CBSE Class 11 Biology Very Short Answer Questions – Morphology of Flowering Plants (Chapter 5) | NCERT-Based

Course & Examination Details

Course: CBSE Class 11 Biology
Unit: Unit II – Structural Organisation in Animals and Plants
Chapter: Chapter 5 – Morphology of Flowering Plants
Prescribed By: CBSE Board (NCERT Syllabus)
Question Type: Very Short Answer Questions (VSA)

Section I: Root (Questions 1–10)

Q1. What is a root?

Answer: Root is the underground part of the plant axis arising from the radicle, mainly responsible for absorption, anchorage, storage, and synthesis of plant growth regulators.

Q2. What is a tap root system?

Answer: Tap root system develops from the radicle and consists of a main primary root with lateral branches, commonly found in dicotyledonous plants.

Q3. Define fibrous root system.

Answer: Fibrous root system consists of numerous thin roots arising from the base of the stem, replacing the radicle, and is characteristic of monocotyledonous plants.

Q4. What are adventitious roots?

Answer: Adventitious roots arise from parts other than the radicle, such as stem or leaves, and help in support, storage, respiration, or vegetative propagation.

Q5. What are storage roots?

Answer: Storage roots are modified roots that store reserve food materials, enabling plants to survive unfavourable conditions, as seen in carrot, radish, and sweet potato.

Q6. What are prop roots?

Answer: Prop roots are adventitious roots arising from branches, growing vertically into the soil to provide additional mechanical support, commonly seen in banyan trees.

Q7. What are stilt roots?

Answer: Stilt roots arise from the lower nodes of the stem, grow obliquely into the soil, and provide mechanical support to plants like maize and sugarcane.

Q8. What are pneumatophores?

Answer: Pneumatophores are specialized respiratory roots found in mangrove plants that grow vertically upward to facilitate gaseous exchange in waterlogged soils.

Q9. Name the root modification seen in parasitic plants.

Answer: Haustorial roots are found in parasitic plants like Cuscuta and help absorb nutrients and water from the host plant tissues.

Q10. Which root modification helps in respiration?

Answer: Pneumatophores help in respiration by allowing gaseous exchange through lenticels in plants growing in marshy or waterlogged environments.

Section II: Stem (Questions 11–20)

Q11. Define stem.

Answer: Stem is the ascending aerial part of the plant axis that bears branches, leaves, flowers, and fruits, and conducts water, minerals, and food.

Q12. What are underground stems?

Answer: Underground stems are modified stems growing below the soil surface, functioning in storage, perennation, and vegetative propagation, such as rhizome and tuber.

Q13. What is a rhizome?

Answer: Rhizome is a horizontal underground stem with nodes and internodes, storing food and enabling vegetative propagation, as seen in ginger.

Q14. What is a tuber?

Answer: Tuber is a swollen underground stem storing food, bearing eyes that represent nodes, and helps in vegetative propagation, as seen in potato.

Q15. What is a bulb?

Answer: Bulb is an underground stem with a short disc-like stem and fleshy scale leaves storing food, commonly seen in onion.

Q16. What are aerial stem modifications?

Answer: Aerial stem modifications include tendrils for climbing, thorns for protection, and phylloclades for photosynthesis, seen in plants like cucurbits and cactus.

Q17. What is a tendril?

Answer: Tendrils are slender, coiled stem modifications that help plants climb and support themselves by twining around nearby structures.

Q18. What is a phylloclade?

Answer: Phylloclade is a flattened or cylindrical stem modification that performs photosynthesis and stores water, commonly found in xerophytic plants like Opuntia.

Q19. What are subaerial stems?

Answer: Subaerial stems partially grow above ground and aid in vegetative propagation, including runner, stolon, sucker, and offset.

Q20. Give one function of stem modification.

Answer: Stem modifications help in storage of food, vegetative propagation, protection, photosynthesis, and survival during unfavourable environmental conditions.

Section III: Leaf (Questions 21–30)

Q21. Define leaf.

Answer: Leaf is a flattened, lateral structure borne on the stem, mainly responsible for photosynthesis, transpiration, and gaseous exchange.

Q22. What are the main parts of a leaf?

Answer: A leaf consists of three main parts: leaf base, petiole, and lamina, each performing specific structural and physiological functions.

Q23. What is venation?

Answer: Venation refers to the arrangement of veins and veinlets in the leaf lamina, which helps in conduction and provides mechanical support.

