NCERT Solutions for Class 11 Biology Chapter 12 Respiration in Plants

Download Respiration in Plants Class 11 Questions and Answers PDF

This chapter explains how plants break down food to release energy, a process known as respiration. Students can download the Respiration in Plants Class 11 Questions and Answers PDF for offline study.

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• NCERT Notes for Class 11 Biology Respiration in Plants
• NCERT Exemplar for Class 11 Biology Respiration in Plants

Get Class 11 Biology Chapter 12 Respiration in Plants Question Answer (Exercise Questions)

The questions with detailed explanations are given below. These are prepared by subject experts, following the latest NCERT curriculum to support learning. Regular practice of the Class 11 Biology Chapter 12 Respiration in Plants question answers helps in effective preparation.

Q1. Differentiate between (a) Respiration and Combustion

Answer:

Q1. Differentiate between (b) Glycolysis and the Krebs cycle

Answer:

Q1. Differentiate between (c) Aerobic respiration and Fermentation

Answer:

Q2. What are respiratory substrates? Name the most common respiratory substrate.

Answer: Respiratory substrates are those organic compounds that, during respiration, are oxidized for the release of energy within living cells. Examples of common respiratory substrates are carbohydrates, proteins, fats, and organic acids. The most frequent respiratory substrate is carbohydrates.

Q3. Give the schematic representation of glycolysis.

Answer: The flowchart of glycolysis is as follows:

Q4. What are the main steps in aerobic respiration? Where does it take place?

Answer: The key steps of aerobic respiration are as follows:

1. Glycolysis- Cytoplasm

2. Krebs cycle- Matrix of mitochondria

3. Electron transport system- Inner mitochondrial membrane

4. Oxidative phosphorylation- Oxysome in the inner mitochondrial membrane.

Q5. Give the schematic representation of an overall view of the Krebs cycle.

Answer: Schematic representation of the Krebs cycle

Q7. Distinguish between the following: (a) Aerobic respiration and Anaerobic respiration

Answer: The difference between aerobic respiration and anaerobic respiration is given below:

Q7. Distinguish between the following: (b) Glycolysis and Fermentation

Answer: The difference between Glycolysis and Fermentation is given below:

Q7. Distinguish between the following: (c) Glycolysis and the Citric Acid Cycle

Answer: The difference between Glycolysis and the Citric Acid Cycle is given below:

Q8. What are the assumptions made during the calculation of the net gain of ATP?

Answer: The assumptions used while calculating the net gain of ATP are as follows:

1. It is supposed that different steps of aerobic respiration, like glycolysis, the TCA cycle, and the ETS, follow one after the other in a regular pathway.

2. The NADH formed during glycolysis is transported into the mitochondria to undergo oxidative phosphorylation.

3. The glucose molecule is taken to be the sole substrate, and it is assumed that no other molecule goes into the pathway at intermediate stages.

4. The intermediates formed in respiration are not used for any other purpose.

Q9. Discuss "The respiratory pathway is an amphibolic pathway."

Answer: The respiratory pathway is amphibolic because it includes both the breakdown (catabolism) and the synthesis (anabolism) of molecules. Carbohydrates, fats, and proteins are broken into their simpler forms, such as glucose, fatty acids, glycerol, and amino acids, before respiration. Molecules of the respiratory pathway, such as acetyl-CoA, are also utilized for the synthesis of fatty acids and proteins.

Q10. Define RQ. What is its value for fats?

Answer:

The respiratory quotient (RQ) is defined as the ratio of the volume of CO₂ evolved to the volume of O₂ consumed during respiration. The value of the respiratory quotient depends on the type of respiratory substrate. The value of RQ for various respiratory substrates is as follows:

• Carbohydrates: 1

• Fats: 0.7

• Organic acids: slightly more than 1

• Proteins: approximately 0.8

Q11. What is oxidative phosphorylation?

Answer: Oxidative phosphorylation is the process of generating ATP through the use of energy released from respiration during the oxidation of NADH and FADH₂. The process is facilitated by the presence of the enzyme ATP synthase, which is a component of the electron transport system (ETS). In this process, oxidation-reduction reactions build up a proton gradient. There are two components of ATP synthase: F₀ and F₁. The F₀ component is located in the membrane and has a passage for protons, whereas the F₁ component is where ADP and inorganic phosphate are converted into ATP. One ATP molecule is produced for every two protons passing through the F₀-F₁ complex.

Q12. What is the significance of step-wise release of energy in respiration?

Answer: The respiration process occurs stepwise, involving steps such as glycolysis, the TCA cycle, ETS, and oxidative phosphorylation. The synthesis of ATP during respiration is also in every phase. The products obtained in one step of respiration serve as the substrate of the other pathway. Different molecules generated during respiration are also engaged in other biochemical processes. Various respiratory substrates enter and leave the pathway when needed. The ATP also gets used wherever needed, and the rate of reactions of enzymes is also regulated. Hence, step-by-step release of energy increases the efficiency of the system in extracting as well as storing energy.

NCERT Solutions for Class 11: Subject-wise

• NCERT Solutions for Class 11 Maths
• NCERT Solutions for Class 11 Chemistry
• NCERT Solutions for Class 11 Physics

Approach to Solve Respiration in Plants Class 11 Question Answer

Given below are a few steps that students can follow to answer the questions effectively.

• Students should begin by understanding the important processes. It includes glycolysis, the Krebs cycle, and the electron transport chain.

• They should focus on the difference between aerobic and anaerobic respiration and the role of ATP. Students can use the Class 11 Biology Chapter 12 Respiration in Plants question answer for clarity.

