Morphology of Flowering Plants

Transcription

1 Morphology of Flowering Plants I. Answer the following in one or two lines (1 mark each) 1. What is meant by adventitious root? Roots that arise from parts of the plants other than the radical. 2. What are stilt roots? Supporting roots arising from lower nodes of stem like in sugarcane. 3. What is the function of prop roots? Prop roots arising from the horizontal branches of the stem grow vertically downwards and provide mechanical support to the huge trees. 4. Where are the haustorial roots found? Found in parasitic plants. 5. Define nodulated roots. The roots bear irregular swellings called root nodules and generally occur in legumes. Help in nitrogen fixation. 6. What is the use of root cap? It protects the tender apex of root. 7. Name the thread like structures present on region of maturation of root tip. Root hairs. 8. From which part of the embryo is the root system formed. Radicle 9. From which part of the embryo is the shoot system formed. Plumule 10. Name the region of the stem where the leaf arises. Node 11. What is meant by phylloclade? Stem modified to carry out the function of photosynthesis. 12. What is the function of leaf? To carry out photosynthesis. 13. What is the swollen leaf base known as? Pulvinus leaf base. 14. What are the two lateral small leaf like structures at the base known as? Stipules 15. What type of leaf base do monocots have? Sheathing leaf base 16. What is the function of petiole? Holds the lamina/leaf bladeupright facing toward the light. 17. Define venation. Arrangement of veins & veinlets on a leaf. 18. Define phyllotaxy. Arrangement of leaves on the stem/b ranch 19. What is a phyllode? Petiole flattened and photosynthetic in nature. 20. Which part/organ of a plant is modified to trap insects in insectivorous plants? Leaf. 21. Name the different types of compound leaves. Pinnately compound & Palmately compound. 22. Name the reproductive part of an angiospermic plant. Flower 23. What is the reduced leaf found at the base of pedicel known as? Bract

2 24. What is the function of sepal? Protects flower in the bud stage. 25. What is a perianth? Calyx & corolla are indistinct and are collectively known as perianth. 26. What is meant by monoecious plant? When both male and female flowers are found on the same plant, they are known as monoecious. 27. What is a diecious plant? When male and female flowers are found on different plants, they are known as diecious. 28. What is meant aestivation? The mode of arrangement of sepals or petals in floral bud with respect to the other members of the same whorl. 29. What is a sterile stamen known as? Staminode 30. What is a epipetalous/epiphyllous stamen? Stamens attached to the petals/ stamens attached to the perianth 31. What is meant by polyandrous stamens? Stamens are free. 32. What is a drupe? Fruit developed from monocarpellary superior ovary with a single seed is known as drupe. 33. What is a monoadelphous stamen? Stamens united into one bunch or one bundle. 34. What is a diadelphous stamen? Stamens fused to form two bundles. 35. What is polyadelphous stamen? Stamens fused to form more than two bundles. 36. Name the parts of a carpel. Stigma, style & ovary. 37. What is a parthenocarpic fruit? Fruits developed from the ovary without fertilization. 38. What is meant by coleoptiles? Plumule covered by a sheath called coleoptile. 39. What is meant by coleorhiza? Radicle covered by a sheath called coleorhiza. II. Answer the following briefly (2 marks each). 1. Give the difference between tap root & fibrous root. Tap root originates from the radical & is made up of primary, secondary & tertiary roots found in dicot plants. Whereas fibrous roots originates from the base of stem with several roots replacing the primary root and found in monocot plants. 2. List out the functions of root. Absorption of water and mineral from soil Anchorage of the plant body Storing reserve food material. Synthesis of plant growth regulators. 3. Name the root modification for respiration with example. Pneumatophores eg. Rhizophora 4. Name the various types of epiphytic roots & give their function. Clinging roots for attachment/support and aerial roots containing velamen tissue for the absorption of moisture from air.

