Samacheer Kalvi Class 11 Bio Botany Solutions Chapter 2 Plant Kingdom

🎯 Exam Tip: Focus on fundamental characteristics like seed formation and the dominance of the sporophyte phase when identifying shared traits between gymnosperms and angiosperms.

Question 9. Do you think the shape of chloroplast is unique for algae? Justify your answer.
Answer: The shape of the chloroplast is not unique for algae because it varies widely among different species of algae. For instance, chloroplasts can be cup-shaped (e.g., in Chlamydomonas), reticulate (e.g., in Oedogonium), spiral (e.g., in Spirogyra), stellate (e.g., in Zygnema), or plate-like (e.g., in Mougeoutia). This variety in chloroplast structure helps algae adapt to different light conditions and metabolic needs.
In simple words: No, the shape of the chloroplast is not special only to algae because different types of algae have chloroplasts in many shapes, like cups, spirals, or stars.

🎯 Exam Tip: When asked to justify an answer about uniqueness, provide diverse examples to demonstrate the variability within the group in question.

Question 10. Do you agree with the statement that Bryophytes need water for fertilization? Justify your answer.
Answer: Yes, I agree that bryophytes need water for fertilization. Bryophytes are considered "amphibians of the plant kingdom" because they thrive in moist, shady environments. Water is essential for the male gametes (sperms) to swim and reach the female reproductive organs (archegonia) for fertilization. Without water, their life cycle cannot be completed. This dependence on water for reproduction limits bryophytes to specific habitats.
In simple words: Yes, bryophytes need water to fertilize. Their male cells must swim through water to reach the female cells so they can make new plants.

🎯 Exam Tip: Emphasize the mobility of male gametes and the role of water as a medium for their transfer as the primary justification.

Part-II

I. Choose the Correct Option.

Question 1. Gametophytic phase is ............ .
(a) triploid
(b) tetraploid
(c) haploid
(d) diploid
Answer: (c) haploid
In simple words: The gametophytic phase refers to the part of a plant's life cycle where cells have only one set of chromosomes. This is called being haploid, meaning they have half the usual number of chromosomes found in body cells.

🎯 Exam Tip: Remember that gametophytes produce gametes, which are always haploid, making the entire gametophytic phase haploid.

Question 2. The numbers of known species of Angiosperms in the world is
(a) 268600
(b) 286600
(c) 224400
(d) 274832
Answer: (a) 268600
In simple words: There are about 268,600 known kinds of flowering plants, which are called angiosperms. This large number shows how diverse and successful flowering plants are on Earth.

🎯 Exam Tip: For numerical data like species counts, it's helpful to remember the approximate figure rather than exact, specific digits for quick recall.

Question 3. Which algae leads an endozoic life in Hydra?
(a) Chlorella
(b) Gracilaria
(c) Ulothrix
(d) Chlamydomonas
Answer: (a) Chlorella
In simple words: Some tiny green algae, called Chlorella, can live inside other animals, like the small freshwater animal called Hydra. This is a special type of living arrangement where one lives inside another.

🎯 Exam Tip: Remember specific examples of symbiotic relationships, such as Chlorella living inside Hydra, as they are common exam questions.

Question 4. The protein bodies found in chromatophores & assist in the synthesis and storage of starch is
(a) Leucoplasts
(b) Floridean starch
(c) Pyrenoids
(d) Mannitol
Answer: (c) Pyrenoids
In simple words: Pyrenoids are small protein-rich parts found inside the chloroplasts of algae. They help in making and storing starch, which is how algae keep their food.

🎯 Exam Tip: Associate pyrenoids directly with starch synthesis and storage in algae, as this is their primary function.

Question 5. Postelia palmaeformis is commonly known as
(a) Sea kelp
(b) Sea shell
(c) Sea palm
(d) Sea worth
Answer: (c) Sea palm
In simple words: Postelia palmaeformis is a type of seaweed often called "sea palm" because it looks like a small palm tree. It has a stem-like part and fronds that resemble palm leaves.

🎯 Exam Tip: Learn the common names of important plant species, especially those with distinctive appearances, as they are frequently tested.

Question 6. In Chara, thallus is encrusted with ............ .
(a) calcium carbonate
(b) hydrogen sulphate
(c) silica
(d) ammonium carbonate
Answer: (a) calcium carbonate
In simple words: The body of the Chara plant, called a thallus, is often covered with a layer of calcium carbonate. This makes the plant feel rough or gritty, and it helps provide some structural support.

🎯 Exam Tip: Remember specific characteristics of key plant examples; for Chara, its calcium carbonate encrustation is a notable feature.

Question 7. Gemmae formation is not traced in which three of the given four options
(a) Marchantia
(b) Riella
(c) Ricciocarpus
(d) Anthoceros
(i) ab & c
(ii) be & d
(iii) ab & d
Answer: (ii) be & d
In simple words: Gemmae are small buds that help plants reproduce without seeds. While Marchantia makes gemmae, plants like Riella, Ricciocarpus, and Anthoceros usually do not form them.

🎯 Exam Tip: Focus on knowing which specific plant examples exhibit or do not exhibit particular reproductive methods like gemmae formation.

