Botany Unit - II Pteridophytes

BOTANY UNIT – II PTERIDOPHYTES NO. OF. QUESTIONS: 215 Classification of Pteriodophytes ( Reimer, 1954). Stelar evolution. Telome theory. Sorus – Origin, types and sporangial development. Heterospory and seed habit – Alternation of generations. Apogamy, Apospory and parthenogenesis in Pteriodophytes. Comparative morphology, anatomy, reproduction and evolutionary studies of the following groups: Psilopsida, Lycopsida, Sphenopsida and Pteropsida. Economic importance of Pteridophytes. 1. Pteridophytes are classified by Reimer (1954) into ____ classes. a) Two b) Three c) Four d) Five Correct Answer: c) Four Explanation: Reimer (1954) classified Pteridophytes into four classes—Psilopsida, Lycopsida, Sphenopsida, and Pteropsida. 2. The class Psilopsida is characterized by the absence of _____. a) Roots b) Stems c) Leaves d) Spores Correct Answer: a) Roots Explanation: Psilopsida members, like Psilotum, lack true roots and have rhizomes with rhizoids for absorption. 3. The members of class Lycopsida are commonly called _____. a) Club mosses b) Whisk ferns c) Horsetails d) True ferns Correct Answer: a) Club mosses Explanation: Lycopsida includes plants like Lycopodium and Selaginella, which resemble mosses but have vascular tissues. 4. In Sphenopsida, the reproductive structures are borne on specialized structures called _____. a) Sporangia b) Strobili c) Sori d) Rhizophores Correct Answer: b) Strobili Explanation: Sphenopsida (e.g., Equisetum) have cone-like structures called strobili that contain reproductive spores. 5. Pteropsida includes the most advanced Pteridophytes, commonly known as _____. a) Whisk ferns b) Club mosses c) Horsetails d) True ferns Correct Answer: d) True ferns Explanation: Pteropsida, such as Dryopteris and Pteris, are true ferns with well-developed leaves (fronds). 6. The dominant generation in Pteridophytes is the _____. a) Gametophyte b) Sporophyte c) Zygote d) Prothallus Correct Answer: b) Sporophyte Explanation: In Pteridophytes, the sporophyte is the dominant phase, unlike bryophytes where the gametophyte is dominant. 7. The spores of homosporous Pteridophytes develop into a _____. a) Unisexual gametophyte b) Bisexual gametophyte c) Sporophyte directly d) Zygote Correct Answer: b) Bisexual gametophyte Explanation: Homosporous ferns produce spores that develop into a gametophyte with both antheridia (male) and archegonia (female). 8. Selaginella and Salvinia are examples of _____. a) Homosporous Pteridophytes b) Heterosporous Pteridophytes c) Seed-bearing Pteridophytes d) Non-vascular Pteridophytes Correct Answer: b) Heterosporous Pteridophytes Explanation: These plants produce two types of spores—microspores (male) and megaspores (female). 9. The term "prothallus" refers to the _____. a) Sporophytic leaf b) Gametophytic structure c) Spore capsule d) Root system Correct Answer: b) Gametophytic structure Explanation: Prothallus is the gametophyte of Pteridophytes, where gametes are produced. 10. In Equisetum, the aerial stems contain silica, making them useful as _____. a) Medicine b) Scouring material c) Fertilizer d) Insecticide Correct Answer: b) Scouring material Explanation: The rough texture due to silica deposits makes Equisetum stems useful for cleaning and polishing. 11. Which of the following Pteridophytes reproduces vegetatively through rhizomes? a) Selaginella b) Lycopodium c) Equisetum d) Psilotum Correct Answer: c) Equisetum Explanation: Equisetum propagates vegetatively through underground rhizomes. 12. The following is NOT a characteristic of Pteridophytes; a) Vascular tissues b) Flowering structures c) Alternation of generations d) Independent gametophyte Correct Answer: b) Flowering structures Explanation: Pteridophytes do not bear flowers; they reproduce via spores. 13. The leaves of Pteropsida are commonly called _____. a) Fronds b) Needles c) Microphylls d) Sporophylls Correct Answer: a) Fronds Explanation: The large, divided leaves of ferns are called fronds. 14. Heterospory is a precursor to the evolution of _____. a) Spores b) Seeds c) Rhizoids d) Flowers Correct Answer: b) Seeds Explanation: Heterospory led to seed habit by producing specialized male and female gametophytes. 15. The vascular tissues of Pteridophytes include _____. a) Xylem and Phloem b) Tracheids only c) Cambium only d) Sieve tubes only Correct Answer: a) Xylem and Phloem Explanation: Pteridophytes have a well-developed vascular system for conduction of water (xylem) and food (phloem). 16. Classes of Pteridophytes is considered the most primitive: a) Pteropsida b) Lycopsida c) Psilopsida d) Sphenopsida Correct Answer: c) Psilopsida Explanation: Psilopsida (e.g., Psilotum) are the most primitive Pteridophytes, lacking true roots and leaves. 17. The reproductive organs of Pteridophytes are called _____. a) Sporangia b) Cones c) Embryos d) Bulbs Correct Answer: a) Sporangia Explanation: Sporangia are structures where spores are produced, helping in reproduction. 18. The following is an example of a homosporous Pteridophyte: a) Selaginella b) Salvinia c) Lycopodium d) Marsilea Correct Answer: c) Lycopodium Explanation: Lycopodium produces only one type of spore, leading to a bisexual gametophyte. 19. In the life cycle of a fern, fertilization occurs in the presence of _____. a) Wind b) Water c) Insects d) Sunlight Correct Answer: b) Water Explanation: Water is required for sperm to swim to the egg in the archegonium for fertilization. 20. The following statements about Pteridophytes is true: a) They produce seeds b) They have vascular tissues c) Their gametophyte is dominant d) They bear flowers Correct Answer: b) They have vascular tissues Explanation: Pteridophytes have well-developed xylem and phloem, making them the first vascular plants. 21. A major ecological advantage of Pteridophytes; a) They contribute to nitrogen fixation b) They prevent soil erosion c) They produce large seeds d) They attract pollinators Correct Answer: b) They prevent soil erosion Explanation: Pteridophytes, especially ferns, help stabilize soil with their extensive root and rhizome systems, preventing erosion. 