Respiration in Plant MCQ Quiz - Objective Question with Answer for Respiration in Plant - Download Free PDF

Concept-

• An important feature of all living cells is respiration which is related to the liberation of metabolic energy as ATP.
• Respiration is an amphibolic and exergonic cellular process.
• Respiration is of two types.
  • Aerobic respiration- with the use of oxygen. Eg plants
  • The equation of Aerobic Respiration
    • Glucose + Oxygen → Carbon dioxide + Water + Energy
  • Anaerobic respiration- without the use of oxygen. Eg yeast
  • The equation of Anaerobic Respiration
    • Glucose → Alcohol + Carbon dioxide + Energy

Explanation:

• 2 molecules of ATP are obtained by the anaerobic respiration of one molecule of glucose.
• Respiration is a glucose degradation mechanism with the aid of molecular oxygen to generate ATP.
• It requires both glycolysis and phosphorylation.
• Glycolysis is the first step of glucose degradation that occurs in the absence of oxygen and transforms one glucose molecule into two pyruvate molecules.
• During this cycle, 4 ATP molecules are generated and 2 ATP molecules are consumed.

So, in anaerobic respiration Alcohol, Carbon dioxide, Energy obtained.

The correct answer is Glucose → Pyruvic acid → CO₂ + Water.

Key Points

• Aerobic respiration involves the complete breakdown of glucose in the presence of oxygen.
• The pathway of glucose breakdown starts with glycolysis, where glucose is converted into pyruvic acid.
• In the presence of oxygen, pyruvic acid enters the mitochondria and undergoes further breakdown to form CO₂ and water, releasing energy in the process.
• This energy is used to produce ATP, the main energy currency of cells, through the electron transport chain and oxidative phosphorylation.

Additional Information

• Aerobic Respiration:
  • Aerobic respiration is a type of cellular respiration that occurs in the presence of oxygen.
  • It consists of three main stages: Glycolysis, the Citric Acid Cycle (Krebs Cycle), and the Electron Transport Chain (ETC).
• Glycolysis:
  • Glycolysis is the first step in glucose metabolism and occurs in the cytoplasm of the cell.
  • It breaks down one molecule of glucose (6-carbon) into two molecules of pyruvate (3-carbon), producing 2 ATP and 2 NADH molecules.
• Citric Acid Cycle (Krebs Cycle):
  • Pyruvic acid produced from glycolysis is converted into acetyl-CoA, which enters the citric acid cycle.
  • Through a series of reactions, CO₂ is released, and electrons are transferred to NADH and FADH2.
• Electron Transport Chain:
  • The final stage of aerobic respiration takes place in the mitochondria, where electrons from NADH and FADH2 are transferred through protein complexes.
  • This creates a proton gradient that drives the synthesis of ATP and the reduction of oxygen to form water.

The correct answer is Carbon dioxide.

Key Points

• Stomata are tiny pores on the surface of leaves through which plants take in carbon dioxide and releases oxygen.
• On the underside of the leaf, the stomata are present.
• The singular word for stomata is a stoma.
• In order to reduce water loss plants in deserts have only a few stomata and the Guard cells which are present in stoma are kidney-shaped.
• The Guard cells which are present in stomata perform the function of producing sugars, regulating the amount of water lost and chloroplast storage.
• The process by which the wetness and other gaseous wastes are removed through the stomata of the leaf, lenticels of the stem, and fruits is called transpiration.
• During the day, when the stomata are open, the transpiration pull becomes the important driving force in the motion of water in the xylem.
• During the night the stomata can close and transpiration can be stopped.
• The water is transformed into the stem and leaf by the cohesion of water molecules to one another as well as the adhesion of water to the cell walls of the xylem vessels and tracheids in the plant.

Image showing stomata:

Concept-

• An important feature of all living cells is respiration which is related to the liberation of metabolic energy as ATP.
• Respiration is an amphibolic and exergonic cellular process.
• Respiration is of two types-
  • Aerobic respiration- with the use of oxygen. Eg plants
  • Anaerobic respiration- without the use of oxygen. Eg yeast

Explanation-

• The respiratory Quotient is defined as the ratio of the volume of CO₂ liberated for the volume of O₂ consumed.
• RQ = CO₂ eliminated / O2 consumed.
• The value of R.Q.  depends upon the type of respiratory substance utilized & measured by the device Ganong’s respirometer.