Question 8. Find out the aquatic bryophytes of the following.
(a) Riella
(b) Ricciocarpus
(c) Riccia
(d) Bryopteris
(i) a&c
(ii) b&c
(iii) c&d
(iv) a&b
Answer: (iv) a&b
In simple words: Aquatic bryophytes are a type of moss that lives in water. From the choices, Riella and Ricciocarpus are examples of bryophytes that can grow in water.

🎯 Exam Tip: Learn specific examples of aquatic forms within plant groups like bryophytes, as these are often used in identification questions.

Question 9. Aplanospores are thin-walled non-motile spores.
(a) Zoospores
(b) Akinetes
(c) Aplanospores
(d) Genunae
Answer: (c) Aplanospores
In simple words: Aplanospores are types of spores that are thin-walled and cannot move on their own. They are produced by some algae and fungi for reproduction.

🎯 Exam Tip: Differentiate between different types of spores based on their wall thickness and motility for accurate identification.

Question 10. Which one of the following is a terrestrial chlorophycea?
(a) Chlorella
(b) Zygnema
(c) Trentipohlia
(d) Ulva
Answer: (c) Trentipohlia
In simple words: Trentipohlia is a type of green alga that lives on land. Most algae live in water, but some, like Trentipohlia, have adapted to grow on moist surfaces on land.

🎯 Exam Tip: Note the exceptions to general rules, such as terrestrial algae, and remember specific examples like Trentipohlia.

Question 11. Thick walled spores meant for perrennation are known as
(a) Aplanospores
(b) Akinetes
(c) Endospores
(d) Zoospores
Answer: (b) Akinetes
In simple words: Akinetes are special cells that have thick walls and can survive bad conditions. They help some plants and algae last through times when it's too cold or dry, and then they can grow when conditions get better.

🎯 Exam Tip: Understand that akinetes are survival spores designed for unfavorable conditions, characterized by their thick walls and dormant state.

Question 12. The photosynthetic part of the Phaeophyceae thallus Is called as
(a) holdfast
(b) stipes
(c) lamina
(d) fronds
Answer: (d) fronds
In simple words: In brown algae (Phaeophyceae), the main body or thallus is often divided into parts. The flat, leaf-like parts that perform photosynthesis are called fronds.

🎯 Exam Tip: Familiarize yourself with the specialized terms for different parts of algal thalli, such as fronds for the photosynthetic blades of brown algae.

Question 13. The female sex organ of red algae is known as
(a) Archegonium
(b) Spermatogonium
(c) Carpogonium
(d) Oogonium
Answer: (c) Carpogonium
In simple words: In red algae, the female part that holds the egg cell is called a carpogonium. It's a special flask-shaped structure involved in their reproduction.

🎯 Exam Tip: Know the specific names of reproductive structures for different algal groups; carpogonium is characteristic of red algae.

Question 14. Endosperm is triploid and haploid in
(a) Pteridophyta & Gymnosperm
(b) Angiosperm & Gymnosperm
(c) Gymnosperm & monocot
(d) Gymnosperm & dicot
Answer: (b) Angiosperm & Gymnosperm
In simple words: The endosperm, which provides food for the embryo, is triploid (has three sets of chromosomes) in flowering plants (angiosperms) and haploid (has one set of chromosomes) in cone-bearing plants (gymnosperms). This difference shows a key feature of their seed development.

🎯 Exam Tip: Differentiate the ploidy level of endosperm in angiosperms (triploid, 3n) versus gymnosperms (haploid, n) as it's a critical distinction.

Question 15. Gelidium belongs to ............ members.
(a) Rhodophyccae
(b) Phaeophyceae
(c) Cyanophyceae
(d) Dinophyceae
Answer: (a) Rhodophyceae
In simple words: Gelidium is a type of red algae. It is commonly used to make agar, which is a jelly-like substance used in many applications, from food to science labs.

🎯 Exam Tip: Associate key genera with their respective algal classes, remembering Gelidium as a member of Rhodophyceae (red algae).

Question 16. ............ is known as leather leaf fern
(a) Marsilea
(b) Azolla
(c) Selaginella
(d) Rumohra adiantiformis
Answer: (d) Rumohra adiantiformis
In simple words: The fern known as Rumohra adiantiformis is often called the "leather leaf fern" because its fronds are tough and leathery. This makes it popular for use in flower arrangements.

🎯 Exam Tip: Learn the common names of important plant species, especially when they refer to a distinctive physical characteristic.

Question 17. Stele includes
(a) Xylem, phloem & cambium
(b) Xylem, phloem & medulla
(c) Xylem, phloem & pericycle
(d) Xylem, phloem, pericycle & medulla
Answer: (d) Xylem, phloem, pericycle & medulla
In simple words: The stele is the central part of a plant stem or root. It includes the vascular tissues (xylem for water, phloem for food), the tissue around them (pericycle), and sometimes a central core (medulla or pith). These parts work together to transport water and nutrients.

🎯 Exam Tip: Remember the components of the stele, which typically include vascular tissues and associated ground tissues like pericycle and medulla.