Q24. Define reticulate venation.

Answer: Reticulate venation is a network-like arrangement of veins in the leaf lamina, commonly found in dicotyledonous plants.

Q25. What is parallel venation?

Answer: Parallel venation is a type of venation where veins run parallel to each other, commonly seen in monocotyledonous plants.

Q26. What is phyllotaxy?

Answer: Phyllotaxy is the arrangement of leaves on the stem or branch, ensuring maximum exposure to sunlight for efficient photosynthesis.

Q27. Name the types of phyllotaxy.

Answer: The three main types of phyllotaxy are alternate, opposite, and whorled, based on the number and arrangement of leaves at nodes.

Q28. What is a simple leaf?

Answer: A simple leaf has a single undivided lamina, and incisions, if present, do not reach the midrib or leaf base.

Q29. What is a compound leaf?

Answer: A compound leaf has its lamina divided into distinct leaflets, which may be arranged pinnately or palmately.

Q30. Mention one modification of leaf.

Answer: Leaves may modify into tendrils for climbing, spines for protection, storage leaves for food, or insect-trapping leaves in insectivorous plants.

Section IV: Inflorescence (Questions 31–35)

Q31. Define inflorescence.

Answer: Inflorescence is the arrangement of flowers on the floral axis or peduncle, determining the sequence and pattern of flowering.

Q32. What is racemose inflorescence?

Answer: Racemose inflorescence has an indeterminate main axis that continues to grow, bearing flowers in acropetal succession.

Q33. What is cymose inflorescence?

Answer: Cymose inflorescence has a determinate main axis that ends in a flower, with subsequent flowers arranged in basipetal succession.

Q34. Name a special type of inflorescence.

Answer: Special types of inflorescence include cyathium, hypanthodium, and verticillaster, found in plants like Euphorbia, Ficus, and Ocimum.

Q35. What is hypanthodium?

Answer: Hypanthodium is a special inflorescence where flowers are borne on the inner surface of a fleshy receptacle, as seen in fig.

Section V: Flower, Fruit, Seed & Floral Formula (Questions 36–50)

Q36. Define flower.

Answer: Flower is the reproductive part of angiosperms, consisting of four whorls, and is responsible for sexual reproduction and seed formation.

Q37. What are the four whorls of a flower?

Answer: The four whorls of a flower are calyx, corolla, androecium, and gynoecium, arranged concentrically on the thalamus.

Q38. What is a bisexual flower?

Answer: A bisexual flower contains both male and female reproductive organs, namely androecium and gynoecium, within the same flower.

Q39. What is actinomorphic symmetry?

Answer: Actinomorphic flowers can be divided into two equal halves by any vertical plane passing through the centre, showing radial symmetry.

Q40. Define hypogynous flower.

Answer: Hypogynous flower has a superior ovary, with sepals, petals, and stamens arising below the ovary on the thalamus.

Q41. What is a fruit?

Answer: Fruit is a mature ovary formed after fertilisation, enclosing seeds and aiding in their protection and dispersal.

Q42. What is a simple fruit?

Answer: A simple fruit develops from the ovary of a single flower and may be dry or fleshy depending on pericarp nature.

Q43. What is a seed?

Answer: Seed is a fertilised ovule containing an embryo, reserve food, and protective seed coat, capable of developing into a new plant.

Q44. What is an albuminous seed?

Answer: Albuminous seeds retain endosperm even after maturation, providing nourishment to the embryo, as seen in maize and castor.

Q45. What is an exalbuminous seed?

Answer: Exalbuminous seeds lack endosperm at maturity because food is stored in cotyledons, as seen in pea and gram.

Q46. Define floral formula.

Answer: Floral formula is a symbolic representation that expresses the structure of a flower, including symmetry, sexuality, and number of floral parts.

Q47. What does the symbol ⊕ indicate in floral formula?

Answer: The symbol ⊕ in a floral formula represents actinomorphic or radially symmetrical flowers.

Q48. What does K, C, A, and G represent?

Answer: In floral formula, K denotes calyx, C denotes corolla, A denotes androecium, and G denotes gynoecium.

Q49. What is a floral diagram?

Answer: Floral diagram is a graphical representation showing the arrangement, number, and fusion of floral parts in relation to the mother axis.

Q50. Why is floral formula important?

Answer: Floral formula helps in quick identification, classification, and comparison of flowers, making it useful for taxonomy and exam-oriented revisions.