Maharashtra Board Class 11 Biology Chapter 3 Kingdom Plantae Solutions

11th Biology Chapter 3 Exercise Kingdom Plantae Solutions Maharashtra Board

Kingdom Plantae Class 11 Exercise Question Answers Solutions Maharashtra Board

Class 11 Biology Chapter 3 Exercise Solutions Maharashtra Board

Biology Class 11 Chapter 3 Exercise Solutions

1. Choose the correct option.

Question (A)Which is the dominant phase in Pteridophytes?
(a) Capsule
(b) Gametophyte
(c) Sporophyte
(d) Embryo
Answer: (c) Sporophyte
In simple words: The sporophyte generation is the most prominent and long-lived phase in the life cycle of Pteridophytes, performing most of the plant's functions.

🎯 Exam Tip: Understanding the dominant life cycle phases is crucial for distinguishing between major plant groups in examinations.

Question (B)The tallest living gymnosperm among the following is
(a) Sequoia sempervirens
(b) Taxodium mucronatum
(c) Zamia pygmaea
(d) Ginkgo biloba
Answer: (a) Sequoia sempervirens
In simple words: Sequoia sempervirens, commonly known as the California redwood, holds the record for being the tallest living tree species and is a type of gymnosperm.

🎯 Exam Tip: Remembering specific examples for biological superlatives like 'tallest' helps in both objective and descriptive questions.

Question (C)In Bryophytes
(a) sporophyte and gametophyte generation are independent
(b) sporophyte is partially dependent upon gametophyte
(c) gametophyte is dependent upon sporophyte
(d) inconspicuous gametophyte
Answer: (b) sporophyte is partially dependent upon gametophyte
In simple words: In Bryophytes, the sporophyte grows attached to and is nourished by the more dominant gametophyte, making it partially dependent.

🎯 Exam Tip: The interdependency between sporophyte and gametophyte is a key distinguishing feature of Bryophytes; focus on this relationship.

Question (D)A characteristic of Angiosperm is
(a) Collateral vascular bundles
(b) Radial vascular bundles
(c) Seed formation
(d) Double fertilization
Answer: (d) Double fertilization
In simple words: Double fertilization is a unique process in Angiosperms where two male gametes fertilize two different structures in the ovule, leading to the formation of both the embryo and endosperm.

🎯 Exam Tip: Double fertilization is a defining feature of angiosperms; understanding its steps and products is vital for exams.

Question (E)Angiosperms differ from gymnosperms in having
(a) Vessels in wood
(b) Mode of nutrition
(c) Siphonogamy
(d) Enclosed seed
Answer: Both (a) Monocotyledons and (d) Enclosed seed
In simple words: Angiosperms are characterized by the presence of vessels in their wood for efficient water transport and having seeds enclosed within fruits, distinguishing them from gymnosperms.

🎯 Exam Tip: When comparing plant groups, focus on unique structural and reproductive adaptations, as these are frequently tested differentiating points.

Question 2.How you place the pea, jowar and fern at its proper systematic position? Draw a flow chart.
Answer:
ℹ️ चित्र व्याख्या (Diagram Explanation): यह आरेख मटर, ज्वार और फर्न के वर्गीकरण को दर्शाता है। मटर और ज्वार दोनों किंगडम प्लांटे, सब-किंगडम फ़ैनरोगैमे और डिवीज़न एंजियोस्पर्मे से संबंधित हैं, लेकिन मटर डाइकोटिलिडोनी वर्ग में आता है, जबकि ज्वार मोनोकोटिलिडोनी वर्ग में आता है। फर्न किंगडम प्लांटे, सब-किंगडम क्रिप्टोगैमे और डिवीज़न टेरिडोफाइटा में आता है, जिसके बाद वर्ग टेरोप्सिडा है। यह विभिन्न पौधों के समूहों के पदानुक्रमित वर्गीकरण को स्पष्ट रूप से दर्शाता है।
In simple words: Pea is a dicotyledonous angiosperm, Jowar is a monocotyledonous angiosperm, and Fern is a pteridophyte cryptogam, each placed systematically based on their botanical characteristics.

🎯 Exam Tip: Flow charts illustrate systematic positions clearly; ensure you can accurately list the hierarchy (Kingdom, Sub-kingdom, Division, Class) for key plant examples.

Question 3.Complete the following table.

🎯 Exam Tip: Tables are an effective way to organize and recall comparative information; pay attention to unique characteristics for each group.

Question 4.Differentiate between Dicotyledonae and Monocotyledonae based on the following characters:
a. Type of roots
b. Venation in the leaves
c. Symmetry of flower
Answer:

🎯 Exam Tip: Mastering these fundamental differences between dicots and monocots is essential, as they are frequently used for identification and classification questions.

5. Answer the following questions.

Question (A)We observe that land becomes barren soon after monsoon. But in the next monsoon it flourishes again with varieties we observed in season earlier. How you think it takes place?
Answer:
1. After monsoon, plants like mosses (bryophytes), ferns (pteridophytes), small herbaceous plants, etc become dry, due to which land becomes barren.
2. However, spores of bryophytes, pteridophytes and seeds of herbaceous plants, grass remain in barren land.
3. During next monsoon, these spores and seeds germinate due to availability of water and other favourable conditions.
4. Bryophytes and pteridophytes require water for reproduction. Hence they flourish during monsoon season.
5. Along with bryophytes and pteridophytes varieties of higher plants like grasses, some seasonal herbs or shrubs grow on barren land during monsoon due to favourable conditions.
In simple words: After a dry spell, spores and seeds of various plants, especially those needing water for reproduction like bryophytes and pteridophytes, germinate with the onset of monsoon, leading to the land flourishing with diverse plant life again.