Thereby R.Q. stands for nature of respiratory.

Additional Information

• When fats are used in respiration, the RQ is less than 1.
• Calculations for a fatty acid, tripalmitin-​

2(C51H98O6) + 145O2 102CO2 + 98H2O + energy

RQ = 102CO2/145O2 = 0.7

• The R.Q. of Carbohydrates is 1

C₆H₁₂O₆  + 6O₂ +6H₂O   6CO₂ + 12H₂O + E

• The R.Q. of proteins is 0.8 or 0.9 or < 1.

The correct answer is Glucose.

Key Points

• Glucose is the primary molecule that is metabolized in the cells to produce energy.
• During cellular respiration, glucose combines with oxygen to produce carbon dioxide, water, and energy (ATP).
• This process occurs in the mitochondria of the cell and is known as aerobic respiration.
• Glucose metabolism is essential for providing the energy required for various cellular activities.

Additional Information

• Cellular Respiration:
  • It is the process by which cells convert glucose and oxygen into energy, carbon dioxide, and water.
  • It consists of three main stages: Glycolysis, the Citric Acid Cycle (Krebs Cycle), and the Electron Transport Chain.
• Aerobic vs. Anaerobic Respiration:
  • Aerobic respiration requires oxygen and produces more ATP compared to anaerobic respiration.
  • Anaerobic respiration occurs in the absence of oxygen and results in the production of lactic acid or ethanol and less ATP.
• ATP (Adenosine Triphosphate):
  • ATP is the primary energy carrier in cells.
  • It is produced during cellular respiration and used for various cellular processes.
• Mitochondria:
  • Known as the powerhouse of the cell, mitochondria are responsible for producing ATP through cellular respiration.
  • They have their own DNA and are involved in other processes such as signaling, cellular differentiation, and cell death.

Concept:

• The breaking of the C-C bonds of complex compounds through oxidation within the cells, leading to the release of a considerable amount of energy is called respiration.
• The compounds that are oxidized during this process are known as respiratory substrates.
• ATP acts as the energy currency of the cell.
• This energy trapped in ATP is utilized in various energy-requiring processes of the organisms. 
• There are two types of respiration
  • Aerobic Respiration- In the Presence of oxygen.
  • Anaerobic respiration- In absence of oxygen.
  • C6H12O6 → 2C2H5O H + 2CO2 + Energy 

Explanation:

Fermentation:

• This process does not require oxygen.
•  Alcohol or wine is formed by the use of fermentation.
• It is also used in the manufacture of yogurt, vinegar, and other chemical substances. 
• The process of fermentation occurs in the presence of micro-organisms.
• The fermentation of lactose produces lactic acid.
• Which reacts with milk protein and converts it into curd.

Important Points

Respiration is of 2 types:

Thus, anaerobic respiration is also called fermentation.

The correct answer is Stomata.

Key Points

• Stomata
  • In leaves transpiration takes place through stomata.
  • The little apertures known as stomata are found on the epidermis of leaves.
  • Stomata are visible under a light microscope.
  • Stomata can be found on the stems and other portions of various plants.
  • In gaseous exchange and photosynthesis, stomata are crucial. Via opening and closing, they regulate the rate of transpiration.

Additional Information

• Transpiration
  • Water is lost from the aerial regions of plants in the form of water vapour through a biological process called transpiration.
  • Like all other living things, plants need an excretory system to remove extra water from their bodies.
  • Transpiration is the term for this process of removing extra water from the body of the plant. Typically, it is the evaporation of water from the leaf surface.
  • The plants only use a small portion of the water they absorb for growth and development. 

The correct answer is, 'Transpiration'.Key Points

• Transpiration is a process that involves loss of water vapour through the stomata of plants.
  • Transpiration plays a major role in the process of photosynthesis.
    • Water is essential for a plant's growth and survival, but only 0.5-3% is used by its roots for growth and metabolism.
    • The rest of the water exits through the transpiration process from the stomata in plants.
    • More leaves mean bigger stomata. The transpiration rate is higher in such plants.

Additional Information

• Plant saturation is the limit at which the light no longer increases the rate of photosynthesis.
  • Light is used to increase the rate of photosynthesis in plants.
• Herbigation is a process of applying herbicides with the help of an irrigation system.
  • It is a method used to control undesired plants. 
• Evaporation is the process in which liquid turns into vapor.
  • Evaporation also plays a major role in the process of photosynthesis.

