\n

Question 9.
\nName the phase which is common for both aerobic and anaerobic respiration?
\nAnswer:
\nGlycolysis.<\/p>\n

Question 10.
\nWhat are respiratory substrates? Name the most common respiratory substrate.
\nAnswer:
\nRaw materials of cellular respiration which can yield ATT on break down are called respiratory substrates. e.g: Carbohydrates and proteins.<\/p>\n

\"1st<\/p>\n

1st PUC Biology Respiration in Plants Two Marks Questions and Answers<\/h3>\n

Question 1.
\nDefine aerobic cellular respiration?
\nAnswer:
\nAerobic respiration can be defined as a step wise complete oxidation of food molecules, into simple inorganic compounds, in the presence of molecular oxygen with the release of energy.
\nC6<\/sub>H12<\/sub>O6<\/sub> + 6O2<\/sub> \u2192 6CO2<\/sub> + 6H2<\/sub>O + 686 kcal.\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 .<\/p>\n

Question 2.
\nWhat is fermentation? Give the equation for alcoholic fermentation.
\nAnswer:
\nIt can be defined as a process of incomplete breaking down of food molecules into Ethyl alcohol, C02<\/sub> and lactic acid by the activity of micro organisms or enzymes in the absence of molecular oxygen.
\nEquation for alcoholic fermentation is
\n\"1st<\/p>\n

Question 3.
\nDefine respiratory quotient. Give the RQ value of carbohydrates.
\nAnswer:
\n\"1st
\nRQ value for carbohydrates is one.<\/p>\n

Question 4.
\nDefine RQ. What is its value for fats?
\nAnswer:
\nRespiratory quotient (R-Q)
\nRespiratory quotient can be defined as the ratio of volume of CO2<\/sub> released, to O2<\/sub> consumed
\nto break one molecule of respiratory substrate completely.
\n\\(\\mathrm{RQ}=\\frac{\\text { Volume of } \\mathrm{CO}_{2} \\text { released }}{\\text { Volume of } \\mathrm{O}_{2} \\text { consumed }}\\)
\nR.Q of carbohydrate is 1.
\nRQ of proteins is 0.7
\nRQ of fats is 0.71
\nRQ of organic acid is more than 1(1.2 or 1.3).<\/p>\n

\"1st<\/p>\n

Question 5.
\nWhat is oxidative phosphorylation?
\nAnswer:
\nOxidative phosphorylation or electron transport-linked phosphorylation or terminal oxidation is the metabolic pathway in which cells use enzymes to oxidize nutrients, thereby releasing the chemical energy stored within the nutrients in order to produce adenosine triphosphate.<\/p>\n

Question 7.
\nDifferentiate aerobic cellular respiration from anaerobic ceUular respiration.
\nAnswer:<\/p>\n\n\n\n\n\n\n\n\n
Aerobic C.R<\/strong><\/td>\nAnaerobic C.R<\/strong><\/td>\n<\/tr>\n
1. Occurs in the presence of molecular oxygen.<\/td>\n1. Occurs in the absence of oxygen.<\/td>\n<\/tr>\n
2. Centered in mitochondria and cytoplasm,<\/td>\n2. Centered in cytoplasm.<\/td>\n<\/tr>\n
3. Glucose is completely oxidised into CO2 <\/sub>and H2<\/sub>O.<\/td>\n3. Glucose is incompletely oxidised into C2<\/sub>H5<\/sub>OH and CO2<\/sub>.<\/td>\n<\/tr>\n
4. Generates 38 ATPs per glucose.<\/td>\n4. Generates only 2 ATPs per glucose.<\/td>\n<\/tr>\n
5. Occurs in a great majority of organisms called anaerobes.<\/td>\n5. Occurs in only a few of organisms called aerobes.<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n

\"1st<\/h3>\n

1st PUC Biology Respiration in Plants Five Marks Questions and Answers<\/h3>\n

Question 1.
\nGive the schematic representation of glycolysis?
\nAnswer:
\nIt occurs in cytoplasm of the cell.
\nIt is an enzymatic reaction, thus temperature sensitive.
\nIt is a common reaction for both aerobic and anaerobic respiration.<\/p>\n