22. Pteridophytes serve as a bridge between which two groups of plants? a) Algae and Bryophytes b) Bryophytes and Gymnosperms c) Gymnosperms and Angiosperms d) Algae and Fungi Correct Answer: b) Bryophytes and Gymnosperms Explanation: Pteridophytes are considered evolutionary intermediates between non-vascular Bryophytes and seed-bearing Gymnosperms. 23. A medicinal use of Pteridophytes? a) Treatment of burns b) Production of antibiotics c) Synthesis of vitamins d) Increasing crop yield Correct Answer: a) Treatment of burns Explanation: Some ferns, like Osmunda regalis, are used in traditional medicine for treating burns and wounds. 24. A major disadvantage of Pteridophytes in reproduction___________ a) They require insects for pollination b) They depend on water for fertilization c) They produce weak seeds d) They cannot reproduce vegetatively Correct Answer: b) They depend on water for fertilization Explanation: Pteridophytes need water for sperm motility, limiting their ability to reproduce in dry environments. 25. Some Pteridophytes used in gardening and landscaping ___________ a) Their flowers attract bees b) They require minimal water c) They have ornamental foliage d) They produce edible fruits Correct Answer: c) They have ornamental foliage Explanation: Many ferns and lycopods are grown for their decorative fronds and ability to thrive in shaded environments. 26. What limits the geographical distribution of Pteridophytes? a) Dependence on wind for seed dispersal b) Requirement for moist environments c) Slow growth rate d) Lack of vascular tissues Correct Answer: b) Requirement for moist environments Explanation: Because they rely on water for reproduction, Pteridophytes are mostly found in humid and shaded habitats. 27. Economic uses is associated with Pteridophytes _______________ a) Paper production b) Coal formation c) Rubber extraction d) Fiber production Correct Answer: b) Coal formation Explanation: Ancient Pteridophytes, such as tree ferns and club mosses, contributed to the formation of coal deposits. 28. A structural disadvantage of Pteridophytes compared to seed plants_______ a) They lack vascular tissues b) They do not produce true roots c) They lack protective seed coats d) They have weak stems Correct Answer: c) They lack protective seed coats Explanation: Unlike Gymnosperms and Angiosperms, Pteridophytes reproduce via spores, which are more vulnerable to environmental conditions. 29. Pteridophyte is commonly used in biological research_________ a) Lycopodium b) Adiantum c) Equisetum d) Selaginella Correct Answer: d) Selaginella Explanation: Selaginella is studied for its unique heterospory and its role in plant evolution. 30. Pteridophytes contribute to forest ecosystems_____________ a) They act as primary producers b) They fix atmospheric nitrogen c) They decompose organic matter d) They prevent wildfires Correct Answer: a) They act as primary producers Explanation: Pteridophytes, like ferns, contribute to the food web by photosynthesizing and providing oxygen and organic matter. 31. A major reproductive limitation of Pteridophytes____________ a) They produce very few spores b) They require two different plants for fertilization c) Their gametophyte stage is independent and fragile d) They cannot undergo vegetative propagation Correct Answer: c) Their gametophyte stage is independent and fragile Explanation: The gametophyte (prothallus) is small and delicate, making it vulnerable to environmental changes. 32. Pteridophyte has been traditionally used as a food source; a) Marsilea b) Psilotum c) Lycopodium d) Adiantum Correct Answer: a) Marsilea Explanation: Marsilea (water clover) produces edible sporocarps, which are consumed in some regions. 33. Pteridophytes not dominant in present-day plant communities; a) They do not produce flowers and seeds b) They are easily eaten by herbivores c) They lack vascular tissues d) They grow too slowly Correct Answer: a) They do not produce flowers and seeds Explanation: Seed plants (Gymnosperms and Angiosperms) outcompete Pteridophytes due to their more advanced reproductive structures. 34. The following is a benefit of heterospory in Pteridophytes; a) It increases genetic diversity b) It speeds up vegetative reproduction c) It eliminates the need for water in fertilization d) It reduces the need for spores Correct Answer: a) It increases genetic diversity Explanation: Heterospory allows separate male and female gametophytes, leading to greater genetic variation and better adaptation. 35. Pteridophytes indicates their evolutionary link to higher plants: a) Presence of spores b) Development of vascular tissues c) Lack of roots d) Independent gametophyte stage Correct Answer: b) Development of vascular tissues Explanation: The presence of xylem and phloem in Pteridophytes marks an evolutionary step toward seed plants. 36. Pteridophytes were the first plants to develop true _____. a) Seeds b) Vascular tissues c) Flowers d) Fruits Correct Answer: b) Vascular tissues Explanation: Pteridophytes are the earliest plants to have well-developed xylem and phloem for water and nutrient transport. 37. Characteristic of Pteridophytes limits their ability to colonize dry environments a) Lack of vascular tissues b) Dependence on water for fertilization c) Absence of photosynthesis d) Inability to produce oxygen Correct Answer: b) Dependence on water for fertilization Explanation: Since their motile sperm require water to reach the egg, Pteridophytes are mostly found in moist environments. 38. The presence of both microspores and megaspores in certain Pteridophytes is called _____. a) Homospory b) Heterospory c) Isogamy d) Vegetative reproduction Correct Answer: b) Heterospory Explanation: Heterospory, seen in Selaginella and Salvinia, is an evolutionary step toward seed formation in higher plants. 39. The underground stem found in many Pteridophytes, such as ferns, is called a _____. a) Rhizome b) Sporophyll c) Prothallus d) Petiole Correct Answer: a) Rhizome Explanation: A rhizome is a modified underground stem that helps in vegetative reproduction and storage of nutrients. 