• The flowchart can be used to remember the sequence of reactions and their reagents.

• Solving the exemplar questions will give an advanced approach to the chapter. Regular revision of the Class 11 Biology Respiration in Plants question answer will improve understanding.

• The NCERT Solutions for Class 11 have all the solved exercise questions. All the answers are to the point and have the necessary information.

Check the NCERT Books and NCERT Syllabus here:

• NCERT Books Class 11 Biology

• NCERT Syllabus Class 11 Biology

• NCERT Books Class 11

• NCERT Syllabus Class 11

Important Questions of NCERT Class 11 Biology Chapter 12 Respiration in Plants

The solutions are designed to make learning easier for students. Below is an important question from this chapter. For more such questions, students can refer to the NCERT Solutions for Class 11 Biology Chapter 12 Respiration in Plants.

Q1. What is the end product of oxidative phosphorylation?

Options:

1. NADH

2. Oxygen

3. ADP

4. ATP + H₂O

Answer:

Oxidative phosphorylation occurs in mitochondria, using the electron transport chain to create a proton gradient that drives ATP synthesis; it releases chemical energy by oxidizing nutrients.

Hence, the correct answer is option (4) ATP + H₂O

Q2. The Electron Transport System (ETS) is located in the mitochondria

Options:

1. outer membrane

2. intermembrane space

3. inner membrane

4. matrix

Answer:

ETS is the electron transport system, which is a carrier molecule that can act as an electron acceptor as well as a donor, and it is present in the inner membrane of mitochondria. The electron transport chain is present in multiple copies in the inner mitochondrial membrane of eukaryotes and the plasma membrane of prokaryotes. It results in oxidative phosphorylation. The ETC is a series of proteins that receive the high-energy electrons from NADH and FADH2 and move them to the final acceptor, molecular oxygen.

Hence, the correct answer is option (3) inner membrane

Q3. Pyruvic acid, the key product of glycolysis, can have many metabolic fates. Under aerobic conditions, it forms

Options:

1. lactic acid

2. CO₂ + H₂O

3. acetyl CoA + CO₂

4. ethanol+ CO₂

Answer:

Acetyl CoA, CO_2, and NADH are the products obtained when Pyruvic acid undergoes a dehydrogenation reaction. An organic molecule with a backbone of three carbons, pyruvate is essential to an organism's processes of synthesis and degradation. It is used in bodybuilding supplements, the food business, and cancer screening, and when it is present in abnormal amounts, it is linked to a number of illnesses.

Hence, the correct answer is option (3) acetyl CoA + CO₂

Q4. Phosphorylation of glucose during glycolysis is catalyzed by

Options:

1. Phosphoglucomutase

2. Phosphoglucoisomerase

3. Hexokinase

4. Phosphorylase

Answer:

An enzyme called hexokinase catalyzes the initial stage of glycolysis, which converts glucose into energy for cellular metabolism.
Glucose is phosphorylated by this enzyme, which turns it into glucose-6-phosphate. ATP serves as both a phosphate donor and an energy source for hexokinase.

Hence, the correct answer is option (3) Hexokinase

Q5. Choose the correct statement:

Options:

1. Pyruvate is formed in the mitochondrial matrix.

2. During the conversion of succinyl-CoA to succinic acid, a molecule of ATP is synthesized.

3. Oxygen is vital in respiration for the removal of hydrogen.

4. There is a complete breakdown of glucose in fermentation.

Answer:

Oxygen drives the whole process of aerobic respiration and is responsible for driving out hydrogen, which is a vital process.

Hence, the correct answer is option (3). Oxygen is vital in respiration for the removal of hydrogen

What Students Learn from Respiration in Plants NCERT Solutions?

Respiration is the process through which living organisms release energy from food molecules. This chapter explains how plants break down glucose to obtain energy for various life activities.

1. Students understand the process of glycolysis, the Krebs cycle, and the electron transport system in detail.

2. The Respiration in Plants Class 11 question answer helps them to differentiate between aerobic and anaerobic respiration.

3. They learn how energy is stored and released in the form of ATP molecules.

4. Students explore the role of mitochondria and enzymes in cellular respiration through the Class 11 Biology Respiration in Plants question answer.

5. They also study how the respiratory quotient (RQ) varies with different respiratory substrates.

Why Class 11 Biology Chapter 12 Respiration in Plants NCERT Solutions are Important?

The Respiration in Plants chapter explains how plants release energy by breaking down the food molecules. Students will understand the types of respiration, such as aerobic and anaerobic respiration, glycolysis, the Krebs cycle, and the electron transport chain.

• Class 11 Biology Chapter 12 Respiration in Plants NCERT Solutions are important as they describe the role of mitochondria and enzymes in the process of respiration.
• Students will understand the difference between aerobic and anaerobic respiration, along with examples, by using the solutions.
• Different types of cycles, such as the Krebs cycle, electron transport chain, and glycolysis, are included in the solutions, along with flow charts.
• Step-by-step solutions help students to know the flow of electrons, ATP synthesis, and other respiratory pathways, which are frequently asked in competitive exams like NEET.

What Extra Should Students Study Beyond the NCERT for NEET?

Studying concepts beyond the NCERT will help in improving knowledge for competitive exams like NEET. Some extra concepts that can be studied are given below in the table. Along with these concepts, students should practice the diagrams given in the NCERT Solutions for Class 11 Biology Chapter 12 Respiration in Plants.

Chapter-wise NCERT Solutions for Class 11 Biology

Below are the chapter-wise solutions that help students understand the important topics easily and perform well in the competitive exams.