\"1st<\/p>\n

Question 2.
\nWhat are the main steps in aerobic respiration? Where does it take place?
\nAnswer:
\nAerobic respiration: It is a completely oxygen dependent process, and occurs in the presence of molecular oxygen. It is centered in mitochondria. Here glucose is completely oxidised into CO2<\/sub> and water. It generates 38 ATP per glucose, and hence more efficient energy releasing process. It occurs in the majorily of living organisms called aerobes.
\nC6<\/sub> H12<\/sub> O6<\/sub>+ 6O2<\/sub> \u2192 6CO2<\/sub> + 6H2<\/sub>O+ 686kcal + 38ATP mol<\/p>\n

\"1st<\/p>\n

Question 3.
\nGive the schematic representation of an overall view of Krebs cycle.
\nAnswer:
\n\"1st<\/p>\n

Note: To account for two molecules of acetyl CoA produced from 1 molecule of glucose the entire reaction has to be multiplied by two.<\/p>\n

Bioenergetics:
\n1. Number of ATPs produced = 2
\n2. Number of NADH2 produced = 6 (6*3=18ATPs)
\n3. Number ofFADH2 produced = 2 (2*2=4 ATPs)
\nThe total yield of ATPs = 24
\nNote:- Efficiency of Krebs cycle along with its predatory reaction is 30 ATPs.<\/p>\n

\"1st<\/p>\n

Question 4.
\nExplain ETS.
\nAnswer:
\nIt occurs on the inner mitochondrial membrane, using electron acceptor molecules. In this step the products of glycolysis and kreb\u2019s cycle i.e.. NADH2<\/sub>, and FADH2<\/sub> pass along the electron transport chain of mitochondria. The energy held by their hydrogen atoms is released, and utilised in the synthesis of ATPs. This includes two processes.<\/p>\n

    \n
  • Oxidation of NADH2<\/sub> and FADH2<\/sub> (i.e., removal of hydrogen).<\/li>\n
  • Addition of phosphate to ADP to form ATP. Hence these processes are together known as oxidative phosphorylation.<\/li>\n<\/ul>\n

    The electron carriers, Flavin mononucleotide, ubiquinone, cytochromes (cyt b6<\/sub>, cyt c, cyt a, cyt a3<\/sub>) are found on the surface of cristae. As the electrons flow along the chain, the carriers get alternately oxidised and then reduced. Hence these reactions are called redox reactions. Finally hydrogen atoms are given to molecular oxygen to form H2<\/sub>O which is the by product. Continuous supply of oxygen is required to carry this out.<\/p>\n

    The energy released during electron flow is used in the synthesis of ATPs from ADPs, with the addition of inorganic phosphate.<\/p>\n

      \n
    • Thus both oxidation and phosphorylation occur simultaneously.<\/li>\n
    • During the oxidation of NADH2<\/sub>, three molecules of ATPs are synthesised, and during oxidation of FADH2<\/sub> two ATPs are synthesised.<\/li>\n<\/ul>\n

      Question 5.
      \nDiscuss \u2018The respiratory pathway is an amphibolic pathway.\u201d
      \nAnswer:
      \nSince respiration involves break down of organic compounds, it has been considered as a catabolic process, and the respiratory pathway as a catabolic process. But as different substances enter the pathway as respiratory substrates, and certain intermediate of the respiratory pathway are also vithdrawn for synthesis of other compounds.<\/p>\n

      For e.g: Fatty acids would be broken down into acetyl Co<\/sub>A for entering the pathway, acetyl C,A from the respiratory pathway will be taken out if fatty acids have to be synthesised. Similarly the respiratory pathway, intermediates are involved in the synthesis of proteins, because respiratory pathway involves both anabolism and catabolism it is called as an amphibolic pathway.
      \n\"1st<\/p>\n

      \"1st<\/p>\n

      Question 6.
      \nGive the schematic representation of glycolysis:
      \nAnswer:
      \nIt occurs in cytoplasm of the cell.
      \nIt is an enzymatic reaction, thus temperature sensitive.
      \nIt is a common reaction for both aerobic and anaerobic respiration.
      \n\"1st<\/p>\n

      \"1st<\/p>\n

      Question 7.
      \nGive the schematic representation of Kreb’s cycle with its preparatory reaction?
      \nAnswer:
      \n\"1st<\/p>\n