The correct answer is Zero.

Key Points

• The term glycolysis has originated from the Greek words, glycos for ''sugar'' and lysis for ''splitting''.
• The scheme of glycolysis was given by Gustav Embden, Otto Meyerhof, and J. Parnas, and is often referred to as the EMP pathway.
• In anaerobic organisms, it is the only process in respiration.
• Glycolysis occurs in the cytoplasm of the cell and is present in all living organisms.
• In this process, glucose undergoes partial oxidation to form two molecules of pyruvic acid.

​Explanation:

• The glycolysis is a common pathway for aerobic and anaerobic respiration and no oxygen O₂ is consumed during this process.
• It is a universal pathway that occurs in every living organism be it be aerobic or anaerobic.
• Therefore, the number of oxygen molecules required during glycolysis of one glucose molecule is ''Zero''

Additional Information 

• It involves a series of 10 biochemical reactions where 1 molecule of glucose is degraded to 2 molecules of pyruvic acid.
• Each step is governed by some enzyme.
• In plants, this glucose is derived from sucrose, which is the end product of photosynthesis, or from storage carbohydrates.
• Sucrose is converted into glucose and fructose by the enzyme, invertase, and these two monosaccharides readily enter the glycolytic pathway.
• Glucose and fructose are phosphorylated to give rise to glucose-6- phosphate by the activity of the enzyme hexokinase.
• This phosphorylated form of glucose then isomerizes to produce fructose-6- phosphate.
• Subsequent steps of the metabolism of glucose and fructose are the same.
• In glycolysis, a chain of ten reactions, under the control of different enzymes, takes place to produce pyruvate from glucose

The correct answer is Thallophyta.

• Litmus solution is a purple dye, extracted from lichens, a plant belonging to the Thallophyta division, and is commonly used as an indicator.
  • When litmus solution is neither acidic nor alkaline, its color is purple.
  • The main use of litmus is to test whether a solution is acidic or alkaline, as blue litmus paper turns red under acidic conditions, and red litmus paper turns blue under alkaline or alkaline conditions.
  • Neutral litmus paper is purple.

Additional Information

• Classification of Kingdom Plantae
  • The plant kingdom is classified into five subgroups according:
    • Thallophyta: Thallophyta includes plants with primitive and simple body structure.
      • The plant body is a thallus, they can be filamentous, colonial, branched or unbranched.
      • Examples include green algae, red algae and brown algae.
      • Common examples are Volvox, Fucus, Spirogyra, Chara, Polysiphonia, Ulothrix etc.
    • Bryophyta: Bryophytes do not have vascular tissue.
      • The plant body consists of root-like, stem-like and leaf-like structures.
      • Bryophytes are terrestrial plants but are known as "amphibians of the plant kingdom" because they require water for sexual reproduction.
      • They are present in moist and shady places. Bryophyta includes mosses, hornworts and liverworts.
      • Some common examples are Marchantia, Funaria, Sphagnum, Anthoceros etc.
    • Pteridophyta: Pteridophytes consist of a well differentiated plant body in root, stem and leaves.
      • They have a vascular system for conducting water and other substances.
      • Some common examples are Selaginella, Equisetum, Pertis etc.
    • Gymnosperms: Gymnosperms have a well differentiated plant body and vascular tissue.
      • They bear naked seeds, i.e. the seeds are not enclosed within a fruit.
      • Some common examples of gymnosperms are Cycas, Pinus, Ephedra, etc.
    • Angiosperms: Angiosperms are seed-bearing vascular plants with a well-differentiated plant body.
      • The seeds of angiosperms are enclosed within the fruits.

The correct answer is Tissue respiration.

Key Points

Explanation:

• The breaking of the C-C bonds of complex compounds through oxidation within the cells, leading to the release of a considerable amount of energy is called respiration. 
• The compounds that are oxidized during this process are known as respiratory substrates. Usually, carbohydrates are oxidized to release energy, but proteins, fats, and even organic acids can be used as respiratory substances in some plants, under certain conditions.
• Along with the energy carbon dioxide and metabolic water is also released as a by-product in respiration.
• For example The complete combustion or oxidation of 1 mol. glucose produces 6CO₂  and 6H₂O (metabolic water) as end products

• Thus, the correct option is ''Tissue respiration''

​Additional Information

• Digestion: The process of conversion of complex food substances to simple absorbable forms is called digestion and is carried out by our digestive system by mechanical and biochemical methods
• Excretion is the process of removal of nitrogenous waste material from the body. Excretion is performed by a specialized group of cells or organs called excretory organs.
• Muscle is a specialized tissue of mesodermal origin. They have special properties like excitability, contractility, extensibility, and elasticity

The correct answer is 1 i.e. Cytoplasm.