🎯 Exam Tip: This question assesses understanding of plant reproduction strategies and their adaptation to seasonal environmental changes, particularly the role of spores and seeds.

Question (B)Fern is a vascular plant. Yet it is not considered a Phanerogams. Why?
Answer:
1. Fern belongs to sub-kingdom Cryptogamae.
2. Cryptogams produce spores but do not produce seeds.
3. Also, in cryptogams the sex organs are concealed.
4. Phanerogams are seed producing plants and their sex organs are visible.
5. Hence, fern is a vascular plant. Yet it is not considered a Phanerogams.
In simple words: Despite having vascular tissue, ferns are classified as Cryptogams, not Phanerogams, because they reproduce by spores and have concealed reproductive organs instead of producing seeds.

🎯 Exam Tip: Differentiating between cryptogams (spore-producing, concealed organs) and phanerogams (seed-producing, visible organs) is a core concept in plant classification.

Question (C)Chlamydomonas is microscopic whereas Sargassum is macroscopic; both are algae. Which characters of these plants includes them in one group?
Answer:
1. Both Chlamydomonas and Sargassum belong to division Thallophyta.
2. Members of Thallophyta range from unicellular (e.g. Chlamydomonas) to multicellular (e.g. Sargassum).
3. Both are aquatic plants containing photosynthetic pigments.
4. In both Chlamydomonas and Sargassum plant body is not differentiated into root, stem and leaves.
5. The stored food is mainly in the form of starch and its other forms.
6. Cell wall is made up of cellulose and other components. Due to these characters, both Chlamydomonas and Sargassum are included in one group i.e. Thallophyta.
In simple words: Despite their size difference, Chlamydomonas and Sargassum are grouped as algae within Thallophyta because they both have undifferentiated plant bodies, are aquatic, perform photosynthesis, and share similar cell wall and stored food characteristics.

🎯 Exam Tip: Focus on fundamental biological criteria like body differentiation, habitat, and reproductive strategies for grouping diverse organisms, rather than just size.

Question 6.Girth of a maize plant does not increase over a period of time. Justify.
Answer:
1. Maize plant belongs to class monocotyledonae.
2. In monocotyledonous plants, vascular bundles are closed type.
3. Thus, cambium is absent between xylem and phloem, due to which secondary growth does not occur in these plants.
4. Increase in girth of a stem occurs by secondary growth. Thus, girth of a maize plant does not increase over a period of time.
In simple words: Maize is a monocot plant with closed vascular bundles lacking cambium, which prevents secondary growth responsible for an increase in stem girth, unlike dicot plants.

🎯 Exam Tip: Understanding the presence or absence of cambium and its role in secondary growth is critical for explaining differences in stem thickening between monocots and dicots.

Question 7.Radha observed a plant in rainy season on the compound wall of her school. The plant did not have true roots but root like structures were present. Vascular tissue was absent. To which group the plant may belong?
Answer:The plant observed by Radha belongs may belong to division Bryophyta, as it shows root like structures i.e. rhizoids and absence of vascular tissue.
In simple words: The plant likely belongs to Bryophyta, as evidenced by its lack of true roots, presence of rhizoids, and absence of vascular tissue, common characteristics of mosses and liverworts often found in moist environments.

🎯 Exam Tip: Key features like the presence of rhizoids (not true roots) and lack of vascular tissue are diagnostic for identifying Bryophytes in plant classification questions.

8. Draw neat labelled diagrams

Question 1.Draw neat and labelled diagram of:
(A) Spirogyra
(B) Chlamydomonas
Answer:
ℹ️ चित्र व्याख्या (Diagram Explanation): पहला चित्र स्पाइरोगाइरा (Spirogyra) की कोशिका संरचना को दर्शाता है, जिसमें म्यूसिलेज, कोशिका भित्ति, कोशिका झिल्ली, कोशिकाद्रव्य, केंद्रक, पाइरेनॉइड, क्लोरोप्लास्ट और तंतु शामिल हैं। दूसरा चित्र क्लेमाइडोमोनास (Chlamydomonas) की संरचना को दर्शाता है, जिसमें क्लोरोप्लास्ट, केंद्रक, पाइरेनॉइड (स्टार्च भंडारण) और माइटोकॉन्ड्रिया (अमीनो एसिड संश्लेषण) शामिल हैं, जो एक एकल-कोशिका वाले शैवाल को दिखाते हैं।
In simple words: The first diagram illustrates the cellular structure of Spirogyra, a filamentous algae, showing its mucilage, cell wall, chloroplast, nucleus, and pyrenoid. The second diagram shows Chlamydomonas, a unicellular algae, highlighting its chloroplast, nucleus, pyrenoid, and mitochondria.

🎯 Exam Tip: When drawing diagrams, ensure all key parts are clearly labeled and proportionate; accurate representation of cellular components is crucial for scoring.