Question 18. Marchantia vegetatively propagates by ............ .
(a) tubers
(b) gemmae
(c) buds
(d) brood bodies
Answer: (b) gemmae
In simple words: Marchantia, a type of liverwort, reproduces asexually using small, disk-shaped structures called gemmae. These gemmae are formed in cups on the surface of the plant and can grow into new plants when dispersed.

🎯 Exam Tip: Focus on identifying specific vegetative propagation structures for different plant groups, such as gemmae in Marchantia.

Question 19. The organ in bryophytes that help to attach the thallus to the substratum is
(a) Hold fast
(b) Rhizoids
(c) Rhizopore
(d) Roots
Answer: (b) Rhizoids
In simple words: Bryophytes, like mosses and liverworts, use tiny, root-like structures called rhizoids to anchor themselves to the ground or other surfaces. These rhizoids mainly help them stick in place, not to absorb water and nutrients like true roots.

🎯 Exam Tip: Distinguish rhizoids from true roots; rhizoids primarily provide anchorage, while roots also absorb water and nutrients.

Question 20. Coralloid roots of cycas have a symbiotic association with ............ .
(a) Mycorrhiza
(b) Mycorrhiza
(c) Euglena
(d) Rhizobium
Answer: (a) Blue-green algae
In simple words: The special coralloid roots of Cycas plants live together with blue-green algae. This partnership helps the Cycas plant get nitrogen, which is important for its growth, as the algae can take nitrogen from the air.

🎯 Exam Tip: Recall the specific symbiotic partner for Cycas coralloid roots (blue-green algae) and the benefit it provides (nitrogen fixation).

II. Match the Following & Find the Correct Answer.

Question 1.
(i) Spores look similar to parental cell – Zoospore (A)
(ii) Thick walled aplanospores – Autospore (B)
(iii) Thin walled non-motile spores – Hypnospore (C)
(iv) Thin walled motile spores – Aplanospore (D)

🎯 Exam Tip: Carefully read each description and match it with the correct spore type, paying attention to details like wall thickness and motility.

Question 2.
(i) Helianthusannum – Amphiboloicstele (A)
(ii) Lycopodium serratum – Eustele(B)
(iii) Zeamays – Actinostele (C)
(iv) Adiantumpedatum – Atactostele (D)

🎯 Exam Tip: Memorize the specific stele types associated with different plant genera, as these correlations are frequently tested in plant anatomy.

Question 3.
(i) Fossil bryophyte – Lepidodendron, Williamson (A)
(ii) Fossil Algae – Calamites Baragwanthia (B)
(iii) Fossil pteridophyte – Naiadita, Hepaticites (C)
(iv) Fossil Gymnosperm – Palaeoporella, Dimorphosiphon (D)

🎯 Exam Tip: Create flashcards or a table to link fossil plant names with their respective plant groups (bryophyte, algae, pteridophyte, gymnosperm) for easier recall.

Question 4.
(i) Abies balsamea – Drug for cancer treatment (A)
(ii) Taxus brevifolia – Wood for making door, boat & railway sleepers (B)
(iii) Cedrus deodara – Treatment for asthma & bronchitis(C)
(iv) Ephedra gerardiana - Slide mounting medium(D)

🎯 Exam Tip: Focus on linking plant names with their specific economic or medicinal uses, paying attention to unique applications for each species.

Question 5. Find the chromosome number of the following by choosing the correct option.
(i) Embryo of bryophyta
(ii) Embryo of Angiosperm
(iii) Endosperm of Angiosperm
(iv) Sporophyte of pteridophyta

🎯 Exam Tip: Clearly remember the ploidy levels (n, 2n, 3n) of key structures like embryos and endosperm in different plant groups, as these are fundamental concepts.

III. Choose the Wrong Statement.

Question 1. The following statement is not applicable to which one of the following options: The sporophyte is dominant, photosynthetic, and independent. The gametophytic phase is represented by a single to few celled gametophyte
(a) Fucus
(b) Mango
(c) Pinus
(d) Marchantia
Answer: (d) Marchantia
In simple words: The statement describes plants where the sporophyte (the spore-producing stage) is the main, independent plant, and the gametophyte (the sex cell-producing stage) is very small. This is true for Fucus, Mango, and Pinus. However, Marchantia is a bryophyte where the gametophyte is the dominant and independent plant, so the statement does not apply to it.

🎯 Exam Tip: Understand the concept of dominant generation in different plant groups; bryophytes (like Marchantia) have a dominant gametophyte, while Fucus, Mango, and Pinus have a dominant sporophyte.

Question 2. One of the following is not a Marine Algae.
(a) Gracilaria
(b) Oedogonium
(c) Cladophora
(d) Sargassum
Answer: (c) Oedogonium
In simple words: Oedogonium is a type of green alga that usually lives in fresh water, like ponds and lakes. Gracilaria, Cladophora, and Sargassum are typically found in marine (saltwater) environments. So, Oedogonium is the one that is not a marine algae.

🎯 Exam Tip: Be familiar with common examples of algae and their preferred habitats (freshwater vs. marine) to easily identify the odd one out.

Question 5. Pollination is not entomophilous in
(a) Hibiscus
(b) Mangifera
(c) Missing option from source
(d) Cycas
Answer: (d) Cycas
In simple words: Cycas plants are not pollinated by insects. Instead, their pollen is carried by wind, which is called anemophily.