40. Pteridophytes are mainly found in _____. a) Dry deserts b) Aquatic environments c) Moist and shady habitats d) High altitudes only Correct Answer: c) Moist and shady habitats Explanation: Due to their requirement for water in reproduction, Pteridophytes thrive in damp, shaded environments like forests. 41. The basic unit of vascular organization in Pteridophytes is called the _____. a) Phloem b) Xylem c) Stele d) Cortex Correct Answer: c) Stele Explanation: The stele is the central vascular tissue system that consists of xylem, phloem, and other associated tissues. 42. The simplest and most primitive type of stele found in Pteridophytes is the _____. a) Siphonostele b) Protostele c) Dictyostele d) Eustele Correct Answer: b) Protostele Explanation: Protostele is considered the most primitive type, consisting of a solid core of xylem surrounded by phloem. 43. Stele is characterized by a central xylem core surrounded by phloem_____ a) Amphiphloic siphonostele b) Haplostele c) Dictyostele d) Eustele Correct Answer: b) Haplostele Explanation: Haplostele is the simplest form of protostele, with a cylindrical xylem core surrounded by phloem. 44. A protostele with star-shaped xylem is called _____. a) Actinostele b) Plectostele c) Siphonostele d) Eustele Correct Answer: a) Actinostele Explanation: Actinostele is a variation of protostele where the xylem forms a star-like shape, seen in some early Pteridophytes. 45. The stele in which the central core of vascular tissue is interrupted by leaf gaps is called _____. a) Protostele b) Siphonostele c) Actinostele d) Eustele Correct Answer: b) Siphonostele Explanation: In siphonostele, the vascular cylinder contains a pith, and leaf gaps are present, allowing for more efficient transport. 46. Amphiphloic siphonostele is characterized by phloem present on _____. a) The outer side of xylem only b) The inner side of xylem only c) Both inner and outer sides of xylem d) Neither side of xylem Correct Answer: c) Both inner and outer sides of xylem Explanation: Amphiphloic siphonostele has phloem surrounding the xylem on both inner and outer sides, improving conduction efficiency. 47. Stele is found in ferns like Osmunda and Marsilea; a) Protostele b) Eustele c) Amphiphloic siphonostele d) Actinostele Correct Answer: c) Amphiphloic siphonostele Explanation: Amphiphloic siphonostele is common in ferns, where phloem is found on both inner and outer sides of the xylem. 48. Plectostele is a modification of _____. a) Haplostele b) Actinostele c) Siphonostele d) Eustele Correct Answer: b) Actinostele Explanation: Plectostele is a more advanced form of actinostele where the xylem appears broken into separate plates or strands. 49. The most advanced type of stele found in seed plants is _____. a) Eustele b) Plectostele c) Protostele d) Dictyostele Correct Answer: a) Eustele Explanation: Eustele consists of separate vascular bundles arranged in a ring, as seen in Gymnosperms and Angiosperms. 50. The stele type in which the vascular cylinder is broken into distinct vascular bundles is called _____. a) Protostele b) Dictyostele c) Actinostele d) Eustele Correct Answer: b) Dictyostele Explanation: Dictyostele consists of multiple vascular strands separated by leaf gaps, commonly found in ferns. 51. Stele represents the transition from Pteridophytes to seed plants; a) Protostele b) Dictyostele c) Eustele d) Haplostele Correct Answer: c) Eustele Explanation: Eustele, found in seed plants, evolved from siphonosteles and consists of discrete vascular bundles. 52. In dictyostele, the individual vascular strands are called _____. a) Xylem rings b) Leaf gaps c) Meristeles d) Cambium Correct Answer: c) Meristeles Explanation: In dictyostele, the vascular cylinder breaks into smaller units called meristeles, each surrounded by an endodermis. 53. An evolutionary advantage of dictyostele a) It provides more efficient conduction b) It allows better mechanical support c) It permits larger leaf formation d) All of the above Correct Answer: d) All of the above Explanation: Dictyostele improves conduction, mechanical strength, and allows larger leaves by forming multiple vascular strands. 54. Stele is found in primitive club mosses like Lycopodium; a) Protostele b) Dictyostele c) Siphonostele d) Eustele Correct Answer: a) Protostele Explanation: Lycopodium has a protostele, the simplest stele type, which consists of a solid core of xylem surrounded by phloem. 55. In which of the following stele types is the pith absent? a) Siphonostele b) Dictyostele c) Protostele d) Eustele Correct Answer: c) Protostele Explanation: Protostele lacks a pith, as it consists of a solid core of xylem and phloem, making it the most primitive stele type. 56. The presence of leaf gaps is a characteristic feature of _____. a) Protostele b) Siphonostele c) Plectostele d) Actinostele Correct Answer: b) Siphonostele Explanation: Siphonostele is characterized by the presence of leaf gaps, which are interruptions in the vascular cylinder where leaves arise. 57. The stele type that consists of scattered vascular bundles, as seen in monocots, is called _____. a) Eustele b) Atactostele c) Protostele d) Dictyostele Correct Answer: b) Atactostele Explanation: Atactostele is an advanced type of stele where vascular bundles are scattered throughout the stem, commonly found in monocots. 58. Types of stele is commonly found in ferns like Pteris and Dryopteris; a) Dictyostele b) Actinostele c) Plectostele d) Haplostele Correct Answer: a) Dictyostele Explanation: Ferns such as Pteris and Dryopteris possess dictyostele, where vascular strands (meristeles) are separated by leaf gaps. 59. The evolutionary trend in stelar evolution progresses from _____. a) Protostele ? Siphonostele ? Dictyostele ? Eustele b) Siphonostele ? Protostele ? Eustele ? Dictyostele c) Dictyostele ? Eustele ? Protostele ? Siphonostele d) Eustele ? Protostele ? Siphonostele ? Dictyostele Correct Answer: a) Protostele ? Siphonostele ? Dictyostele ? Eustele Explanation: Stelar evolution shows a transition from simple protostele to complex eustele, enhancing conduction efficiency and leaf development. 