Question (C)Draw neat and labelled diagram of Funaria.
Answer:
ℹ️ चित्र व्याख्या (Diagram Explanation): यह चित्र फ्यूनेरिया (Funaria) के जीवन चक्र के एक चरण को दर्शाता है, जिसमें मुख्य अक्ष पर उगने वाला गैमीटोफाइट और उस पर निर्भर स्पोरोफाइट शामिल है। स्पोरोफाइट में फुट, सेटा और कैप्सूल होता है, जबकि गैमीटोफाइट में मुख्य अक्ष और राइजॉइड्स शामिल होते हैं। यह ब्रायोफाइट की एक विशिष्ट संरचना को दर्शाता है, जहाँ स्पोरोफाइट गैमीटोफाइट से पोषण प्राप्त करता है।
In simple words: The diagram displays the Funaria plant, a bryophyte, clearly showing the dominant gametophyte stage with its main axis and rhizoids, and the dependent sporophyte attached, comprising the foot, seta, and capsule.

🎯 Exam Tip: For diagrams of bryophytes like Funaria, correctly labeling the gametophyte and dependent sporophyte, along with their respective parts, is essential for a complete answer.

Question (D)Draw neat and labelled diagram of Nephrolepis.
Answer:
ℹ️ चित्र व्याख्या (Diagram Explanation): यह चित्र नेफ्रोलेपिस (Nephrolepis) नामक फर्न को दर्शाता है, जिसमें उसके विभिन्न भागों जैसे ब्लेड, फ्रोंड, राइज़ोम और जड़ें दिखाई गई हैं। फ्रोंड, जो फर्न की पत्ती होती है, राइज़ोम से निकलती है और इसमें ब्लेड (क्लोरोफिल युक्त मुख्य भाग) और पेटीओल (डंठल) होता है। राइज़ोम भूमिगत तना होता है जहाँ से जड़ें निकलती हैं। यह एक सामान्य फर्न की संपूर्ण शारीरिक संरचना का प्रतिनिधित्व करता है। [Note: Frond: Fern leaf, originating from rhizome. It consists of blade and petiole, Blade: Main part of the frond which is rich in chlorophyll]
In simple words: This diagram illustrates the Nephrolepis fern, highlighting its fronds (leaves with blade and petiole), rhizome (underground stem), and roots, which collectively form the plant's structure.

🎯 Exam Tip: When presenting fern diagrams, ensure clear labels for the frond, rhizome, and roots, as these are key anatomical features for Pteridophytes.

Question (E)Draw neat and labelled diagram of Haplontic and Haplo-diplontic life cycle.
Answer:
ℹ️ चित्र व्याख्या (Diagram Explanation): यह आरेख दो प्रमुख जीवन चक्रों- हैप्लॉन्टिक (Haplontic) और हैप्लो-डिप्लॉन्टिक (Haplo-diplontic) को दर्शाता है। हैप्लॉन्टिक चक्र में, अगुणित (n) एकल-कोशिका या बहुकोशिकीय जीव प्रमुख होता है जो समसूत्री विभाजन से युग्मक बनाता है; निषेचन के बाद, द्विगुणित युग्मनज (2n) अर्धसूत्री विभाजन से अगुणित बीजाणु बनाता है। हैप्लो-डिप्लॉन्टिक चक्र में, अगुणित (n) और द्विगुणित (2n) दोनों बहुकोशिकीय जीव होते हैं, जो क्रमशः युग्मक और बीजाणु पैदा करते हैं।
In simple words: The diagram illustrates the haplontic life cycle, dominated by a haploid organism that undergoes meiosis after zygote formation, and the haplo-diplontic life cycle, which involves distinct multicellular haploid and diploid phases alternating through mitosis.

🎯 Exam Tip: Clearly understanding the ploidy levels (n and 2n) and the stages where mitosis and meiosis occur is crucial for distinguishing between haplontic and haplo-diplontic life cycles.

Question 9.Identify the plant groups on the basis of following features:
A. Seed producing plants
B. Spore producing plants
C. Plant body undifferentiated into root, stem and leaves
D. Plant needs water for fertilization
E. First vascular plants
Answer:
1. Phanerogams (Angiospermae and Gymnospermae)
2. Cryptogams (Thallophyta, Bryophyta and Pteridophyta)
3. Thallophyta, Bryophyta
4. Thallophyta, Bryophyta, Pteridophyta
5. Pteridophytes
In simple words: This question tests the classification of plant groups based on key features like seed production, spore production, body differentiation, water requirement for fertilization, and the presence of the first vascular tissues.

🎯 Exam Tip: A strong grasp of the distinguishing characteristics of major plant divisions is essential for accurately identifying groups based on given features.

Practical/Project:

Question 1.Study the Nephrolepis plant in detail.
Answer:
1. Nephrolepis belongs to division pteridophyta.
2. They grow abundantly in cool, shady, moist places.
3. Roots are adventitious (fibrous) growing from the underground stem.
4. Leaves are well developed on the stem (Rhizome).
5. They show presence of well-developed conducting system for transportation of water and food.
6. They reproduce asexually by spores produced within sporangia, which are present in sori. These sori are located along the posterior surface of leaflets.
7. These plants have neither fruits nor flowers.
8. Some ferms are used as food, medicine or as ornamental plants.
In simple words: Nephrolepis, a pteridophyte, thrives in moist, shady areas, featuring adventitious roots, well-developed leaves on a rhizome, a conducting system, and asexual reproduction via spores in sori, lacking fruits and flowers.

🎯 Exam Tip: When describing a plant in detail, always include its classification, habitat, key morphological features (roots, stem, leaves), reproductive method, and any unique characteristics.