🎯 Exam Tip: Remember that entomophilous means insect pollination. Knowing the specific pollination methods for different plant groups helps in classification.

Question 6. The following one is not a monoecious plant
(a) Pinus
(b) Cycas
(c) Alnus
(d) Ginkgo
Answer: (b) Cycas
In simple words: Cycas plants are dioecious, meaning male and female reproductive parts grow on separate individual plants. Pinus, Alnus, and Ginkgo, however, are monoecious, having both male and female structures on the same plant.

🎯 Exam Tip: Understand the terms "monoecious" (both sexes on one plant) and "dioecious" (sexes on separate plants) for plant classification.

Question 7. Which one of the following is not the correct statement regarding Algae?
(a) The study of Algae is known as Phycology
(b) A wide range of thallus organization is found in Algae
(c) Algae are eukaryotic except Blue Green Algae
(d) They are the simplest plant group with root stem and leaves
Answer: (d) They are the simplest plant group with root stem and leaves
In simple words: Algae are simple plants that do not have true roots, stems, or leaves like more complex plants do. Blue-green algae are prokaryotic, which means they do not have a true nucleus, unlike other algae.

🎯 Exam Tip: Algae are often called thallophytes because their plant body is a simple thallus, lacking true roots, stems, and leaves.

IV. Find out the true or false statements from the following and on that basis find the correct answer.

Question 1.
(i) Chara thallus is encrusted with calcium carbonate
(ii) Siliceous wall occurs in the cell wall of Diatom
(iii) Soil inhabiting algae - Fritshchiella
(iv) Cladophora crispate is growing now

🎯 Exam Tip: Pay close attention to the specific characteristics of different algal groups, especially their cell wall composition and habitat.

Question 2.
(i) Prothallus develop into a sporophyte
(ii) Algae growing on snow is known as cryptophytes
(iii) The common name of Postelia Palmaeformis is known as sea palm.
(iv) Endosperm is triploid in pinus.

🎯 Exam Tip: Clearly differentiate between gametophyte and sporophyte stages, especially in lower plants. Remember the ploidy level of endosperm in gymnosperms vs. angiosperms.

Question 3.
(i) Apogamy and Apospory is common in pteridophytes
(ii) Spore bearing leaves in pteridophytes are known as a sorus
(iii) Branches of limited growth and branches of unlimited growth are seen in gymnosperm
(iv) Cambium occur in gymnosperm as in dicots

🎯 Exam Tip: Differentiate between sori (clusters of sporangia) and sporophylls (leaves bearing sporangia). Note the growth patterns and presence of cambium in gymnosperms.

Question 4.
(i) Fungi play important role in soil conservation
(ii) Vascular cryptogams were predominant in the paleozoic era
(iii) Gymnosperms were dominant in the early cretaceous period.
(iv) Angiosperms appeared during the Jurassic period

🎯 Exam Tip: Remember the geological periods and which plant groups were dominant during each era. This helps in understanding plant evolution.

Question 5.
(i) Polyembryony is traced in Pteridophyta
(ii) Vessels are present in Gnetum and ephedra
(iii) Heterosporus condition is seen in Lycopodium
(iv) Corolloid root occur in Cycas

🎯 Exam Tip: Note the exceptions like vessels in Gnetum and Ephedra, and specific root types like coralloid roots in Cycas, as these are important distinguishing features.

Question 6. Which one of the following is the correct statement regarding Phaeophyta
(a) It is commonly known as Red Algae
(b) The plant body has fronds, stipe & hold fast
(c) The reserve material is Floridian starch
(d) Sexual reproduction is isogamous
Answer: (b) The plant body has fronds, stipe & holdfast
In simple words: Phaeophyta are brown algae, not red algae. Their body structure typically includes fronds (leaf-like), a stipe (stem-like), and a holdfast (root-like structure for attachment). Their reserve food is laminarin and mannitol, not Floridian starch. Sexual reproduction can be isogamous, anisogamous, or oogamous.

🎯 Exam Tip: Familiarize yourself with the common names, plant body structure, reserve food, and types of sexual reproduction for major algal groups (green, red, brown).

Question 7. Choose the right statement regarding leaves of Pteridiumsp.
(a) It is used as food
(b) Green dye is derived from it.
(c) It is used as bio-fertilizer
(d) It is an ornamental foliage plant
Answer: (b) Green dye is derived from it.
In simple words: Pteridium species, commonly known as bracken fern, can be used to make green dye. While some ferns have other uses, this is a specific use for Pteridium.

🎯 Exam Tip: Learn some specific economic uses or unique characteristics for key plant examples in each group.

Question 8. Which one of the following is a correct statement regarding Bryophyta
(a) Mostly terrestrial plants so water is not essential for reproduction
(b) The gametophyte is dominant but the sporophyte is independent
(c) They have well-developed xylem and phloem tissues
(d) They are the simplest land inhabiting cryptogams lacking vascular tissues.
Answer: (d) They are the simplest land inhabiting cryptogams lacking vascular tissues.
In simple words: Bryophytes are simple land plants that do not have specialized water-conducting tissues (xylem and phloem). They need water for reproduction, and their sporophyte depends on the dominant gametophyte.

