NCERT Solutions For Class 11 Biology Chapter 20 Locomotion And Movement in Hindi - 2025-26
FAQs on NCERT Solutions For Class 11 Biology Chapter 20 Locomotion And Movement in Hindi - 2025-26
1. Where can I find accurate and step-by-step NCERT Solutions for Class 11 Biology Chapter 20, Locomotion and Movement?
You can access reliable and detailed NCERT Solutions for Class 11 Biology Chapter 20, prepared by subject matter experts. These solutions provide a step-by-step guide to all the textbook questions, ensuring complete alignment with the CBSE 2025-26 syllabus and the official marking scheme.
2. How should I answer the question on drawing the structure of a sarcomere from the NCERT textbook?
To answer this question correctly and score full marks, you should follow these steps as demonstrated in the NCERT solutions:
Draw two parallel Z-lines which form the boundaries of the sarcomere.
Illustrate the thin actin filaments attached to each Z-line and extending towards the centre.
Draw the thick myosin filaments in the central part, showing their overlap with the actin filaments.
Clearly label the key regions: the A-band (length of the myosin filament), I-band (region with only actin filaments), and the H-zone (central region with only myosin filaments).
3. Why is the sliding filament theory a complex topic, and how do the NCERT solutions help simplify it?
The sliding filament theory is considered complex because it involves a precise sequence of molecular events, including the roles of proteins like actin, myosin, troponin, and the function of ATP and calcium ions. The NCERT solutions simplify this by breaking the process down into logical, sequential steps:
The initial signal from the nervous system.
The release of calcium ions and their binding to troponin.
The formation of the cross-bridge between actin and myosin.
The 'power stroke' or sliding mechanism powered by ATP hydrolysis.
This step-wise explanation helps students understand the cause-and-effect relationships within muscle contraction, which is essential for writing a complete answer.
4. What key points must be included when answering questions about the differences between red and white muscle fibres as per the NCERT exercise?
When differentiating between red and white muscle fibres, the NCERT solutions guide you to structure your answer based on these key comparative points:
Myoglobin Content: High in red fibres (making them appear red), but low in white fibres.
Mitochondria: Red fibres have numerous mitochondria for aerobic respiration, while white fibres have few.
Sarcoplasmic Reticulum: The amount is low in red fibres but high in white fibres.
Mode of Respiration: Red fibres are aerobic, whereas white fibres primarily depend on anaerobic respiration.
Rate of Contraction: Red fibres contract slowly for a longer duration, while white fibres contract fast for shorter durations.
5. How do the NCERT Solutions for Chapter 20 go beyond just providing answers and help in building a strong conceptual foundation?
The NCERT Solutions for this chapter build a strong foundation by explaining the 'why' behind each answer, not just the 'what'. For example, when solving a question on joints, the solutions don't just name the type but also explain its functional significance—like why a ball-and-socket joint in the shoulder allows for multi-axial movement. This approach helps students connect anatomical structures to their physiological roles, which is vital for tackling higher-order thinking questions in exams.
6. How can I correctly solve the NCERT questions related to disorders of the muscular and skeletal system?
To correctly solve questions on disorders like Myasthenia gravis, Tetany, or Arthritis, you should focus on three aspects for each disorder as per the CBSE pattern:
Cause: Briefly explain the underlying reason (e.g., autoimmune issue at the neuromuscular junction, low Ca++ in body fluid, or inflammation of joints).
Key Symptom: Mention the primary characteristic (e.g., fatigue and paralysis of skeletal muscles, rapid spasms, or joint pain).
System Affected: Clearly state if it is a muscular or skeletal disorder.
The NCERT solutions model this structured approach to help you write clear and high-scoring answers.
7. Why is it important to use precise terminology from the NCERT textbook when writing answers, and how do the solutions reinforce this?
Using precise terminology such as sarcomere, Z-line, cross-bridge, and neuromuscular junction is critical because biology is a science of specifics, and vague language can lead to a loss of marks. The NCERT solutions consistently use the correct scientific terms in every explanation and step-by-step answer. This reinforces the correct vocabulary and trains you to write answers that are not only conceptually correct but also technically accurate, meeting the high standards of CBSE examiners.
8. What is the correct method for describing the three types of joints as per the NCERT solutions?
The NCERT solutions explain that joints should be classified based on their degree of mobility. The correct method to describe them is:
Fibrous Joints: Described as immovable joints, such as the sutures in the skull, held together by dense fibrous connective tissues.
Cartilaginous Joints: Explained as joints allowing limited movement, where bones are joined by cartilage, like the joints between adjacent vertebrae.
Synovial Joints: Characterised as freely movable joints containing a synovial fluid-filled cavity. The solutions then detail specific types like ball and socket, hinge, pivot, and saddle joints with examples.

