Question 2.Study the coralloid roots, scale leaf and megasporophyll of Cycas in detail.
Answer:
1. Coralloid roots of Cycas: Coralloid roots of Cycas show association with blue green algae for nitrogen fixation. Coralloid roots are coral-like, dichotomously branched and fleshy. They grow upward toward the surface of the soil. These roots arise from the lateral branches of normal roots.
2. Scale leaf of Cycas: In Cycas leaves are dimorphic i.e. foliage leaves and scale leaves. Scale leaves are minute, membranous and brown. These are non- photosynthetic and provide protection to the stem apex.
3. Megasporophyll of Cycas: Megasporophylls are usually arranged in compact structures called female cones or female strobili. Megasporophyll contains megasporangia (ovule) which produce megaspores. [Students are expected to collect more information about coralloid roots, scale leaf and megasporophyll of Cycas.]
In simple words: Cycas features specialized coralloid roots that fix nitrogen with blue-green algae, dimorphic leaves including protective scale leaves, and megasporophylls arranged in cones to produce megaspores.

🎯 Exam Tip: For detailed studies of specific plant parts, always cover their structure, function, and any unique symbiotic relationships or adaptations.

Question 10.Observe the following diagram. Correct it and write the information in your words.
ℹ️ चित्र व्याख्या (Diagram Explanation): यह आरेख एक गलत जीवन चक्र को दर्शाता है जिसे सही किया जाना है। इसमें स्पोरोफाइट (2n), युग्मक (1n), अर्धसूत्री विभाजन, गैमीटोफाइट चरण, निषेचन, स्पोरोफाइट चरण, युग्मनज (2n) और बीजाणु (1n) जैसे विभिन्न चरण और संरचनाएं शामिल हैं। यह एक सामान्य पादप जीवन चक्र के घटकों को दर्शाता है, जिसमें द्विगुणित (sporophytic) और अगुणित (gametophytic) पीढ़ियों का प्रत्यावर्तन होता है।
Answer:
ℹ️ चित्र व्याख्या (Diagram Explanation): यह आरेख पादप जीवन चक्र में पीढ़ियों के सही प्रत्यावर्तन को दर्शाता है। यह दर्शाता है कि द्विगुणित (2n) स्पोरोफाइट अर्धसूत्री विभाजन से अगुणित (1n) बीजाणु बनाता है, जो गैमीटोफाइट (1n) में विकसित होता है। गैमीटोफाइट समसूत्री विभाजन से युग्मक (1n) बनाता है। युग्मकों के निषेचन से द्विगुणित युग्मनज (2n) बनता है, जो समसूत्री विभाजन से स्पोरोफाइट (2n) में विकसित होता है, जिससे चक्र पूरा होता है।
1. The given figure indicates alternation of generation.
2. The life cycle of a plant includes two generations, sporophytic (diploid = 2n) and gametophytic (haploid = n)
3. Some special diploid cells of sporophyte divide by meiosis to produce haploid cells.
4. These haploid cells divide mitotically to produce gametophyte.
5. On maturation, gametophyte produces male and female gametes which fuse during fertilization and produce diploid zygote.
6. Diploid zygote divides by mitosis and forms diploid sporophyte.
In simple words: The corrected diagram illustrates the alternation of generations in plants, where a diploid sporophyte undergoes meiosis to produce haploid spores, which grow into a haploid gametophyte; the gametophyte then produces gametes that fuse via fertilization to form a diploid zygote, developing into a new sporophyte.

🎯 Exam Tip: Accurately drawing and explaining the alternation of generations, including the ploidy of each stage and where meiosis and mitosis occur, is a high-scoring topic in plant biology.

11th Biology Digest Chapter 3 Kingdom Plantae Intext Questions and Answers

Can you recall? (Textbook Page No. 19)

Question.Why do we call plants as producers on land?
Answer:Plants can prepare their own food by the process of photosynthesis. Hence, they are called as producers on land.
In simple words: Plants are called producers because they can synthesize their own food using sunlight through photosynthesis, forming the base of most food chains.

🎯 Exam Tip: This foundational concept of photosynthesis as the primary energy source in ecosystems is fundamental; ensure you can define producers and their role clearly.

Can you recall? (Textbook Page No. 19)

Question.What are differences between sub-kingdoms cryptogamae and Phanerogamae?
Answer:

🎯 Exam Tip: Focus on the presence/absence of flowers, seeds, and the visibility of reproductive organs as key differentiators between Cryptogams and Phanerogams.

Observe and Discuss (Textbook Page No. 19)

Question.Collect different water samples of fresh water. Mount them on a glass slide and observe under a compound microscope. Try to identify the organisms which are visible under it.
Answer:Micro-organisms like Paramoecium, Amoeba, blue-green algae, unicellular algae, filamentous algae can be observed under compound microscope. [Students are expected to observe different water samples of fresh water under compound microscope and identify the organisms.]
In simple words: Observing freshwater samples under a microscope reveals diverse microorganisms such as Paramoecium, Amoeba, and various types of algae, including blue-green, unicellular, and filamentous forms.

🎯 Exam Tip: Practical observation skills are valued; be familiar with common freshwater microorganisms and their basic identification features under a microscope.

