Skip to main content

Understanding Respiration in Plants: A Complete Guide for Class 11 Biology Students with Types, Processes, and ATP Yield Explained


🌱 Respiration in Plants – Class 11 Biology (Chapter Summary)


Respiration is a crucial life process that allows plants to convert stored food into usable energy. Though plants make their own food through photosynthesis, they also need to break down that food to release energy, just like animals do.





📘 What is Respiration?


Respiration is the biochemical process in which the energy stored in glucose is released in the form of ATP (Adenosine Triphosphate). This occurs inside the cells and involves enzymatic breakdown of organic molecules.


🔄 Types of Respiration


1. Aerobic Respiration


Occurs in the presence of oxygen


End products: CO₂, H₂O, and energy


Most common in higher plants




2. Anaerobic Respiration (Fermentation)


Occurs in the absence of oxygen


End products: Ethanol and CO₂ (in yeast) or Lactic acid (in muscles)


Less energy is released compared to aerobic respiration


🔬 Glycolysis (Cytoplasm)


Glycolysis is the first step in both aerobic and anaerobic respiration.


Occurs in the cytoplasm


One glucose (6-carbon) molecule is broken into two molecules of pyruvate (3-carbon).


Energy produced: 2 ATP (net gain) and 2 NADH


🧬 Fate of Pyruvate


1. Aerobic Conditions (Mitochondria)


Pyruvate enters mitochondria


Undergoes oxidative decarboxylation


Forms Acetyl-CoA and enters the Krebs cycle



2. Anaerobic Conditions


Pyruvate is converted into:


Lactic acid (in some bacteria and muscle cells)


Ethanol and CO₂ (in yeast and some plant tissues


🔁 Krebs Cycle (Citric Acid Cycle)


Occurs in mitochondrial matrix


Acetyl-CoA combines with oxaloacetic acid to form citric acid


A series of reactions release:


3 NADH, 1 FADH₂, 1 ATP per Acetyl-CoA


CO₂ as a waste product


🔋 Electron Transport Chain (ETC)


Located on the inner mitochondrial membrane


NADH and FADH₂ donate electrons


Oxygen acts as the final electron acceptor


Water is formed, and ATP is synthesized (34 ATP molecules)


📊 Total ATP Yield from One Glucose Molecule:


Step ATP Produced


Glycolysis 2

Krebs Cycle 2

ETC 34

Total 38 ATP



(Note: Some books mention 36 ATP due to transport costs)


🌿 Special Features of Respiration in Plants


Plants have no specialized respiratory organs.


Gases are exchanged through stomata and lenticels.


No transport of O₂ or CO₂ via blood, unlike animals.


Respiration rate is lower in plants.


Stored carbohydrates like starch are broken down into glucose before respiration.


🔍 Differences between Photosynthesis and Respiration


Feature Photosynthesis Respiration


Energy Stored (ATP → glucose) Released (Glucose → ATP)

Occurs in Chloroplast Cytoplasm and Mitochondria

Gas exchange CO₂ in, O₂ out O₂ in, CO₂ out

Time Daylight only All the time


🌬️ Respiratory Quotient (RQ)


RQ = \frac{\text{Volume of CO}_2 \text{ evolved}}{\text{Volume of O}_2 \text{ consumed}}


RQ = 1 → Carbohydrate


RQ < 1 → Fats


RQ > 1 → Organic acids


🧠 Important Terms


ATP – Energy currency of the cell


Glycolysis – First step, glucose to pyruvate


Fermentation – Anaerobic breakdown of pyruvate


Krebs Cycle – Cyclic process in mitochondria


ETC – Final stage of aerobic respiration


📝 Final Summary


Respiration is essential for plant survival and energy production.


It occurs day and night, unlike photosynthesis.


All parts of a plant respire – roots, stems, and leaves.


Though simple, respiration is highly efficient, especially aerobic respiration.


📚 Practice Questions


1. What are the differences between aerobic and anaerobic respiration?



2. Explain the process of glycolysis with reactions.



3. Write

 the steps of Krebs cycle.



4. What is the role of mitochondria in respiration?



5. Why do plants have a low respiration rate?



"This Content Sponsored by Buymote Shopping app


BuyMote E-Shopping Application is One of the Online Shopping App


Now Available on Play Store & App Store (Buymote E-Shopping)


Click Below Link and Install Application: https://buymote.shop/links/0f5993744a9213079a6b53e8


Sponsor Content: #buymote #buymoteeshopping #buymoteonline #buymoteshopping #buymoteapplication"


Comments

Post a Comment

Popular posts from this blog

Understanding Amphibolic Pathways: Key to Energy Homeostasis and Cellular Metabolism in Health and Disease with Insights and Implications

 Amphibolic Pathway An amphibolic pathway is a metabolic pathway that plays a crucial role in energy production and utilization within cells. These pathways are unique in that they involve both catabolic and anabolic processes, allowing cells to efficiently manage energy resources. Key Characteristics 1. *Dual function*: Amphibolic pathways can be involved in both energy production (catabolism) and energy utilization (anabolism). This dual function allows cells to adapt to changing energy demands. 2. *Shared intermediates*: These pathways often share common intermediates between catabolic and anabolic processes. This sharing of intermediates enables cells to efficiently utilize energy resources. 3. *Regulation*: Amphibolic pathways are tightly regulated to ensure that energy production and utilization are balanced. This regulation is critical for maintaining energy homeostasis within cells. Examples 1. *Citric acid cycle (Krebs cycle)*: This pathway is a key example of an amphiboli...
Post a Comment
Read more

The Amazing Network: Everything You Need to Know About Body Fluids and Circulation (Class 11 Biology)

  Introduction: Why is "Body Fluids and Circulation" So Important?  * Start with a hook: Emphasize that every cell in our body needs a constant supply of nutrients and oxygen, and wastes must be removed. How does this happen?  * Introduce the concept of body fluids as the transporters.  * Briefly mention the two main body fluids (blood and lymph) and the circulatory system.  * State the objective of the blog post: to provide a detailed explanation of this crucial chapter for Class 11 Biology students. Section 1: The Life-Giving Fluid - Blood  * What is Blood?    * Define blood as a specialized connective tissue.    * Mention its composition: fluid matrix (plasma) and formed elements.  * Plasma: The Liquid Matrix (Around 55% of blood volume)    * Composition:      * Water (90-92%) - Emphasize its role in transport.      * Proteins (6-8%) - Explain the function of each:       ...
Post a Comment
Read more

"Detailed Explanation of Class 11 NCERT Biology Chapter: Biomolecules – Structure, Function, Types, and Role in Living Organisms"

Understanding Biomolecules – Class 11 Biology NCERT (Chapter 9) The Chemical Basis of Life Simplified Biomolecules are the building blocks of life. Everything that happens inside a cell — from energy production to genetic information transfer — involves biomolecules. In this blog, we break down Class 11 NCERT Chapter 9: Biomolecules into understandable chunks with real-life relevance and NCERT-aligned clarity. 🌱 1. What are Biomolecules? Biomolecules are organic compounds that are present in living organisms. These include: Carbohydrates (sugars) Proteins (chains of amino acids) Lipids (fats and oils) Nucleic acids (DNA and RNA) All these molecules play specific roles — some provide energy, others build structures, and some store genetic information. 🧪 2. How to Analyze Chemical Composition? To understand what makes up a living cell: Chemical analysis is performed on dried tissues. This helps separate: Micromolecules (molecular weight < 1000 Da): Water, minerals, salts, amino acid...
Post a Comment
Read more