🎯 Exam Tip: Remember that bryophytes are non-vascular plants and require water for fertilization, classifying them as "amphibians of the plant kingdom".

Question 10. Choose the correct statement regarding the common characters of Gymnosperm and Angiosperm only
(a) Pollen tube help in the transfer of male nucleus & fertilization is Siphonogamous
(b) Heterospory is of common occurrence
(c) Vessels are the chief water-conducting element
(d) Pollination is by Anemophilous method only
Answer: (a) Pollen tube help in the transfer of the male nucleus & fertilization is Siphonogamous.
In simple words: In both gymnosperms and angiosperms, the pollen tube grows to carry the male reproductive cells to the female egg. This type of fertilization, where the pollen tube acts as a carrier, is called siphonogamy.

🎯 Exam Tip: Siphonogamy is a key evolutionary development that allowed gymnosperms and angiosperms to become independent of water for fertilization.

Question 11. Look at the picture and find out the correct answer.
(a) Gemmae of Marchantia
(b) Thallus of Riccia
(c) The gametophyte of Anthoceos
(d) The tubers of Anthoceos

Question 5. Pollination is not entomophilous in
(a) Hibiscus
(b) Mangifera
(c) Missing option from source
(d) Cycas
Answer: (d) Cycas
In simple words: Cycas plants are not pollinated by insects. Instead, their pollen is carried by wind, which is called anemophily.

🎯 Exam Tip: Remember that entomophilous means insect pollination. Knowing the specific pollination methods for different plant groups helps in classification.

Question 6. The following one is not a monoecious plant
(a) Pinus
(b) Cycas
(c) Alnus
(d) Ginkgo
Answer: (b) Cycas
In simple words: Cycas plants are dioecious, meaning male and female reproductive parts grow on separate individual plants. Pinus, Alnus, and Ginkgo, however, are monoecious, having both male and female structures on the same plant.

🎯 Exam Tip: Understand the terms "monoecious" (both sexes on one plant) and "dioecious" (sexes on separate plants) for plant classification.

Question 7. Which one of the following is not the correct statement regarding Algae?
(a) The study of Algae is known as Phycology
(b) A wide range of thallus organization is found in Algae
(c) Algae are eukaryotic except Blue Green Algae
(d) They are the simplest plant group with root stem and leaves
Answer: (d) They are the simplest plant group with root stem and leaves
In simple words: Algae are simple plants that do not have true roots, stems, or leaves like more complex plants do. Blue-green algae are prokaryotic, which means they do not have a true nucleus, unlike other algae.

🎯 Exam Tip: Algae are often called thallophytes because their plant body is a simple thallus, lacking true roots, stems, and leaves.

IV. Find out the true or false statements from the following and on that basis find the correct answer.

Question 1.
(i) Chara thallus is encrusted with calcium carbonate
(ii) Siliceous wall occurs in the cell wall of Diatom
(iii) Soil inhabiting algae - Fritshchiella
(iv) Cladophora crispate is growing now

🎯 Exam Tip: Pay close attention to the specific characteristics of different algal groups, especially their cell wall composition and habitat.

Question 2.
(i) Prothallus develop into a sporophyte
(ii) Algae growing on snow is known as cryptophytes
(iii) The common name of Postelia Palmaeformis is known as sea palm.
(iv) Endosperm is triploid in pinus.

🎯 Exam Tip: Clearly differentiate between gametophyte and sporophyte stages, especially in lower plants. Remember the ploidy level of endosperm in gymnosperms vs. angiosperms.

Question 3.
(i) Apogamy and Apospory is common in pteridophytes
(ii) Spore bearing leaves in pteridophytes are known as a sorus
(iii) Branches of limited growth and branches of unlimited growth are seen in gymnosperm
(iv) Cambium occur in gymnosperm as in dicots

🎯 Exam Tip: Differentiate between sori (clusters of sporangia) and sporophylls (leaves bearing sporangia). Note the growth patterns and presence of cambium in gymnosperms.

Question 4.
(i) Fungi play important role in soil conservation
(ii) Vascular cryptogams were predominant in the paleozoic era
(iii) Gymnosperms were dominant in the early cretaceous period.
(iv) Angiosperms appeared during the Jurassic period

🎯 Exam Tip: Remember the geological periods and which plant groups were dominant during each era. This helps in understanding plant evolution.

Question 5.
(i) Polyembryony is traced in Pteridophyta
(ii) Vessels are present in Gnetum and ephedra
(iii) Heterosporus condition is seen in Lycopodium
(iv) Corolloid root occur in Cycas

🎯 Exam Tip: Note the exceptions like vessels in Gnetum and Ephedra, and specific root types like coralloid roots in Cycas, as these are important distinguishing features.

Question 6. Which one of the following is the correct statement regarding Phaeophyta
(a) It is commonly known as Red Algae
(b) The plant body has fronds, stipe & hold fast
(c) The reserve material is Floridian starch
(d) Sexual reproduction is isogamous
Answer: (b) The plant body has fronds, stipe & holdfast
In simple words: Phaeophyta are brown algae, not red algae. Their body structure typically includes fronds (leaf-like), a stipe (stem-like), and a holdfast (root-like structure for attachment). Their reserve food is laminarin and mannitol, not Floridian starch. Sexual reproduction can be isogamous, anisogamous, or oogamous.