Can you tell? (Textbook Page No. 21)

Question.Give salient features of algae.
Answer:Algae belongs to division Thallophyta. Salient features of algae:
1. Habitat: Algae are mostly aquatic, few grow on other plants as epiphytes and some grow symbiotically. Some algae are epizoic i.e. growing or living non-parasitically on the exterior of living organisms. Aquatic algae grow in marine or fresh water. Most of them are free-living while some are symbiotic.
2. Structure: Plant body is thalloid i.e. undifferentiated into root, stem and leaves. They may be small, unicellular, microscopic like Cblorella (non-motile), Chlamydomonas (motile). They can be multicellular, unbranched, filamentous like Spirogyra or branched and filamentous like Chara. Sargassum is a huge macroscopic sea weed which measures more than 60 meters in length.
3. Cell wall: The algal cell wall contains either polysaccharides like cellulose - glucose or a variety of proteins or both. Reserve food material: Reserve food is in the form of starch and its other forms.
4. Photosynthetic pigments: Photosynthetic pigments like chlorophyll - a, chlorophyll - b, chlorophyll - c, chlorophyll - d, carotenes, xanthophylls, phycobilins are found in algae.
5. Reproduction: Reproduction takes place by vegetative, asexual and sexual method.
6. Life cycle: The life cycle shows phenomenon of alternation of generation, dominant haploid and reduced diploid phases.
In simple words: Algae are simple, mostly aquatic thallophytes with undifferentiated bodies, chlorophyll and accessory pigments for photosynthesis, and reproduce vegetatively, asexually, or sexually, often showing alternation of generations.

🎯 Exam Tip: When listing features, categorize them (habitat, structure, pigments, reproduction) for clarity and completeness, and remember key terms like 'thalloid body'.

Internet my friend (Textbook Page No. 20)

Question.Write different pigments found in algae.
Answer:Various types of photosynthetic pigments are found in algae.
1. Chlorophyll-a (Essential photosynthetic pigment) is present in all groups of algae.
2. The accessory pigments are chlorophyll-b, chlorophyll-c, chlorophyll-d, carotenes, xanthophylls and phycobilins. Phycobilins are of two types, i.e. phycocyanin and phycoerythrin. [Students are expected to collect more information about pigments found in algae from internet.]
In simple words: Algae possess chlorophyll-a as their primary photosynthetic pigment, supplemented by accessory pigments like chlorophyll-b, -c, -d, carotenes, xanthophylls, and phycobilins (phycocyanin and phycoerythrin), which give them their characteristic colors.

🎯 Exam Tip: Distinguish between primary (chlorophyll-a) and accessory pigments; knowing specific accessory pigments for different algal groups aids in classification questions.

Can you tell? (Textbook Page No. 21)

Question.Name the accessory pigments of algae.
Answer:The accessory pigments are chlorophyll-b, chlorophyll-c, chlorophyll-d, carotenes, xanthophylls and phycobilins. Phycobilins are of two types, i.e. phycocyanin and phycoerythrin. [Students are expected to collect more information about pigments found in algae from internet.]
In simple words: Algae use accessory pigments such as chlorophyll-b, chlorophyll-c, chlorophyll-d, carotenes, xanthophylls, and phycobilins (phycocyanin and phycoerythrin) to capture a broader spectrum of light for photosynthesis.

🎯 Exam Tip: Memorize the specific names of accessory pigments and their two main phycobilin types, as these are frequently asked in short answer questions.

Can you tell? (Textbook Page No. 21)

Question.Differentiate between Chlorophyceae and Phaeophyceae.
Answer:

🎯 Exam Tip: When differentiating, focus on pigments, stored food, and cell wall composition, and provide at least two distinct examples for each group for full marks.

Can you tell? (Textbook Page No.21)

Question.Enlist examples of Chlorophyceae and Rhodophvceae.
Answer:
1. Examples of Chlorophyceae: Chlorella, Chlamydomonas, Spirogyra, Chara, Volvox, Ulothrix, etc.
2. Examples of Rhodophyceae: Chondrus, Batrachospermum, Porphyra, Gelidium, Gracillaria, Polysiphonia, etc.
In simple words: Chlorophyceae includes green algae like Chlorella and Spirogyra, while Rhodophyceae includes red algae such as Porphyra and Gracillaria.

🎯 Exam Tip: Listing multiple examples for each algal class helps demonstrate broad knowledge and prepares you for diverse question formats.

Internet my friend (Textbook Page No. 21)

Question.Different forms of green, red, brown and blue green algae.
Answer:
1. Forms of green algae: Unicellular motile: e.g. Chlamydomonas Unicellular non-motile: E.g. Chlorella Colonial forms: e.g. Volvox Filamentous branched: e.g. Cladophora, Chara Filamentous unbranched: e.g. Ulothrix, Spirogyra
2. Forms of red algae: The red thalli of most of the red algae are multicellular, macroscopic, e.g. Gracilaria, Gelidium, Porphyra, Polysiphonia, etc. .
3. Forms of brown algae: Simple, branched and filamentous: Sargassum, Fucus, Ectocarpus Profusely branched: Laminaria, Dictyota, Kelps (Seaweed)
4. Forms of blue-green algae: Unicellular, colonial or filamentous, freshwater or marine water or terrestrial algae. [Note: Blue-green algae are cyanobacteria which are photosynthetic autotrophs.] [Students are expected to collect more information from internet.]
In simple words: Algae exhibit various forms, including unicellular (motile/non-motile), colonial, and filamentous (branched/unbranched) structures, and can be microscopic or macroscopic seaweeds, adapted to freshwater, marine, or terrestrial habitats.

🎯 Exam Tip: For each algal type, note down examples for unicellular, colonial, and filamentous forms; this variety is a common examination point.