3 5. Give the functions of stem. Bearing branches, leaves, flowers and fruits. Conduction of water and minerals. Green stems also carry out photosynthesis. Food storage, support, protection and vegetative propagation. 6. Name the modifications of stem for support & protection with examples. Tendrils cucumber, pumpkin Thorns Bougainvellia, Citrus 7. Differentiate between simple and compound leaf. In a simple leaf the lamina is entire without any incision whereas in a compound leaf the incision reachesthe midrib dividin the leaf into lets. 8. Give the different types of venation with examples. Reticulate venation eg. Mango Parallel venation eg. Bannana 9. Differentiate between reticulate & parallel venation. In reticulate venation the veins & veinlets are in the form of network whereas in parallel venation the veins are arranged parallel to one another. 10. Give the difference between paripinnate imparipinnate compound leaf with example. The paripinnate leaf has even number of leaflets at the tip, eg. Tamarind. Whereas in a imparipinnate leaf odd number of leaflets are seen, eg. Neem, rose. 11. Give the difference between monothecous & dithecous anthers. In monothecous anthers there only one lobe whereas in dithecous anthers there are two anther lobes. 12. Name the various parts of a flower. Pedicel, calyx, corolla, androecium & gynoecium. 13. Give the difference between actinomorphic & zygomorphic flower. An actinomorphic flower can be divided into two equal halves in any plane whereas in zygomorphic flower it can be divided into two equal halves in only one plane. 14. Give the difference between apocarpous & syncarpous ovary. In apocarpous ovary the carpels are free whereas in syncarpous ovary the carpels are fused. 15. Give the difference between a complete flower & an incomplete flower. In a complete flower all the floral parts are present, whereas in an incomplete flower one of the reproductive parts is absent. 16. What do the following symbols stand for K, C, A & G. K Calyx C Corolla A Androecium G - Gynoecium 17. Give the difference between polypetalous & gamopetalous corolla. In polypetalous corolla ther petals are totally free whereas in gamopetalous corolla the petals are fused together. 18. Give the floral formulas for the families a) Fabaceae b) Solanaceae d) Liliaceae a) Br K (5) C 1+2+(2) A (9)+1 G 1 b) Ebr. K (5) C (5) A 5 G (2) c) Br. P 3+3 A 3+3 G (3)

4 III. Answer the following questions in few sentences (3 marks each). 1. What are the various modification of root for food storage? Give examples for each. Fusiform (radish); Napiform (turnip, beetroot); Conical (carrot); Tuberous (sweet potato);fasciculated (Asparagus) 2. Explain the shoot system. The above-ground or aerial part is known as shoot system made up of stem & its branches, leaves, flowers & fruits. Flowers are the modified shoots and fruits are the products of flowers. Leaves are the appendages. 3. Give the function of the following modifications a) tendril; b) thorn & c) underground stem. a)tendril mechanical support b)thorn protection c)underground stem food storage & vegetative propagation. 4. Explain the different types of phyllotaxy observed in plants. Alternate: In this type of leaf arrangement, a single leaf arises at each node in alternate manner, e.g. China rose, mustard, sunflower, etc. Opposite: In this type of leaf arrangement, a pair of leaves arise at each node. The leaves lie opposite to each other in this case, e.g. Calotropis, guava, etc. Whorled: In this type of leaf arrangement, more than two leaves arise at a node, e.g. Alstonia. 5. What is an inflorescence? Explain the different types of inflorescences. Inflorescence is the arrangement of flowers on the floral axis of stem. Racemose : the main axis continues to grow; the flowers are borne laterally in an acropetal succession. Cymose : the main axis terminates in flower, hence limited to grow. The flowers are borne in a basipetal order. 6. Explain the different types of symmetry observed in plants. Actinomorphic: radially symmetrical can be cut into two equal halves in any plane. Zygomorphic: bilaterally symmetrical can be cut intotwo equal halves in only one plane. Asymmetrical: when a flower cannot be divided into two equal half in any plane. 7. Based on the position of ovary, name the different types of flowers. Hypogynous, epigynous & perigynous. 8. Draw a neat labeled diagram of drupe of mango. 9. Draw the floral diagram of family a) Fabaceae b) Solanaceae c) Liliaceae a)fabaceae