60. The modification of siphonostele where multiple meristeles are formed due to leaf gaps is called _____. a) Haplostele b) Actinostele c) Dictyostele d) Plectostele Correct Answer: c) Dictyostele Explanation: Dictyostele is a modification of siphonostele where vascular tissue is divided into multiple meristeles due to numerous leaf gaps. 61. The Telome Theory was proposed by _____. a) Bower b) Zimmermann c) Sporne d) Strasburger Correct Answer: b) Zimmermann Explanation: Walter Zimmermann proposed the Telome Theory to explain the evolution of vascular plant structures from simple telomic systems. 62. The basic structural unit in Telome Theory is called a _____. a) Leaf b) Telome c) Rhizome d) Sporophyll Correct Answer: b) Telome Explanation: A telome is the terminal branch of a primitive plant that serves as the fundamental unit of plant morphology and evolution. 63. According to Telome Theory, early vascular plants consisted of _____. a) True leaves and stems b) Roots, stems, and leaves c) Dichotomously branching systems d) Flowers and fruits Correct Answer: c) Dichotomously branching systems Explanation: Early vascular plants had simple dichotomous branching systems composed of telomes and mesomes. 64. A telome that bears sporangia is called a _____. a) Phyllome b) Fertile telome c) Vegetative telome d) Stipule Correct Answer: b) Fertile telome Explanation: Fertile telomes are those that bear reproductive structures such as sporangia, playing a role in reproduction. 65. A telome that does not bear sporangia and is involved in photosynthesis is called a _____. a) Sterile telome b) Fertile telome c) Strobilus d) Sporophyll Correct Answer: a) Sterile telome Explanation: Sterile telomes are those that do not bear reproductive structures and instead function in photosynthesis. 66. The fusion of telomes into a flattened, leaf-like structure is called _____. a) Overtopping b) Planation c) Syngenesis d) Reduction Correct Answer: b) Planation Explanation: Planation is the process where telomes become arranged in a single plane, leading to the formation of leaf-like structures. 67. The evolutionary process where one branch grows more dominantly than the other is called _____. a) Dichotomy b) Reduction c) Overtopping d) Recurvation Correct Answer: c) Overtopping Explanation: Overtopping occurs when one telome branch grows more dominantly than others, leading to the formation of a main stem. 68. The transformation of individual telomes into a single, compact structure is known as _____. a) Syngenesis b) Reduction c) Recurvation d) Overtopping Correct Answer: a) Syngenesis Explanation: Syngenesis is the evolutionary process where multiple telomes fuse to form complex structures like leaves. 69. According to Telome Theory, compound leaves evolved through the process of _____. a) Overtopping and planation b) Reduction and syngenesis c) Enation and vascularization d) Dichotomy and modification Correct Answer: a) Overtopping and planation Explanation: The combination of overtopping (branch dominance) and planation (flattening) led to the evolution of compound leaves. 70. The following evolutionary processes led to the formation of megaphylls a) Overtopping, planation, and syngenesis b) Reduction and dichotomy c) Enation and vascularization d) Recurvation and syngenesis Correct Answer: a) Overtopping, planation, and syngenesis Explanation: Megaphylls evolved through the combined effects of overtopping, planation, and fusion of telomes (syngenesis). 71. The process in which telomes became reduced in number and size over time is called _____. a) Reduction b) Syngenesis c) Dichotomy d) Planation Correct Answer: a) Reduction Explanation: Reduction is the evolutionary trend where certain telomes decrease in number and size, leading to simpler structures. 72. Telome Theory explains the evolution of which plant structures? a) Flowers b) Vascular tissues c) Leaves, stems, and roots d) Chloroplasts Correct Answer: c) Leaves, stems, and roots Explanation: Telome Theory provides an evolutionary framework for understanding the origin of major plant organs like leaves, stems, and roots. 73. The Telome Theory primarily explains the evolution of vascular plants from _____. a) Bryophytes b) Algae c) Thallophytes d) Gymnosperms Correct Answer: a) Bryophytes Explanation: The Telome Theory suggests that vascular plants evolved from bryophyte-like ancestors with simple branching systems. 74. According to Telome Theory, microphylls evolved through which process? a) Enation and vascularization b) Planation and overtopping c) Reduction and syngenesis d) Dichotomy and modification Correct Answer: a) Enation and vascularization Explanation: Microphylls (small leaves with a single vein) evolved through enation (outgrowths) and the later development of vascular tissues. 75. The following is NOT an evolutionary process in the Telome Theory; a) Overtopping b) Planation c) Syngenesis d) Apomixis Correct Answer: d) Apomixis Explanation: Apomixis refers to asexual reproduction without fertilization, which is unrelated to telome evolution. 76. The concept of Telome Theory primarily applies to the evolution of which plant group? a) Algae b) Bryophytes c) Pteridophytes d) Angiosperms Correct Answer: c) Pteridophytes Explanation: Telome Theory is mainly used to explain the evolution of vascular plant structures, particularly in Pteridophytes (ferns and their allies). 77. The vascular strand connecting telomes in primitive plants is known as _____. a) Mesome b) Rhizome c) Enation d) Leaf trace Correct Answer: a) Mesome Explanation: Mesomes are the vascular strands connecting telomes in early vascular plants, facilitating transport between them. 78. Which of the following processes is responsible for the evolution of pinnate leaves? a) Overtopping and dichotomy b) Planation and syngenesis c) Enation and vascularization d) Reduction and recurvation Correct Answer: b) Planation and syngenesis Explanation: Pinnate leaves evolved when telomes arranged in a single plane (planation) fused together (syngenesis) to form a leaf structure. 