Internet My Friend (Textbook Page No. 20)

Question. Enlist the forms of filamentous algae.
Answer: The forms of filamentous algae: 1. Filamentous branched: e.g. Cladophora, Chara, Ectocarpus, Dictyota, etc. 2. Filamentous unbranched: e.g. Ulothrix, Spirogyra, etc.In simple words: Filamentous algae can be branched (like Cladophora) or unbranched (like Spirogyra), referring to their thread-like growth patterns.

🎯 Exam Tip: Listing specific examples for each type of filamentous algae is crucial for full marks.

Internet My Friend (Textbook Page No. 21)

Question. Economic importance of algae.
Answer:(a) Many species of algae are used as food. For e.g. Chlorella (rich in cell proteins hence used as food supplement, even by space travelers), Sargassum, Laminaria, Porphyra, etc. (b) Alginic acid is produced commercially from Kelps. (c) Hydrocolloids like algin and carrageen are obtained from brown algae and red algae respectively. (d) 'Agar' which is used as solidifying agent in tissue culture is obtained from red algae like Gelidium and Gracilaria. (e) Brown algae like sea weeds are used a fodder for sheep, goat, etc. [Students are expected to collect more information about the economic importance of algae.] (f) Role of algae in environment.
Answer:(a) Being photosynthetic, algae help in increasing the level of dissolved oxygen in their immediate environment. (b) Algae are primary producers of energy rich compounds which forms the basis of food cycles in aquatic animals. [Students are expected to find out more information about the role of algae in environment on internet.]In simple words: Algae are vital for food, produce useful products like agar and alginic acid, and play a crucial role in ecosystems by producing oxygen and forming the base of aquatic food chains.

🎯 Exam Tip: Remember to categorize the economic importance (food, industrial products, fodder) and environmental roles (oxygen production, primary producers) for a comprehensive answer.

Can You Recall? (Textbook Page No. 19)

Question. Differentiate between Thallophytes and Bryophytes.
Answer:

🎯 Exam Tip: When differentiating, use clear, contrasting points for each characteristic to highlight the differences effectively.

Can You Tell? (Textbook Page No. 23)

Question. Why Bryophyta are called amphibians of Plant Kingdom?
Answer: Members of Bryophyta are mostly terrestrial plants which depend on water for fertilization and completion of their life cycle. Hence, they are called 'amphibians of Plant Kingdom'.In simple words: Bryophytes are called plant kingdom amphibians because they live on land but need water for reproduction, similar to how amphibians depend on water for part of their life cycle.

🎯 Exam Tip: The key phrase to remember is "dependence on water for fertilization" even though they are terrestrial.

Observe And Discuss (Textbook Page No. 21)

Question. You may have seen Funaria plant in rainy season. Why is it called amphibious plant?
Answer: Funaria belongs to division Bryophyta. It is a terrestrial plant but requires water for fertilization and completion of its life cycle. Hence, it is called as an amphibious plant.In simple words: Funaria, a bryophyte, is called amphibious because it lives on land but relies on water for its reproductive process, just like amphibians.

🎯 Exam Tip: Connect the definition of 'amphibious' directly to Funaria's requirement for water in reproduction to score well.

Observe And Discuss (Textbook Page No. 23)

Question. You may have seen the various plants which do not bear flowers, fruits and seeds but they have well developed root, stem and leaves. Discuss.
Answer:1. The plants which do not bear flowers, fruits and seeds, but have true roots, stem and leaves belong to division Pteridophyta. 2. These plants are cryptogams as they do not produce seeds and flowers. 3. They have primitive conducting system.In simple words: Plants with true roots, stems, and leaves but no flowers, fruits, or seeds belong to Pteridophyta; they are cryptogams with a basic vascular system.

🎯 Exam Tip: The presence of true roots, stem, and leaves combined with the absence of seeds and flowers are the defining characteristics to mention.

Can You Tell? (Textbook Page No. 23)

Question. Pteridophytes are also known as vascular Cryptogams - Justify.
Answer:1. The reproductive organs of pteridophytes are hidden. 2. Pteridophytes do not produce flowers, fruits and seeds. They reproduce asexually by forming spores and sexually by forming gametes, hence they belong to Cryptogamae. 3. These plants possess a primitive conducting system. Thus, conduction of water and food occurs through vascular tissue. Hence, Pteridophytes are also known as vascular Cryptogams.In simple words: Pteridophytes are "vascular cryptogams" because they have hidden reproductive organs (produce spores, no seeds/flowers), making them cryptogams, and they possess true vascular tissues for water and food transport.

🎯 Exam Tip: Clearly state both aspects - why they are 'cryptogams' (hidden reproduction via spores) and why they are 'vascular' (presence of conducting tissues).

Can You Tell? (Textbook Page No. 23)

Question. Give one example of aquatic and xerophytic Pteridophytes.
Answer: Habitat: Pteridophytes grow in moist and shady places, e.g. Ferns, Horsetail. Some are aquatic (Azolla, Marsilea), xerophytic (Equisetum) and epiphytic (Lycopodium).In simple words: Azolla and Marsilea are examples of aquatic pteridophytes, while Equisetum is a xerophytic pteridophyte.

🎯 Exam Tip: Ensure you provide one specific example for each category (aquatic and xerophytic) as requested.