🎯 Exam Tip: Familiarize yourself with the common names, plant body structure, reserve food, and types of sexual reproduction for major algal groups (green, red, brown).

Question 7. Choose the right statement regarding leaves of Pteridiumsp.
(a) It is used as food
(b) Green dye is derived from it.
(c) It is used as bio-fertilizer
(d) It is an ornamental foliage plant
Answer: (b) Green dye is derived from it.
In simple words: Pteridium species, commonly known as bracken fern, can be used to make green dye. While some ferns have other uses, this is a specific use for Pteridium.

🎯 Exam Tip: Learn some specific economic uses or unique characteristics for key plant examples in each group.

Question 8. Which one of the following is a correct statement regarding Bryophyta
(a) Mostly terrestrial plants so water is not essential for reproduction
(b) The gametophyte is dominant but the sporophyte is independent
(c) They have well-developed xylem and phloem tissues
(d) They are the simplest land inhabiting cryptogams lacking vascular tissues.
Answer: (d) They are the simplest land inhabiting cryptogams lacking vascular tissues.
In simple words: Bryophytes are simple land plants that do not have specialized water-conducting tissues (xylem and phloem). They need water for reproduction, and their sporophyte depends on the dominant gametophyte.

🎯 Exam Tip: Remember that bryophytes are non-vascular plants and require water for fertilization, classifying them as "amphibians of the plant kingdom".

Question 10. Choose the correct statement regarding the common characters of Gymnosperm and Angiosperm only
(a) Pollen tube help in the transfer of male nucleus & fertilization is Siphonogamous
(b) Heterospory is of common occurrence
(c) Vessels are the chief water-conducting element
(d) Pollination is by Anemophilous method only
Answer: (a) Pollen tube help in the transfer of the male nucleus & fertilization is Siphonogamous.
In simple words: In both gymnosperms and angiosperms, the pollen tube grows to carry the male reproductive cells to the female egg. This type of fertilization, where the pollen tube acts as a carrier, is called siphonogamy.

🎯 Exam Tip: Siphonogamy is a key evolutionary development that allowed gymnosperms and angiosperms to become independent of water for fertilization.

Question 11. Look at the picture and find out the correct answer.
(a) Gemmae of Marchantia
(b) Thallus of Riccia
(c) The gametophyte of Anthoceos
(d) The tubers of Anthoceos

Answer: (d) The tubers of Anthoceos
In simple words: The picture shows tubers, which are swollen underground stems used for storing food. In the plant Anthoceros, these tubers are used for vegetative reproduction, allowing new plants to grow from these storage organs.

🎯 Exam Tip: When identifying plant parts from a diagram, look for key features. Tubers are typically swollen and subterranean, indicative of storage and asexual reproduction.

Question 12. Look at the picture and find out the correct answer

Answer: Reimer's classification divides Pteridophytes into five main groups, which are further split into 19 orders and 48 families. These main groups are:
1. Psilophytopsida
2. Psilotopsida
3. Lycopsida
4. Sphenopsida
5. Pteropsida
In simple words: Reimer organized Pteridophytes into five main categories, which helps group them based on their features.

🎯 Exam Tip: When asked for a classification, list the main groups clearly and note any sub-divisions mentioned.

Question 13. What is amber? Which group of plants produce amber?
Answer: Amber is a hardened plant sap that works like a natural preservative. It doesn't break down easily, so it can trap and protect ancient life forms for millions of years. This allows scientists to study ancient ecosystems in great detail. This special sap is made by a type of Gymnosperm tree called Pinites succinifera.
In simple words: Amber is old, hardened tree sap that keeps things preserved, and it comes from Gymnosperm plants.

🎯 Exam Tip: Remember that amber is fossilized tree resin and is famously known for preserving ancient insects and other small organisms.

Question 14. What is meant by Siphonostele?
Answer: A siphonostele is a type of plant stem where the central woody tissue (xylem) is surrounded by the food-carrying tissue (phloem), and there is a core of soft tissue called pith in the very middle. This arrangement helps transport water and nutrients efficiently throughout the plant. This complex arrangement of vascular tissues is a key evolutionary feature in many plants. For example, the plant Marsilea has a siphonostele. There are actually six different kinds of siphonosteles, including ectophloic and amphiphloic types, which describe where the phloem is located.
In simple words: A siphonostele is a plant stem structure where the water-carrying part (xylem) is around the central soft part (pith), and then food-carrying parts (phloem) surround the xylem.

🎯 Exam Tip: Focus on the presence of pith in the center and the arrangement of xylem and phloem layers around it when defining a siphonostele.

Question 15. What is Amber? Where have you noticed it?
Answer: Amber is a special plant sap that has hardened over time into a fossil. It is known for preserving ancient insects and plant parts. This natural preservative stops things from decaying. Many people have seen amber in movies like 'Jurassic Park', where mosquitoes containing dinosaur blood were preserved in it.
In simple words: Amber is fossilized tree resin that preserves old things, often seen in movies like Jurassic Park.