79. Which of the following best describes the main significance of Telome Theory? a) It explains how leaves and reproductive structures evolved in vascular plants b) It describes how flowers evolved in Angiosperms c) It explains the origin of root hairs d) It is related to seed germination Correct Answer: a) It explains how leaves and reproductive structures evolved in vascular plants Explanation: Telome Theory provides a framework for understanding how leaves, stems, and reproductive organs evolved from primitive branching systems. 80. In Telome Theory, the formation of a main axis (stem) due to one branch growing more dominantly than others is called _____. a) Planation b) Overtopping c) Reduction d) Dichotomy Correct Answer: b) Overtopping Explanation: Overtopping refers to the process where one branch of a dichotomously branching system becomes dominant, leading to the formation of a main stem. 81. The term "sorus" refers to a cluster of __________. a) Roots b) Sporangia c) Leaves d) Stems Answer: b) Sporangia Explanation: A sorus is a group of sporangia, commonly found on the underside of fern fronds, which are responsible for spore production. 82. The sorus is mainly found in __________. a) Bryophytes b) Gymnosperms c) Pteridophytes d) Angiosperms Answer: c) Pteridophytes Explanation: Pteridophytes (ferns and related plants) have sori that contain sporangia for spore dispersal. 83. In pteridophytes, the sorus develops on the __________ of the leaves. a) Upper surface b) Margins c) Underside d) Petiole Answer: c) Underside Explanation: Most ferns have sori on the underside of their fronds to protect the developing spores. 84. The protective covering over a sorus is called the __________. a) Prothallus b) Indusium c) Sporangium d) Sporophyll Answer: b) Indusium Explanation: The indusium is a thin membrane that protects the sporangia in certain ferns. 85. The origin of a sorus is primarily __________ in nature. a) Gametophytic b) Sporophytic c) Haploid d) Symbiotic Answer: b) Sporophytic Explanation: The sorus is part of the sporophyte generation and is responsible for spore production. 86. The arrangement of sporangia in a sorus can be __________. a) Random b) Linear c) Circular d) All of the above Answer: d) All of the above Explanation: Sori can have different arrangements, depending on the species of ferns. 87. The main function of the sorus is __________. a) Photosynthesis b) Nitrogen fixation c) Spore production d) Water conduction Answer: c) Spore production Explanation: The sorus contains sporangia, which produce spores for reproduction. 88. A false sorus is also known as __________. a) Coenosorus b) Synangium c) Indusium d) Sporophyll Answer: a) Coenosorus Explanation: A coenosorus is a collection of fused sori found in some ferns. 89. The sori of Dryopteris are protected by __________. a) Calyptra b) Indusium c) Elaters d) Rhizoids Answer: b) Indusium Explanation: Dryopteris (a common fern) has sori covered by a kidney-shaped indusium. 90. The sori in Polypodium species are typically __________. a) Covered b) Naked c) Spiral d) In a straight line Answer: b) Naked Explanation: Polypodium species have exposed sori without an indusium. 91. The development of a sorus is controlled by __________. a) Environmental factors b) Genetic factors c) Both (a) and (b) d) Neither (a) nor (b) Answer: c) Both (a) and (b) Explanation: Sori formation is influenced by genetic programming and environmental conditions like humidity. 92. The annulus in the sporangium helps in __________. a) Spore dispersal b) Photosynthesis c) Water absorption d) Root anchorage Answer: a) Spore dispersal Explanation: The annulus, a ring of thick-walled cells, helps release spores by creating tension. 93. A sorus without an indusium is called __________. a) True sorus b) Naked sorus c) False sorus d) Indusiate sorus Answer: b) Naked sorus Explanation: Some ferns, like Polypodium, have sori without a protective covering. 94. In some ferns, sori are arranged along the margins of the leaflets. This arrangement is called __________. a) Acrostichoid b) Marginal c) Peltate d) Superficial Answer: b) Marginal Explanation: Marginal sori are located along the leaf margin, often covered by a reflexed leaf edge. 95. The sori of Pteridium (bracken fern) are protected by __________. a) Reflexed leaf margins b) Indusium c) Annulus d) Elaters Answer: a) Reflexed leaf margins Explanation: In Pteridium, sori are hidden under the rolled edges of the fronds. 96. The type of sorus where sporangia mature at different times is called __________. a) Simple b) Mixed c) Gradate d) Eusporangiate Answer: c) Gradate Explanation: In a gradate sorus, sporangia develop in succession, leading to different stages of maturity within the same sorus. 97. A group of sporangia that develop from a common placenta is called __________. a) Indusium b) Sporocarp c) Synangium d) Coenosorus Answer: c) Synangium Explanation: A synangium consists of fused sporangia, commonly seen in Psilotum and some other pteridophytes. 98. The sori in Marsilea are enclosed in specialized structures called __________. a) Sporocarp b) Indusium c) Rhizome d) Annulus Answer: a) Sporocarp Explanation: Marsilea has sori enclosed in hard, drought-resistant structures called sporocarps that help in spore dispersal. 99. The reproductive cells inside the sporangia of a sorus are called __________. a) Zygotes b) Spores c) Gametes d) Protonema Answer: b) Spores Explanation: Spores are the haploid reproductive cells produced in sporangia, responsible for germinating into gametophytes. 100. In the Polypodiaceae family, the sori are typically arranged in a __________ pattern. a) Linear b) Circular c) Random d) All of the above Answer: d) All of the above Explanation: Different genera in Polypodiaceae exhibit diverse sorus arrangements, including linear, circular, and random patterns. 101. Pteridophytes are classified into how many major groups based on their structure and reproduction? a) Two b) Three c) Four d) Five Answer: c) Four Explanation: Pteridophytes are classified into Lycopsida, Sphenopsida, Psilopsida, and Pteropsida based on structural and reproductive differences. 102. Sporangia in pteridophytes develop by which two main types of development? a) Exogenous and endogenous b) Eusporangiate and leptosporangiate c) Homosporous and heterosporous d) Megasporangia and microsporangia Answer: b) Eusporangiate and leptosporangiate Explanation: Eusporangiate sporangia arise from multiple cells, while leptosporangiate sporangia develop from a single initial cell. 103. The primitive type of sporangial development in pteridophytes is __________. a) Eusporangiate b) Leptosporangiate c) Homosporous d) Heterosporous Answer: a) Eusporangiate Explanation: Eusporangiate development is considered more primitive because the sporangia originate from multiple initial cells. 104. The more advanced form of sporangial development in ferns is __________. a) Eusporangiate b) Leptosporangiate c) Homosporous d) Isosporous Answer: b) Leptosporangiate Explanation: Leptosporangiate development is more advanced and occurs in Filicales (true ferns), where the sporangium arises from a single initial cell. 105. Lycopodium exhibits which type of sporangial development? a) Eusporangiate b) Leptosporangiate c) Homosporous d) Heterosporous Answer: a) Eusporangiate Explanation: Lycopodium has eusporangiate development, meaning its sporangia arise from multiple initial cells. 106. The sporangia of Selaginella and Salvinia belong to which type of reproductive strategy? a) Homosporous b) Heterosporous c) Leptosporangiate d) Eusporangiate Answer: b) Heterosporous Explanation: Selaginella and Salvinia produce two types of spores—megaspores and microspores, making them heterosporous. 107. The development of spores within a single type of sporangium is called __________. a) Heterospory b) Homospory c) Eusporangiate d) Isospory Answer: b) Homospory Explanation: Homospory occurs when a plant produces only one type of spore, which can develop into a bisexual gametophyte. 108. The genera Equisetum and Psilotum exhibit which type of sporangial development? a) Eusporangiate b) Leptosporangiate c) Homosporous d) Heterosporous Answer: a) Eusporangiate Explanation: Equisetum and Psilotum develop their sporangia from multiple initial cells, making them eusporangiate. 109. Which of the following pteridophytes is heterosporous? a) Lycopodium b) Pteridium c) Selaginella d) Adiantum Answer: c) Selaginella Explanation: Selaginella produces two types of spores, making it heterosporous. 110. The structure in which sporangia are grouped together is called a __________. a) Strobilus b) Sorus c) Sporocarp d) Prothallus Answer: b) Sorus Explanation: In ferns, sori are clusters of sporangia found on the underside of fronds. 111. The strobilus in Lycopodium consists of __________. a) Sori b) Sporocarps c) Sporophylls d) Indusium Answer: c) Sporophylls Explanation: The strobilus (cone-like structure) in Lycopodium contains sporophylls, which bear sporangia. 112. The pteridophytes belongs to the leptosporangiate type; a) Lycopodium b) Psilotum c) Pteridium d) Equisetum Answer: c) Pteridium Explanation: Pteridium (a fern) has leptosporangiate development, where sporangia arise from a single initial cell. 113. Pteridophytes has sporocarps instead of sori a) Marsilea b) Dryopteris c) Adiantum d) Equisetum Answer: a) Marsilea Explanation: Marsilea produces sporocarps, which are drought-resistant structures containing sori. 114. The presence of an annulus in the sporangium is characteristic of which type of development? a) Eusporangiate b) Leptosporangiate c) Homosporous d) Heterosporous Answer: b) Leptosporangiate Explanation: Annulus is a specialized ring of cells that aids in spore dispersal in leptosporangiate ferns. 115. The sporangia of heterosporous pteridophytes produce __________. a) Only microspores b) Only megaspores c) Both microspores and megaspores d) Haploid gametes Answer: c) Both microspores and megaspores Explanation: Heterosporous plants, such as Selaginella and Marsilea, produce both microspores (male) and megaspores (female). 116. The production of two different types of spores in pteridophytes is called __________. a) Homospory b) Heterospory c) Eusporangiate development d) Isospory Answer: b) Heterospory Explanation: Heterospory refers to the production of megaspores (female) and microspores (male), seen in some pteridophytes. 117. Which of the following pteridophytes is heterosporous? a) Lycopodium b) Selaginella c) Pteridium d) Dryopteris Answer: b) Selaginella Explanation: Selaginella is a heterosporous pteridophyte producing both microspores and megaspores. 118. The following is an advantage of heterospory; a) Increased water dependence b) Formation of separate male and female gametophytes c) Reduced gametophyte survival d) Gametophyte exposed to external environment Answer: b) Formation of separate male and female gametophytes Explanation: Heterospory promotes cross-fertilization by producing separate male and female gametophytes, leading to genetic diversity. 119. In heterosporous plants, the megaspores develop into __________. a) Male gametophytes b) Female gametophytes c) Sporophytes d) Embryos directly Answer: b) Female gametophytes Explanation: Megaspores germinate into female gametophytes, which produce archegonia and eggs. 120. Which of the following pteridophytes does not exhibit heterospory? a) Salvinia b) Marsilea c) Lycopodium d) Azolla Answer: c) Lycopodium Explanation: Lycopodium is homosporous, producing only one type of spore. 121. Seed habit is considered to have originated in which type of pteridophytes? a) Homosporous b) Heterosporous c) Eusporangiate d) Leptosporangiate Answer: b) Heterosporous Explanation: Heterospory led to the evolution of the seed habit by providing protection and nutrition to the developing embryo. 122. _________the following is not a heterosporous pteridophyte? a) Selaginella b) Marsilea c) Isoetes d) Adiantum Answer: d) Adiantum Explanation: Adiantum is a homosporous fern, meaning it produces only one type of spore. 123. The retention of the megaspore within the megasporangium is an important step in the evolution of __________. a) Heterospory b) Seed habit c) Homospory d) Apogamy Answer: b) Seed habit Explanation: Retention of the megaspore ensures protection and nourishment of the developing embryo, leading to seed evolution. 124. Features is common between heterosporous pteridophytes and seed plants; a) Independent gametophyte b) Water-dependent fertilization c) Retention of the megaspore within the megasporangium d) External spore germination Answer: c) Retention of the megaspore within the megasporangium Explanation: In both heterosporous pteridophytes and seed plants, the megaspore remains enclosed, allowing protection and nourishment of the embryo. 125. The megaspore develops inside the megasporangium to form the __________. a) Sporophyte b) Male gametophyte c) Female gametophyte d) Zygote Answer: c) Female gametophyte Explanation: The megaspore develops into a female gametophyte, which produces eggs in archegonia. 126. The transition from free-living gametophytes to dependent gametophytes in pteridophytes indicates the evolution of __________. a) Homospory b) Alternation of generations c) Seed habit d) Gametophyte dominance Answer: c) Seed habit Explanation: A dependent gametophyte within the megasporangium is a key step toward seed evolution in plants. 127. In which pteridophyte does the female gametophyte develop inside the megaspore wall? a) Selaginella b) Lycopodium c) Pteridium d) Adiantum Answer: a) Selaginella Explanation: Selaginella has endosporic gametophyte development, where the female gametophyte forms inside the megaspore. 128. Structures in pteridophytes is functionally similar to the seed coat in seed plants a) Indusium b) Sporocarp c) Megasporangium wall d) Prothallus Answer: c) Megasporangium wall Explanation: The megasporangium wall protects the megaspore, similar to how a seed coat protects the embryo in seed plants. 129. Characteristic of seed plants evolved first in heterosporous pteridophytes a) Pollen formation b) Ovule development c) Retention of megaspore d) Development of cotyledons Answer: c) Retention of megaspore Explanation: Retention of the megaspore within the megasporangium was the first step toward the evolution of the seed habit. 130. Which of the following is not a step in seed habit evolution? a) Heterospory b) Retention of the megaspore c) Independent gametophyte d) Formation of an embryo inside the megaspore Answer: c) Independent gametophyte Explanation: In the evolution of seed habit, the gametophyte became dependent on the sporophyte, rather than being independent. 131. The alternation between the sporophyte and gametophyte in pteridophytes is called __________. a) Apogamy b) Apospory c) Alternation of generation d) Parthenogenesis Answer: c) Alternation of generation Explanation: Pteridophytes exhibit alternation of generations, with distinct sporophytic (diploid) and gametophytic (haploid) phases. 132. The dominant phase in the life cycle of pteridophytes is the __________. a) Gametophyte b) Sporophyte c) Zygote d) Spore Answer: b) Sporophyte Explanation: Unlike bryophytes, where the gametophyte is dominant, pteridophytes have a dominant sporophytic phase. 133. The process by which a sporophyte develops directly from a gametophyte without fertilization is called __________. a) Apospory b) Apogamy c) Parthenogenesis d) Amphimixis Answer: b) Apogamy Explanation: Apogamy is the formation of a sporophyte without fertilization, meaning no zygote is formed. 134. The formation of a gametophyte directly from sporophytic cells without meiosis is known as __________. a) Apogamy b) Apospory c) Homospory d) Heterospory Answer: b) Apospory Explanation: Apospory occurs when a gametophyte arises from somatic (diploid) sporophytic cells without undergoing meiosis. 135. Apogamy results in the formation of a __________ sporophyte. a) Haploid b) Diploid c) Polyploid d) Triploid Answer: a) Haploid Explanation: Since apogamy bypasses fertilization, the resulting sporophyte is haploid instead of diploid. 136. Apospory results in the formation of a __________ gametophyte. a) Haploid b) Diploid c) Triploid d) Polyploid Answer: b) Diploid Explanation: In apospory, the gametophyte forms from diploid sporophytic cells without meiosis, resulting in a diploid gametophyte. 137. Processes leads to an alternation of generations; a) Mitosis b) Meiosis c) Apogamy d) Apospory Answer: b) Meiosis Explanation: Meiosis in sporangia produces haploid spores, initiating the gametophytic phase and leading to alternation of generations. 138. In ferns, alternation of generations is __________. a) Haplontic b) Diplontic c) Haplo-diplontic d) None of the above Answer: c) Haplo-diplontic Explanation: Ferns have a haplo-diplontic life cycle, meaning they exhibit both haploid gametophyte and diploid sporophyte phases. 139. The gametophyte in pteridophytes is usually __________. a) Independent b) Dependent c) Absent d) Triploid Answer: a) Independent Explanation: In most pteridophytes, the gametophyte is free-living and independent but short-lived compared to the sporophyte. 140. The following statements is true about apospory a) It produces haploid gametophytes b) It is caused by meiosis c) It produces diploid gametophytes d) It leads to the formation of a zygote Answer: c) It produces diploid gametophytes Explanation: Apospory results in a diploid gametophyte because it arises from somatic cells without meiosis. 141. Causes of apogamy and apospory in ferns; a) Hormonal imbalance b) High temperature c) Nutrient deficiency d) All of the above Answer: d) All of the above Explanation: Apogamy and apospory can be induced by factors like hormonal imbalances, environmental stress, and nutrient deficiencies. 142. The following statements is true about apogamy; a) It leads to the formation of a diploid sporophyte b) It involves fertilization c) It leads to a haploid sporophyte d) It occurs through meiosis Answer: c) It leads to a haploid sporophyte Explanation: Since apogamy bypasses fertilization, the resulting sporophyte remains haploid. 