Can You Recall? (Textbook Page No. 19)

Question. Give any two examples of Pteridophyta.
Answer: Nephrolepis, Selaginella, Azolla, Marsilea, Equisetum, Lycopodium, Psilotum, Dryopteris, Pteris, Adiantum.In simple words: Examples of Pteridophyta include ferns like Nephrolepis and Dryopteris, or club mosses like Lycopodium.

🎯 Exam Tip: Providing any two distinct names from the list is sufficient for the answer.

Can You Tell? (Textbook Page No. 25)

Question. Give general characters of Gymnosperms and Angiosperms.
Answer:1. General characters of Gymnosperms: (a) Types: Most of the gymnosperms are evergreen, shrubs or woody trees. (b) Vascular tissues: They are vascular plants having xylem with tracheids and phloem with sieve cells. (c) Flower: These are primitive group of flowering plants producing naked seeds. (d) Body: The plant body is sporophyte. It is differentiated into root, stem and leaves. (e) Roots: The root system is tap root type. In some gymnosperms, the roots form symbiotic association with other life forms. Coralloid roots of Cycas show association with blue green algae and roots of Pinus show association with endophytic fungi called mycorrhizae. (f) Stem: In gymnosperms, stem is mostly erect, aerial, solid and cylindrical. Secondary growth is seen in Gymnosperms due to the presence of cambium. In Cycas it is usually unbranched, while in conifers it is branched, (e.g. Pinus, Cedrus). (g) Leaves: The leaves are dimorphic. The foliage leaves are green, simple needle like or pinnately compound, whereas scale leaves are small, membranous and brown. (h) Spores: Spores are produced by microsporophyll (Male) and megasporophyll (Female). (ii) General characters of angiosperms: (a) Habitat: Angiosperms is a group of highly evolved plants, primarily adapted to terrestrial habitat. (b) Alternation of generations: Angiosperms show heteromorphic alternation of generation in which the sporophyte is diploid, dominant, autotrophic and independent. The gametophytes (male or female) are haploid, reduced and concealed. (c) Spores and Sporophylls: Angiosperms are heterosporous. Microspores (commonly called pollens) are formed in microsporangia (or anthers). They develop in highly specialized microsporophyll or stamens while megaspores are formed in megasporangia (or ovules) borne on highly specialized megasporophyll called carpel. (d) Flower: Besides the essential whorls of microsporophylls (androecium) and megasporophylls (gynoecium), there are accessory whorls namely, calyx (sepals) and corolla (petals) arranged together to form flowers.In simple words: Gymnosperms are evergreen plants with naked seeds, tracheids, and distinct sporophylls, while Angiosperms are highly evolved flowering plants with seeds enclosed in fruits, show clear alternation of generations, and have complex flowers with accessory whorls.

🎯 Exam Tip: For a comprehensive answer, ensure you cover key characteristics for both groups such as seed type, vascular tissue, stem/leaf structure, and reproductive parts.

Observe And Discuss (Textbook Page No. 23)

Question. Observe all garden plants like Cycas, Thuja, Pinus, Sunflower, Canna and compare them. Note similarities and dissimilarities among them.
Answer:1. When we observe garden plants like Cycas, Thuja, Pinus, Sunflower, Canna, following similarities can be observed: Plant body is divided into root, stem and leaves. 2. When we observe garden plants like Cycas, Thuja, Pinus, Sunflower, Canna, following dissimilarities can be observed: (a) In Cycas, Thuja and Pinus seeds are not enclosed within a fruit, whereas in Sunflower and Canna seeds are enclosed within a fruit. (b) Plants like Cycas, Thuja, Pinus show cones bearing microsporophylls and megasporophylls, whereas sunflower and Canna plant bear flowers. (c) In Cycas, Thuja and Pinus green, simple needle like or pinnately compound foliage leaves and brown, membranous scaly leaves can be observed, whereas in Sunflower, Canna green foliage leaves can be observed.In simple words: All these garden plants share the basic plant body differentiation into root, stem, and leaves. However, they differ in seed enclosure (naked in Cycas, Thuja, Pinus vs. enclosed in Sunflower, Canna), reproductive structures (cones vs. flowers), and leaf morphology.

🎯 Exam Tip: Clearly separate similarities from dissimilarities and provide specific contrasting examples for each difference (e.g., naked seeds vs. enclosed seeds, cones vs. flowers).

Can You Recall? (Textbook Page No. 24)

Question. What are the salient features of angiosperms?
Answer:(ii) General characters of angiosperms: (a) Habitat: Angiosperms is a group of highly evolved plants, primarily adapted to terrestrial habitat. (b) Alternation of generations: Angiosperms show heteromorphic alternation of generation in which the sporophyte is diploid, dominant, autotrophic and independent. The gametophytes (male or female) are haploid, reduced and concealed. (c) Spores and Sporophylls: Angiosperms are heterosporous. Microspores (commonly called pollens) are formed in microsporangia (or anthers). They develop in highly specialized microsporophyll or stamens while megaspores are formed in megasporangia (or ovules) borne on highly specialized megasporophyll called carpel. (d) Flower: Besides the essential whorls of microsporophylls (androecium) and megasporophylls (gynoecium), there are accessory whorls namely, calyx (sepals) and corolla (petals) arranged together to form flowers.In simple words: Angiosperms are highly evolved terrestrial plants characterized by dominant sporophytic generation, heterosporous reproduction with specialized microsporophylls (stamens) and megasporophylls (carpels), and the presence of complex flowers with both essential and accessory whorls.