      Note: To account for two molecules of acetyl CoA produced from 1 molecule of glucose the entire reaction has to be multiplied by two.<\/p>\n

      Bioenergetics:
      \n1. Number of ATPs produced = 2
      \n2. Number of NADH2 produced = 6 (6*3=18ATPs)
      \n3. Number ofFADH2 produced = 2 (2*2=4 ATPs)
      \nThe total yield of ATPs = 24
      \nNote:- Efficiency of Krebs cycle along with its predatory reaction is 30 ATPs.<\/p>\n

      \"1st<\/p>\n

      Question 8.
      \nDescribe the mechanism of fermentation in the presence of yeast and lactic acid bacteria?
      \nAnswer:
      \nThe first step of anaerobic respiration is glycolysis, in which glucose is incompletely oxidised to 2 pyruvic acid molecules with 2 ATP and 2NADH2<\/sub> formed as by-products.<\/p>\n

      Pyruvic acid formed is used for alcoholic fermentation or lactic acid fermentation. In alcoholic fermentation, the pyruvic acid is first decarboxylated to acetaldehyde liberating CO2<\/sub>. Later acetaldehyde is reduced to ethyl alcohol by NADH2<\/sub> of glycolysis. This process occurs in anaerobes like yeast and bacteria.<\/p>\n

      In lactic acid fermentation, the pyruvic acid is directly reduced to lactic acid by NADH2<\/sub> of glycolysis. NO CO2<\/sub> is liberated. It occurs in lacto bacilli, and skeletal muscles.
      \n\"1st<\/p>\n

      1st PUC Biology Respiration in Plants Text Book Questions and Answers<\/h3>\n
        \n
      • Respiration is an essentially an intracellular oxidative catabolic process in which, the potential energy of food molecules is converted into kinetic energy namely ATP, along with heat energy as a by product.<\/li>\n<\/ul>\n

        Based on whether the process uses oxygen or not, it is of two types namely,<\/p>\n

          \n
        • Aerobic respiration.<\/li>\n
        • Anaerobic respiration.<\/li>\n<\/ul>\n

          Aerobic respiration: It is a completely oxygen dependent process, and occurs in the presence of molecular oxygen. It is centered in mitochondria. Here glucose is completely oxidised into CO2<\/sub> and water. It generates 38 ATP per glucose, and hence more efficient energy releasing process. It occurs in the majority of living organisms called
          \nC6<\/sub> H12<\/sub>O6<\/sub>+ 6O2<\/sub>\u00a0 \u2192 6CO2<\/sub> + 6H2<\/sub>O+ 686kcal + 38ATP mol<\/p>\n

          Anaerobic respiration: It is an oxygen independent process and occurs in the absdmoli oxygen. It is centered in general cytoplasm. Here glucose is incompletely oxidised into ethyl alcohol, and CO2<\/sub> or lactic acid generates only 2 ATPs per glucose molecule, and hence less efficient energy releasing process. It occurs only in a few organisms like bacteria, yeast etc.<\/p>\n

          \"1st<\/p>\n

          Mechanism of aerobic respiration:\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 ‘<\/p>\n

          Stepwise breakdown of respiratory substances to CO2<\/sub> and H2<\/sub>O in presence of O2<\/sub> is re\u00adferred to as aerobic respiration. This involves the following four steps:<\/p>\n

            \n
          • Oxidative decarboxylation.<\/li>\n
          • Krebs cycle \/ TCA cycle \/ Citric acid cycle.<\/li>\n
          • Electron transport system \/ Terminal oxidation \/ Oxidative phosphorylation.<\/li>\n<\/ul>\n

            1. Glycolysis:<\/p>\n

              \n
            • It is the stepwise breakdown of glucose into 3 carbon (CH3<\/sub>COCOOH) pyruvic acid with the production of NADH2<\/sub>, and ATP. It occurs in the cytoplasm of the cell. It does not require the oxygen.<\/li>\n
            • It is a common step for both aerobic, and anaerobic cellular respiration.<\/li>\n<\/ul>\n