🎯 Exam Tip: Always mention both the definition of amber and a common example of its appearance or use, like in pop culture or scientific findings.

Question 16. What is the word Jurassic - denote?
Answer: The term 'Jurassic' refers to a specific time period in Earth's history, known as the Jurassic period. This era was famous for being the age of dinosaurs, and it falls within the larger Mesozoic era. It was a time of immense biodiversity and significant geological activity. During this time, many Gymnosperm plants were also very common and grew widely.
In simple words: Jurassic is a period when dinosaurs lived, part of the Mesozoic era, and many Gymnosperm plants were common then.

🎯 Exam Tip: Connect "Jurassic" with the age of dinosaurs and its geological era (Mesozoic) for a complete answer.

3 Marks

Question 1. Give the widely accepted outline classification for plants.
Answer: The widely accepted classification divides the plant kingdom into two main subkingdoms: Cryptogams and Phanerogams. This classification helps scientists organize the vast diversity of plant life based on their reproductive and structural features.
Cryptogams are non-flowering and non-seed-producing plants, including:
1. Algae
2. Bryophyta
3. Pteridophyta
Phanerogams are flowering and seed-producing plants, which include:
1. Gymnosperm (non-flowering, naked seed-bearing plants)
2. Angiosperm (flowering plants), which are further divided into:
(a) Dicots
(b) Monocots
In simple words: Plants are classified into Cryptogams (no flowers or seeds like algae, mosses, ferns) and Phanerogams (flowers and seeds like gymnosperms and angiosperms).

🎯 Exam Tip: When outlining a classification, ensure you cover the main divisions and list the key plant groups under each, highlighting their defining features.

Question 2. Give the total number of plant groups in the world and India.
Answer: Here is a breakdown of the estimated number of known plant species for different groups, both globally and specifically in India. This data highlights the rich plant diversity found in India compared to the global numbers.

🎯 Exam Tip: When presenting numerical data, always use a clear table format and ensure all values are accurately transcribed.

Question 3. Name the 3 types of life cycles seen in plants?
Answer: Plants show three main types of life cycles, which describe how they grow and reproduce. These different cycles reflect evolutionary adaptations to various environmental conditions. These types are:
1. Haplontic life cycle
2. Diplontic life cycle
3. Haplodiplontic life cycle
In simple words: Plants follow one of three life cycles: haplontic, diplontic, or haplodiplontic.

🎯 Exam Tip: Clearly list all three life cycle types. For higher marks, briefly explain what each name implies (haploid dominant, diploid dominant, or both).

Question 4. More than half of the total productivity of the world is done by Marine Algae - Justify.
Answer: Yes, it is true that marine algae are responsible for more than half of the world's total productivity. This is because oceans and seas cover about two-thirds of the Earth's surface. A huge portion of this area is home to marine algae, which are the main primary producers there. They create nearly half of all the food and energy produced globally. This makes marine algae crucial for maintaining the oxygen levels and food webs in aquatic environments. All other sea creatures depend on these algae for their survival.
In simple words: Marine algae produce over half of the world's food and oxygen because they live in most of the ocean, which covers two-thirds of Earth.

🎯 Exam Tip: To justify this statement, emphasize the vast area of oceans and the role of marine algae as primary producers in aquatic food chains.

Question 5. Classify Algae according to F.E.Fritsch.
Answer: F.E. Fritsch, in his detailed work on the structure and reproduction of Algae in 1935, classified algae into 11 main classes. This detailed classification system is fundamental for studying algal diversity and evolution. These classes help group different types of algae based on their characteristics:
1. Chlorophyceae
2. Xanthophyceae
3. Chrysophyceae
4. Bacillariophyceae
5. Cryptophyceae
6. Dinophyceae
7. Chloromondineae
8. Euglenophyceae
9. Phaeophyceae
10. Rhodophyceae
11. Cyanophyceae
In simple words: F.E. Fritsch divided algae into 11 groups like Chlorophyceae, Phaeophyceae, and Rhodophyceae, based on how they look and reproduce.

🎯 Exam Tip: Ensure you list all 11 classes accurately as per F.E. Fritsch's classification. It's often helpful to memorize the larger, more common groups first.

Question 6. Write about Reproduction in Chlorophyceae.
Answer: Chlorophyceae, a group of green algae, reproduce in three main ways: vegetative, asexual, and sexual. This versatility in reproduction allows them to adapt to diverse environmental conditions.

🎯 Exam Tip: When describing reproduction, categorize it into vegetative, asexual, and sexual, providing specific examples or terms for each method.

Question 7. Write down the economic importance of Bryophyte?
Answer: Bryophytes, like mosses and liverworts, have several important economic uses and ecological benefits. Their unique properties make them valuable in various fields from fuel to medicine.

🎯 Exam Tip: When listing economic importance, try to provide a specific bryophyte name for each use to demonstrate detailed knowledge.

Question 8. List down the economic importance of Pteridophytes.
Answer: Pteridophytes, which include ferns and their relatives, are important for several reasons, from their uses in traditional medicine to environmental benefits. These plants, often overlooked, play diverse roles in both human society and natural ecosystems.

🎯 Exam Tip: Remember to link specific pteridophyte names with their corresponding economic uses to show a deeper understanding.