🎯 Exam Tip: Focus on unique angiosperm features like being highly evolved, having flowers, and enclosed seeds (though not explicitly listed in this answer, it's a key feature often discussed). The question asks for "salient features" so ensure broad coverage.

Can You Recall? (Textbook Page No. 24)

Question. What is double fertilization?
Answer:(a) Double fertilization is a characteristic feature of angiosperms. (b) In this process one male gamete fuses with egg cell and another male gamete fuses with secondary nucleus, to form an embryo and endosperm respectively.In simple words: Double fertilization, unique to angiosperms, involves two fusion events: one male gamete fertilizes the egg to form an embryo, and another fuses with the central cell (secondary nucleus) to form the endosperm.

🎯 Exam Tip: Clearly explain both fusion events (egg + male gamete = embryo; secondary nucleus + male gamete = endosperm) as this is the core of double fertilization.

Can You Recall? (Textbook Page No. 24)

Question. Explain in brief the two classes of Angiosperms? Draw and label one example of each class.
Answer: Two classes of Angiosperms are Dicotyledonae and Monocotyledonae. a. Dicotyledonae: 1. These plants have two cotyledons in their embryo. 2. They have a tap root system and the stem is branched. 3. Leaves show reticulate venation. 4. Flowers show tetramerous or pentamerous symmetry. 5. Vascular bundles are conjoint, collateral and open type. 6. Cambium is present between xylem and phloem for secondary growth. 7. In dicots, secondary growth is commonly found. e. g. Helianthus annuus (Sunflower) b. Monocotyledonae: 1. These plants have single cotyledon in their embryo. 2. They have adventitious root system and stem is rarely branched. 3. Leaves generally have sheathing leaf base and parallel venation. 4. Flowers show trimerous symmetry. 5. The vascular bundles are conjoint, collateral and closed type. 6. Cambium is absent between xylem and phloem. 7. In Monocots, except few plants secondary growth is absent, e.g. Zea mays (Maize)In simple words: Angiosperms are divided into Dicots, which have two cotyledons, taproots, branched stems, reticulate venation, and open vascular bundles with cambium for secondary growth (e.g., Sunflower), and Monocots, which have one cotyledon, fibrous roots, usually unbranched stems, parallel venation, and closed vascular bundles without cambium, thus lacking extensive secondary growth (e.g., Maize).

🎯 Exam Tip: Focus on distinct differentiating features like cotyledon number, root system, venation, and presence/absence of cambium for secondary growth. Provide one clear example for each class. (Note: The drawing part is not rendered as per instructions, but the text description fulfills the example requirement).

Try This (Textbook Page No. 24)

Question. Study the leaves of Hibiscus, Peepal, Canna, Grass and Tulsi. Classify them as Monocot and Dicot.
Answer:

🎯 Exam Tip: The primary characteristic for classifying leaves as monocot or dicot is their venation pattern (parallel for monocots, reticulate for dicots).

Can You Tell? (Textbook Page No. 25)

(i) Question. Distinguish between Dicotyledonae and Monocotyledonae.
Answer: Spores and Sporophylls: Angiosperms are heterosporous. Microspores (commonly called pollens) are formed in microsporangia (or anthers). They develop in highly specialized microsporophyll or stamens while megaspores are formed in megasporangia (or ovules) borne on highly specialized megasporophyll called carpel.
(ii) Question. Why do Dicots show secondary growth while Monocots don't?
Answer:(a) In dicots, vascular bundles are conjoint, collateral and open type. Cambium is present between xylem and phloem for secondary growth. (b) Whereas in monocots, vascular bundles are conjoint, collateral and closed type. Thus, due to absence of cambium, secondary growth does not occur in majority of monocots.In simple words: Dicots exhibit secondary growth because they possess open vascular bundles with cambium, allowing for lateral expansion, while monocots generally lack cambium in their closed vascular bundles, hence they don't show significant secondary growth.

🎯 Exam Tip: The key difference lies in the presence or absence of cambium in the vascular bundles. Dicots have open bundles with cambium, enabling secondary growth, whereas monocots have closed bundles without cambium.

Observe And Discuss (Textbook Page No. 23)

Question. Which differences did you notice between Gymnosperms and Angiosperms?
Answer:

🎯 Exam Tip: Highlight key evolutionary advancements in angiosperms (e.g., enclosed seeds, vessels, sieve tubes with companion cells, double fertilization) as these are critical distinguishing factors.

Can You Tell? (Textbook Page No. 26)

Question. What is alternation of generations?
Answer: The sporophytic and gametophytic generations generally occur alternately in the life cycle of a plant. This phenomenon is called alternation of generations.In simple words: Alternation of generations is the life cycle pattern in plants where a diploid sporophyte generation alternates with a haploid gametophyte generation.

🎯 Exam Tip: Define both sporophytic (diploid) and gametophytic (haploid) generations and emphasize their alternating sequence in the life cycle.

Can You Tell? (Textbook Page No. 26)

Question. Which phase is dominant in the life cycle of Bryophyta and Pteridophyta?
Answer: In the life cycle of Bryophyta, gametophyte is the dominant phase whereas in the life cycle of Pteridophyta, sporophyte is the dominant phase.In simple words: In Bryophytes, the gametophyte (haploid, photosynthetic) is the dominant phase, while in Pteridophytes, the sporophyte (diploid, independent) is dominant.

🎯 Exam Tip: Clearly state the dominant phase for each group. Remember: Bryophytes - Gametophyte dominant; Pteridophytes - Sporophyte dominant.

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