Key Points

Glycolysis:

• The term glycolysis has originated from the Greek words, glycos for sugar, and lysis for splitting.
• The scheme of glycolysis was given by Gustav Embden, Otto Meyerhof, and J. Parnas, and is often referred to as the EMP pathway.
• In anaerobic organisms, it is the only process in respiration.
• Glycolysis occurs in the cytoplasm of the cell and is present in all living organisms.
• In this process, glucose undergoes partial oxidation to form two molecules of pyruvic acid.
• In plants, this glucose is derived from sucrose, which is the end product of photosynthesis, or from storage carbohydrates.
• Sucrose is converted into glucose and fructose by the enzyme, invertase, and these two monosaccharides readily enter the glycolytic pathway.
• Glucose and fructose are phosphorylated to give rise to glucose-6- phosphate by the activity of the enzyme hexokinase.
• This phosphorylated form of glucose then isomerizes to produce fructose-6- phosphate.
• Subsequent steps of metabolism of glucose and fructose are the same.
• In glycolysis, a chain of ten reactions, under the control of different enzymes, takes place to produce pyruvate from glucose.

The correct answer is Aquatic submerged plants.

Concept:

• Transpiration is the phenomenon of the loss of water in the form of vapor from the living tissues of aerial parts of the plant. 
• Water lost is pure water solutes.
• The process of transpiration is carried out by the special structures found in the leaves of plants called stomata. It occurs mainly through stomata.
• It is both a physical and physiological process.

Explanation:

• Aquatic submerged plants do not show transpiration because they do not require a stoma pore for gaseous exchange, they lack stomata on the leaf surface. 
• Instead, the gaseous exchange can be accomplished through diffusion through the leaf surface. 
• As a result, submerged aquatic plants lack a cuticle structure.
• The cuticle's main function is to prevent excess water through transpiration, and since there are no stomata or transpiration, the cuticle layer is also absent.

Additional Information

Transpiration is of 3 types:

• Stomatal transpiration: Occurs through stomata, about 80-90% of transpiration occurs by stomata.
• Cuticular transpiration: loss of water through the cuticle of herbaceous stems and leaves. The cuticle is the waxy layer present on the epidermis. About 9% of transpiration occurs through it.
• Lenticular transpiration: Occurs through lenticels(minute pores on stem and epidermis of woody plants). The least amount of about 0.1 to 1% transpiration occurs through it.

Important Points 

• Minimum transpiration is found in succulent xerophytes.
• Maximum transpiration occurs in mesophytes.

The correct answer is Fermentation.

Key Points

• Fermentation is a chemical process by which molecules such as glucose are broken down anaerobically.
• There are three different types of fermentation.

Lactic Acid Fermentation

• Starch or sugar is converted into lactic acid by yeast strains and bacteria.
• During exercise, the occurrence of muscle cramps is due to lactic acid formation.
• The energy expenditure is faster than the oxygen supplied to the muscle cells.

Alcohol Fermentation

• Alcoholic fermentation is the process by which ethanol and carbon dioxide are produced from sugars like fructose, glucose, and sucrose by yeasts during their production of cellular energy.

Acetic Acid Fermentation

• ​Vinegar is obtained from the fermentation of ethanol by acetic acid bacteria.

The correct answer is "Phloem".

Key Points:

Facts About Phloem:

• ​It is a Plant vascular tissue.
• It conducts foods made in the leaves during photosynthesis to all other parts of the plant.
• Phloem is found in:
  • ​The external part of root cylinders.
  • In the stem vascular bundles.
  • In the abaxial part of the venations of every single leaf.
• Composed of 3 cell types:
  • ​Sieve tubes: 
    • ​Elongated living cells.
    • Conveys carbohydrates, chiefly sucrose from leaves to roots and fruits.
  • Phloem fibers:
    • ​It is commercially useful.
    • Possess great pliability and tensile strength.
  • Phloem parenchyma:
    • Also known as transfer cells.

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Additional Information: