RBSE Class 11th 2026 HALF-YEARLY-BIOLOGY-1127-011225 Previous Year Papers

कक्षा 11वीं अर्द्ध वार्षिक परीक्षा, 2025-26
जीव विज्ञान / BIOLOGY

समय : 3.45 घंटे  |  पूर्णांक : 80

सामान्य अनुदेश / General Instructions:

1. परीक्षार्थी प्रश्न-पत्र के पहले पृष्ठ पर अपना अनुक्रमांक अवश्य लिखें। / Candidate must write his/her Roll Number on the first page of the Question Paper.
2. प्रत्येक प्रश्न के सामने उसका अंक भार अंकित है। / Marks for every question are indicated alongside.

SECTION - A / खण्ड - अ

वस्तुनिष्ठ प्रश्न / Objective Type Questions

प्रश्न 3.40

प्रोटीन क्रियाधार का श्वसन गुणांक होता है -

• (A) 4
• (B) 0.9
• (C) 0.7
• (D) 0.5

सही उत्तर: (B) 0.9
प्रोटीन के श्वसन में ऑक्सीजन की खपत और कार्बन डाइऑक्साइड उत्सर्जन का अनुपात लगभग 0.9 होता है।

प्रश्न 3.41

धूम्रपान के कारण होने वाला श्वसनी विकार है -

• (A) दमा (Asthma)
• (B) श्वसनीशोथ (Bronchitis)
• (C) न्यूमोनिया (Pneumonia)
• (D) वातस्फीति (Emphysema)

सही उत्तर: (B) श्वसनीशोथ (Bronchitis)
धूम्रपान से श्वसनी में सूजन आ जाती है, जिसे ब्रोंकाइटिस कहते हैं।

रिक्त स्थानों की पूर्ति कीजिए -

1. चमगादड़, चूहा और मानव स्तनधारी वर्ग में आते हैं।
2. प्रोकैरियोटिक कोशिका के वृत्ताकार जीनोमिक DNA को न्यूक्लियॉइड कहते हैं।
3. लेग्यूमिनोसी कुल में पुष्पदलविन्यास पाया जाता है।

अति लघु उत्तरीय प्रश्न -

प्रश्न 1: अनिषेक फल को परिभाषित कीजिए।

प्रश्न 2: अबीज बीज के कोई दो उदाहरण दीजिए।

प्रश्न 3: त्वचारोम क्या होते हैं?

प्रश्न 4: भारतीय मेंढक का वैज्ञानिक नाम क्या है?

प्रश्न 5: समसूत्री विभाजन का एक महत्व लिखिए।

प्रश्न 6: श्वसनी पथ को एम्फीबोलिक पथ क्यों कहते हैं?

प्रश्न 7: आर्थ्रोपोडा व एनेलिडा संघ में पाए जाने वाले श्वसन अंगों के नाम लिखिए।

प्रश्न 8: द्विकला से घिरे दो कोशिकांगों के नाम लिखिए।

लघु उत्तरात्मक प्रश्न – Short Answer Type Questions

1. जीवाणुभोजी का नामांकित चित्र बनाइए।
   Draw a labelled diagram of Bacteriophage.

   Solution: A bacteriophage (or phage) is a virus that infects bacteria. Its structure consists of:

   • Head (Capsid): Icosahedral structure containing genetic material (DNA or RNA).
   • Collar: Connects head to tail.
   • Tail (Sheath): Hollow tube through which genetic material is injected.
   • Base plate: At the end of tail, helps in attachment.
   • Tail fibers: Help in recognizing and binding to bacterial cell surface.

   (Note: A labelled diagram should show these parts clearly.)

2. मोनेरा जगत के विशिष्ट चारित्रिक लक्षण लिखिए।
   Write down the peculiar characteristic features of Kingdom Monera.

   Solution: Peculiar characteristics of Kingdom Monera:

   • Prokaryotic organisms (no true nucleus or membrane-bound organelles).
   • Unicellular, though some form colonies.
   • Cell wall present (made of peptidoglycan in bacteria).
   • Reproduce asexually by binary fission, budding, or fragmentation.
   • Nutrition: autotrophic (photosynthetic/chemosynthetic) or heterotrophic (saprophytic/parasitic).
   • Genetic material is a single circular DNA molecule (nucleoid).
   • Examples: Bacteria, Cyanobacteria (blue-green algae), Archaebacteria.

3. लिवरवर्ट और मॉस में अंतर लिखिए।
   Differentiate between Liverwort and Moss.

   Character	Liverwort	Moss
   Plant body	Thalloid, dorsiventral, without differentiation into stem and leaves	Erect, with stem-like and leaf-like structures
   Rhizoids	Unicellular	Multicellular
   Sporophyte	Simple, without seta, capsule dehisces by valves	Differentiated into foot, seta, and capsule; capsule opens by operculum
   Examples	Marchantia, Riccia	Funaria, Polytrichum

4. निम्नलिखित को सुमेलित कीजिए –
   Match the following –

   (i) वॉलवॉक्स (Volvox) – (a) टेरिडोफाइट (Pteridophyte)
   (ii) सेलाजिनेला (Selaginella) – (b) जिम्नोस्पर्म (Gymnosperm)
   (iii) सीड्रस (Cedrus) – (c) शैवाल (Algae)

   Correct Matching:

   • (i) Volvox – (c) Algae (शैवाल)
   • (ii) Selaginella – (a) Pteridophyte (टेरिडोफाइट)
   • (iii) Cedrus – (b) Gymnosperm (जिम्नोस्पर्म)

5. “सभी कशेरुकी रज्जुकी हैं लेकिन सभी रज्जुकी कशेरुकी नहीं हैं।” इस कथन को सिद्ध कीजिए।
   “All vertebrates are chordates but all chordates are not vertebrates.” Justify the statement.

   Solution: Chordates are animals possessing a notochord, dorsal hollow nerve cord, pharyngeal slits, and a post-anal tail at some stage. Vertebrates are a subphylum of chordates where the notochord is replaced by a vertebral column (backbone).

   • All vertebrates are chordates because they possess all four chordate characteristics at some stage of life (e.g., in embryos, the notochord is present before being replaced by vertebrae).
   • Not all chordates are vertebrates because there are chordates like Urochordates (e.g., Ascidia) and Cephalochordates (e.g., Amphioxus) that never develop a vertebral column; they retain the notochord throughout life.

   Thus, vertebrates are a subset of chordates.

6. परजीवी प्लैटिहेल्मिन्थीज के विशिष्ट लक्षण लिखिए।
   Write peculiar features of parasitic platyhelminthes.

   Solution: Peculiar features of parasitic platyhelminthes (e.g., tapeworms, flukes):

   • Body is dorsoventrally flattened, leaf-like or ribbon-like.
   • Absence of digestive system in some (e.g., tapeworms absorb nutrients directly through body surface).
   • Presence of suckers and hooks for attachment to host.
   • Hermaphroditic (both male and female reproductive organs in same individual).
   • High reproductive capacity (produce many eggs).
   • Reduced nervous and sensory systems.
   • Protective covering (tegument) resistant to host digestive enzymes.

7. C₃ और C₄ पौधों में तीन अंतर लिखिए।
   Write three differences between C₃ and C₄ plants.

   Character	C₃ Plants	C₄ Plants
   First stable product	3-phosphoglyceric acid (3-PGA) – a 3-carbon compound	Oxaloacetic acid (OAA) – a 4-carbon compound
   Leaf anatomy	No bundle sheath cells; mesophyll cells perform Calvin cycle	Kranz anatomy: bundle sheath cells surround vascular bundles; Calvin cycle occurs in bundle sheath
   Photorespiration	High photorespiration (loss of CO₂)	Very low or absent photorespiration

8. परिवर्धन और प्लास्टिसिटी को परिभाषित कीजिए।
   Define development and plasticity.

   Solution:

   • Development: The sum total of all changes that an organism undergoes from the time of fertilization (or germination) until death. It includes growth, differentiation, and maturation.
   • Plasticity: The ability of an organism to alter its development (morphology, physiology, or behavior) in response to environmental conditions. For example, in plants, the same genotype can produce different phenotypes under different environments (e.g., heterophylly in aquatic plants).

9. टिप्पणी लिखिए – अंकगणितीय वृद्धि
   Write short note on – Arithmetic growth

   Solution: Arithmetic growth is a type of growth in which the increase in size or number occurs at a constant rate over time. In this pattern, only one daughter cell continues to divide while the other differentiates and matures. The mathematical expression is: L_t = L₀ + rt, where L_t is length at time t, L₀ is initial length, and r is the constant rate of growth. Example: Growth of root or shoot apex in length (elongation). The graph of arithmetic growth is a straight line.

10. प्रकाशीय श्वसन क्या है? उन कोशिकांगों के नाम लिखिए जिनमें प्रकाशीय श्वसन होता है।
    What is Photorespiration? Name the organelles in which photorespiration occurs.

    Solution: Photorespiration is a process in plants where, in the presence of light, the enzyme RuBisCO fixes oxygen instead of carbon dioxide, leading to a wasteful pathway that releases CO₂ without producing ATP or NADPH. It occurs in C₃ plants when CO₂ concentration is low and O₂ concentration is high.

    Organelles involved in photorespiration:

    1. Chloroplasts – where RuBisCO catalyzes the oxygenation of RuBP.
    2. Peroxisomes – where glycolate is converted to glycine and then serine.
    3. Mitochondria – where glycine is converted to serine with release of CO₂.

दीर्घ उत्तरात्मक प्रश्न

Long Answer Type Questions

निबंधात्मक प्रश्न

Essay Type Questions