5 b)solanaceae c)liliaceae IV. Answer the following questions (5 marks each). 1. Explain the various regions of the root with the help of a neat labeled diagram. The various of the regions of the root are - Root Cap : The root is covered at the apex by the thimble-like structure which protects the tender apical part. Region of meristematic activity : Cells of this region have the capability to divide. The cells of this region are very small, thin-walled and with dense protoplasm. Region of elongation : Cells of this region are elongated and enlarged. Region of Maturation : This region has differentiated into matured cells. Some of the epidermal cells of this region form thread-like root hairs, which absorbs water and minerals from the soil. 2. Give the various modifications of stem with examples. The various modifications of stem are Modification for food storage: The underground stems of potato, ginger, turmeric, Colocasia, etc. are modified for food storage. Modifications for climbing: In some plants, stem tendrils develop form axillary buds. These are slender and spirally coiled structures. A tendril helps the plant to climb to a support, e.g. cucumber, pumpkin, grapevine, etc. Modification for defence: In some plants, the axillary buds are modified into woody, straight and pointed thorns. Such thorns protect the plant from browsing animals, e.g. Citrus, Bougainvillea Modification for photosynthesis: In some plants of arid regions, the stems are modified into flattened or fleshy cylindrical structures. The flattened structure can be seen in Opuntia and the cylindrical structure can be seen in Euphorbia. Such structures contain chlorophyll and photosynthesis happens in them and are known as phylloclades. Modifications for vegetative propagation.

6 3. Explain the various modifications of stem for vegetative propogation with examples. In some plants, the underground stems spread to new areas and give rise to new plants when the older plants die, and are known as runners e.g. grass and strawberry. In some plants, lateral branches come out from the main axis. These branches arch downward to touch the ground; after some growth. These branches then give rise to new plants, and are known as stolons e.g. mint and jasmine. In some aquatic plants, a lateral branch bears a bunch of leaves and a tuft of roots at nodes, new plants emerge from such nodes & is known as offset e.g. Pistia and Eichhornia. In some plants, the lateral branches emerge from the basal and underground portion of the main stem. Such branches grow horizontally beneath the soil and come out upward to give rise to leafy shoots, they are known as suckers e.g. banana, pineapple and Chrysanthemum. 4. Explain the various parts of a leaf with a neat labeled diagram. A leaf is laterally borne out of the stem. It is usually a flattened structure. The leaf develops at the node. It bears a bud in its axil. The axillary bud subsequently develops into a branch. Leaves originate from shoot apical meristem. They are arranged in acropetal order. Main parts of leaf are leaf base, petiole and lamina. The leaf is attached to the stem by the leaf base. It may bear two lateral small leaf-like structures called stipules. In monocot plants, the leaf base expands to form a sheath. The sheath partially or completely covers the stem. 5. Explain the various modifications of leaf along with their function & example. The various modifications of the leaf are: Tendrils: In some plants, leaves are modified into tendrils to assist in climbing, e.g. pea. Spines: In some plants, leaves are modified into spines for defence, e.g. cactus. The leaf spine in cacti and in some other xerophytes also helps in reducing water loss by preventing transpiration. Bulb: In some plants, the leaves are modified into bulb for food storage, e.g. garlic and onion. In Australian acacia, the leaves are small the short-lived. The petioles expanded, become green and synthesize food and are known as phyllodes. In insectivorous plant leaves are modified to trap insects e.g. pitcher plant, Venus fly trap. 6. Draw a neat labeled diagram of the basic structure of a flower.

7 7. Explain the different types of aestivation with help of diagram. The mode of arrangement of sepals or petals in the floral bud with respect to the other members of the same whorl is known as aestivation. Valvate : sepals or petals in a whorl just touch one another at the margin, without overlapping. E.g. Calotropis. Twisted : one margin of the appendage overlaps that of the next one and so on. E.g. china rose. Imbricate : the margin of sepals or petals overlap one another but not in any particular direction as in Cassia and gulmohur. Vexillary : The large petal (standard) overlaps the two lateral petals (wings) which in turn overlap the two smallest anterior petals (keel). 8. What is meant placentation? Explain the different types of placentation with examples. Placentation is the arrangement of ovules within the ovary is known as Placentation. Marginal: Placenta forms a ridge along the ventral suture of ovary eg. pea Axile: Margins of carpels fuse to form central axis eg. Hibiscus Parietal: Ovules develop on inner wall of ovary eg. mustard Free central: Ovules borne on central axis, lacking septa eg. chilly Basal: Placenta develops at the base of ovar eg. sunflower/maize 9. With the help of diagram explain the structure of dicot seed. Structure of dicotyledonous seed : Outer most covering of seed is seed coat. Seed coat has Outer testa Inner tegmen. The hilum is a scar on the seed coat, the point of attachment of developing seed with the fruit. Above the hilum is a small pore called the micropyle. Embryo present inside the seed coat, consists of - An embryonal axis. Two cotyledons Cotyledons are fleshy and store reserve food. At the two end of embryonal axis are present the radicle and the plumule. In some seed endosperm store the reserve food as in castor. Mature seed without endosperm called non-albuminous seed or non-endospermous as in bean, gram and pea.