              Steps:<\/p>\n

                \n
              1. Glucose is phosphorylated by 1 ATP to form glucose 6 phosphate catalysed by hexokinase.<\/li>\n
              2. Glucose 6 phosphate is isomerised to fructose 6 phosphate, catalysed by isomerase.<\/li>\n
              3. Fructose -6- phosphate is phosphorylated by another ATP to form fructose 1,6 diphosphate, catalysed by phosphoffucto kinase.<\/li>\n
              4. Fructose 1,6 diphosphate cleaves to form 2 molecules of 3- phosphoglyceraldehyde which isomerize into dihydroxy acetone phosphate by a reversible reaction.<\/li>\n
              5. The two molecules of triose phosphates undergo phosphorylation followed by dehydrogenation to form two molecules of 1,3 Diphosphoglyceric acid, and catalysed by PGAL dehydrogenase, more NADH2<\/sub> is formed.<\/li>\n
              6. The two molecules 1,3 DPGA get dephosphorylated, to form two molecules of catalysed by DPGA kinase, here 2 ATP are formed.<\/li>\n
              7. The two molecules 1,3 PGA are rearranged to form two molecules of 2 PGA, catalysed by mutase.<\/li>\n
              8. The two molecules of 2PGA are enolated (dehydrated) to form, two molecules of phosphopyruvate, catalysed by enolase.<\/li>\n
              9. The two not of PEP are dephosphorylated to form two molecules of Pyruvate, and catalysed by PEP kinase. Here 2 ATPS are generated.<\/li>\n<\/ol>\n

                \"1st<\/p>\n

                2. Oxidative Decarboxylation:
                \nThis step is a connecting link between glycolysis, and Krebs cycle. Here pyruvic acid is decarboxylated to acetyl CoA, TPP, NAD, Mg+2<\/sup>, lipoic and the enzyme needed is pyruvate decarboxylase and dehydrogenase. NADH2<\/sub> is formed by the reduction of NAD.<\/p>\n

                3. Kreb\u2019s Cycle:
                \nAcetyl CoA produced in oxidative decarboxylation enters into the matrix of mitochondria and participates in Kreb\u2019s cycle.<\/p>\n

                1. The acetyl CoA combines with oxalo acetic to form citric acid in the presence of citrate synthetase. The first stable carbon compound is citric acid, hence it is also called as citric acid cycle.<\/p>\n

                2. Citric acid gets converted into Cis aconitic acid by losing a water molecule. It is then hydrated to form isocitric acid. These two reactions are brought about by aconitase enzyme.<\/p>\n

                3. Isocitric acid gets dehydrogenated to form oxalo succinic acid in the presence of dehydrogenase. The liberated hydrogen is accepted by NAD, and gets reduced NADH2<\/sub>.<\/p>\n

                4. Oxalosuccinic acid gets decarboxylated to a-keto glutaric acid in the presence of , decarboxylase enzyme. Here one CO2<\/sub> molecule is produced.<\/p>\n

                5. a-keto glutaric acid combines with coenzyme to form succinyl CoA in the presence of decarboxylase enzyme. During this, NAD is reduced to NADH2<\/sub> and a molecule CO2<\/sub> is also liberated.<\/p>\n

                6. Succinyl CoA loses CoA in the presence of succinyl thiokinase, to form succinic and during this conversion, a small amount of energy is liberated and is utilised for the formation of GTP.<\/p>\n

                7. Succinic acid gets dehydrogenated to form fiimaric acid in the presence of dehydrogenase.Here FAD gets reduced to FADH2<\/sub><\/p>\n

                8. Fumaric acid gets hydrated to form malic acid in the presence of fumerase enzyme.<\/p>\n

                \"1st<\/p>\n

                9. Malic acid is then dehydrogenated into oxaloacetic acid in the presence of dehydrogenase. Here NAD is reduced to NADH2 . <\/sub>This oxalo acetic acid again enters into Krebs cycle, and gets reused in the process.
                \nFor the complete oxidation of one glucose, Kreb\u2019s cycle takes place twice.<\/p>\n

                4. Electron Transport Chain\/ Terminal Oxidation \/ Phosphorylation:
                \nIt occurs on the inner mitochondrial membrane, using electron acceptor molecules. In this step the products of glycolysis and kreb\u2019s cycle i.e.. NADH2<\/sub>, and FADH2<\/sub> pass along the electron transport chain of mitochondria. The energy held by their hydrogen atoms is released, and utilised in the synthesis of ATPs. This includes two processes.<\/p>\n