Question 9. Name the three classes of Bryophytes, according to Proskauer.
Answer: According to Proskauer's classification, Bryophytes are divided into three main classes. This classification helps distinguish different groups within bryophytes based on their structural and reproductive characteristics. These classes are:
1. Hepaticopsida
2. Anthocerotopsida
3. Bryopsida
In simple words: Proskauer classified Bryophytes into three groups: Hepaticopsida, Anthocerotopsida, and Bryopsida.

🎯 Exam Tip: For specific classifications, ensure the names of the classes are spelled correctly and listed clearly.

Question 10. List down the salient features of Angiosperm.
Answer: Angiosperms, also known as flowering plants, have several key features that make them the most diverse and widespread plant group. Their reproductive success is largely due to the co-evolution with pollinators and effective seed dispersal mechanisms.
• Vascular system - Xylem and Phloem are well developed.
• Flowers are produced (instead of cones).
• Ovules (embryosac and seeds) - remain enclosed in the ovary/fruit.
• Pollen tube - Helps in fertilization; water is not always necessary.
• The presence of double fertilization is one of the unique features.
In simple words: Angiosperms have well-developed vascular systems, produce flowers, enclose ovules in ovaries, use pollen tubes for fertilization, and perform double fertilization.

🎯 Exam Tip: Highlight the unique features of angiosperms, such as flowers, enclosed ovules, and double fertilization, as these are critical distinguishing characteristics.

Question 11. Differentiate between Dicotyledons & Monocotyledons.
Answer: Dicotyledons (dicots) and Monocotyledons (monocots) are two major groups of flowering plants, and they have distinct differences in their morphological and anatomical features. These differences are fundamental for understanding plant diversity and evolution.

🎯 Exam Tip: Organize your answer into clear categories like morphological and anatomical features, listing contrasting points for each group. Mentioning cotyledons, venation, root system, and vascular bundle arrangement is crucial.

5 Marks

Question 1. Classify Algae on the basis of their habitats.
Answer: Algae are found in a wide variety of habitats, and they can be classified based on where they live. Their ability to adapt to different environments showcases their incredible diversity and ecological importance.

🎯 Exam Tip: When classifying by habitat, remember to provide at least one specific example of an alga for each habitat type to strengthen your answer.

Question 2. Give an account of General Characteristics of Algae?
Answer: Algae are a diverse group of simple, plant-like organisms with several key characteristics related to their structure, cell walls, and reproduction. Their varied characteristics allow them to thrive in diverse aquatic and terrestrial environments. Here are some general features:

🎯 Exam Tip: When describing general characteristics, organize your answer into clear categories (e.g., thallus organization, cell wall composition, reproduction) and provide specific examples for each point.

Question 3. Give an account of Phaeophyceae.
Answer: Phaeophyceae, commonly known as brown algae, are a large group of multicellular algae, including many seaweeds. They have distinct features related to their habitat, structure, pigments, and reproduction. Brown algae are a significant component of marine ecosystems, forming kelp forests that provide habitat for numerous species.

🎯 Exam Tip: When describing a specific algal class, remember to include its primary habitat, unique pigments, storage compounds, and common reproductive strategies.

Question 4. Give an account of Rhodophyceae (red algae) criteria.
Answer: Rhodophyceae, or red algae, are predominantly marine organisms known for their distinctive red pigments. They exhibit a range of unique characteristics that set them apart from other algal groups. Red algae are economically important as sources of agar and carrageenan, used in food and various industries.

🎯 Exam Tip: For red algae, highlight their marine habitat, unique red pigments (phycoerythrin, phycocyanin), storage product (Floridean starch), and the type of sexual reproduction.

Question 6. General characteristic features of Bryophytes.
Answer: Bryophytes are simple non-vascular plants, including mosses, liverworts, and hornworts, often called 'amphibians of the plant kingdom' due to their need for water for reproduction. They play important ecological roles as pioneer species in barren environments and in moisture retention. They have several key features:

🎯 Exam Tip: Focus on the absence of vascular tissue, dependence on water for reproduction, and the dominant gametophyte phase as key features of bryophytes.

Question 7. Write down differences between Gymnosperm & Angiosperm.
Answer: Gymnosperms and Angiosperms are two major groups of seed-producing plants, but they have distinct differences in their reproductive structures and overall plant characteristics. Understanding these differences helps us appreciate the evolutionary success and diversity of both plant groups.

🎯 Exam Tip: Structure your answer as a comparison table, clearly highlighting key differences in features like seeds, flowers, fruit, vascular tissues, and fertilization processes.

Question 8. Write down the Economic Importance of Gymnosperm.
Answer: Gymnosperms are useful to humans in many ways, providing various products and services. Here is a list of their economic importance:

🎯 Exam Tip: When listing economic importance, focus on specific plant names and their corresponding uses to show detailed knowledge.

Question 9. Give an account of Fossil plants.
Answer: Fossil plants are ancient plant remains preserved in rocks, providing insights into Earth's past plant life and climates. India has several rich sites where these plant fossils are found:

🎯 Exam Tip: Remember both the location of major fossil parks and examples of fossil types for each plant group to score well on this question.