143. Apogamy and apospory are examples of __________. a) Normal reproduction b) Deviations from alternation of generations c) Gametophyte formation d) Spore production Answer: b) Deviations from alternation of generations Explanation: Apogamy and apospory are abnormal reproductive processes that bypass normal alternation of generations. 144. An example of a fern that exhibits apospory; a) Dryopteris b) Lycopodium c) Selaginella d) Isoetes Answer: a) Dryopteris Explanation: Dryopteris has been observed to show apospory, where its gametophytes develop without spore formation. 145. The following conditions favors apospory in ferns; a) Low humidity b) High nutrient availability c) Excessive moisture d) Drought stress Answer: b) High nutrient availability Explanation: Apospory is often triggered by high nutrient availability, allowing the direct development of gametophytes from sporophytic tissues. 146. Parthenogenesis in pteridophytes refers to the development of an embryo from __________ without fertilization. a) Antheridium b) Archegonium c) Egg cell d) Spore Answer: c) Egg cell Explanation: Parthenogenesis is the process where an egg cell develops into an embryo without fertilization, leading to a new sporophyte. 147. Parthenogenesis results in the formation of a __________ sporophyte. a) Haploid b) Diploid c) Triploid d) Tetraploid Answer: a) Haploid Explanation: Since no fertilization occurs, the resulting sporophyte remains haploid (n) instead of diploid (2n). 148. Which of the following conditions can induce parthenogenesis in pteridophytes? a) High temperature b) Nutrient deficiency c) Lack of sperm cells d) All of the above Answer: d) All of the above Explanation: Parthenogenesis can be induced by various stress factors such as high temperature, nutrient deficiency, or lack of sperm cells. 149. In pteridophytes, parthenogenesis occurs in which structure? a) Antheridium b) Archegonium c) Rhizoid d) Sporangium Answer: b) Archegonium Explanation: Parthenogenesis takes place in the archegonium, where the egg cell develops into an embryo without fertilization. 150. Which type of parthenogenesis occurs in ferns? a) Sexual b) Asexual c) Vegetative d) All of the above Answer: b) Asexual Explanation: Parthenogenesis is a form of asexual reproduction since it does not involve fertilization. 151. Which of the following pteridophytes is known to exhibit parthenogenesis? a) Pteris b) Lycopodium c) Selaginella d) Equisetum Answer: a) Pteris Explanation: Some species of Pteris show parthenogenetic development, where the egg forms a sporophyte without fertilization. 152. In which phase of the pteridophyte life cycle does parthenogenesis occur? a) Gametophyte b) Sporophyte c) Both gametophyte and sporophyte d) None of the above Answer: a) Gametophyte Explanation: Parthenogenesis occurs in the gametophytic phase, where the haploid egg cell forms a sporophyte without fertilization. 153. Parthenogenesis in pteridophytes is similar to which process in seed plants? a) Apogamy b) Apomixis c) Double fertilization d) Polyembryony Answer: b) Apomixis Explanation: Apomixis in seed plants and parthenogenesis in pteridophytes both involve embryo development without fertilization. 154. Which of the following statements about parthenogenesis is false? a) It leads to genetic variation b) It occurs without fertilization c) It produces haploid sporophytes d) It is a form of asexual reproduction Answer: a) It leads to genetic variation Explanation: Since parthenogenesis does not involve fertilization, there is no genetic variation—the offspring are genetically identical to the parent. 155. In pteridophytes, the term "facultative parthenogenesis" means that parthenogenesis occurs __________. a) Under normal conditions b) Only under stressful conditions c) Due to mutations d) Only in primitive species Answer: b) Only under stressful conditions Explanation: Facultative parthenogenesis occurs only when normal fertilization is not possible, such as when sperm cells are absent. 156. The first scientist to study parthenogenesis in ferns was __________. a) Hofmeister b) Strassburger c) Darwin d) Linnaeus Answer: b) Strassburger Explanation: Strassburger was one of the first scientists to study parthenogenesis in ferns. 157. Which of the following environmental factors can suppress parthenogenesis? a) Abundant water b) Availability of sperm c) High nutrient supply d) All of the above Answer: d) All of the above Explanation: When normal fertilization conditions are available (water, sperm, nutrients), parthenogenesis is suppressed. 158. What is the difference between apogamy and parthenogenesis? a) Apogamy involves sporophyte development without gamete formation, while parthenogenesis involves egg cell development without fertilization b) Apogamy is sexual reproduction, parthenogenesis is asexual c) Apogamy occurs in animals, parthenogenesis in plants d) There is no difference Answer: a) Apogamy involves sporophyte development without gamete formation, while parthenogenesis involves egg cell development without fertilization Explanation: Apogamy is the development of a sporophyte without gamete formation, while parthenogenesis involves egg development without fertilization. 159. Which of the following is an evolutionary advantage of parthenogenesis? a) Ensures reproduction in the absence of sperm b) Increases genetic variation c) Leads to more complex sporophytes d) Requires double fertilization Answer: a) Ensures reproduction in the absence of sperm Explanation: Parthenogenesis helps a species reproduce even when sperm is absent, ensuring survival in unfavorable conditions. 160. The sporophyte produced through parthenogenesis in pteridophytes is __________. a) Fertile b) Sterile c) Always polyploid d) None of the above Answer: b) Sterile Explanation: Since parthenogenetic sporophytes are haploid, they are often sterile and unable to complete meiosis properly.