8 10. With the help of a neat labeled diagram explain the structure of moncot seed. Structure of monocotyledonous Seed : Generally monocotyledonous seeds are endospermic, orchids are non-endospermic. In seeds of cereals such as maize, the seed coat is fused with the fruit wall. The outer covering of separates the embryo by a proteinous layer called aleurone layer. Embryo is small and located one side of the endosperm and consists of One large shield shaped cotyledon known as scutellum. A short axis with radicle and plumule. Plumule covered by a sheath called coleoptile. Radicle covered by a sheath called coleorhiza. 11. Give the characteristic features of family Fabaceae. Roots with nodules Leaves pulvinate, alternate, generally compound Flowers zygomorphic, bisexual hypogynous or perigynous, bracteate Calyx sepals 5, gamosepalous Corolla petals 5, gamopetallous, papilionaceous, vexillary aestivation Androecium stamens 10, monoadelphous or diadelphous (9)+1 condition Gynoecium monocarpellary, unilocular ovary with ovules on marginal placentation. Fuit legume or lomentum 12. Give the characteristic features of family Solonaceae. Adnation of petiole with internodes Flower actinomorphic, pentamerous & hypogynous Calyx sepals 5, gamosepalous, persistent Corolla petals 5, gamopetalous with twisted aestivation Androecium stamens 5, epipetalous, dithecous, basifixed Gynoecium biarpellary, syncarpous, bilocular, with superior ovary obliquely placed; ovules many on thick swollen axile placentation. Fruit a berry or capsule. 13. Give the characteristic features of family Liliaceae. Leaves parallel veined Flowers bisexual, trimerous & hypogynous Perianth Tepals 6, in two whorls of three each Androecium stamens 6, in two whorls of three each Gynoecium tricarpellary syncarpous, trilocular with superior ovary, ovules on axile placentation. Fruit a capsule.

9 14. Give scientific names of any five economically important plants belonging to the family Fabaceae. Cajanus cajan pigeon pea/red gram/thur dhal Cicer arietinum chick pea/bengal gram/channa Pisum sativum pea Glycine max soya bean Phaseolus mungo (Vigna mungo) black gram Phaseolus radiatus (Vignaradiata) green gram Dolichos lablab syn. Lablab purpureus avare kalu Phaseolus vulgaris french bean (hulli kayi) Vicia faba broad bean (Chapparadavare) Cyamopsis tetragonoloba cluster bean Arachis hypogea groundnut Trigonella foenum-graecum fenugreek/methi Macrotyloma uniflorum horse gram (huruli) Vigna unguiculata cow pea (alasande) 15. Give scientific names of any five economically important plants belonging to the family Solonaceae. Solanum tuberosum (Potato) is used as vegetable. Solanum melongena (Brinjal/egg plant) is used in vegetable. Solanum nigrum is used in medicine. Capsicum frutescens (Simla Mirch) Capsicum annum (Chilly) Lycopersicum esculatum (Tomato) is used as vegetable (avagode-hannu) Nicotiana tobacum (Tobacco) the leaves of plant are used as tobacco. Datura alba (Dhatura) seed are narcotic and poisonous. Petunia alba is ornamental plant. Cestrum nocturnum (Rat ki Rani) ornamental plant. Atropa belladona medicinal plant Withania somnifera (Aswagandha) medicinal plant 16. Give scientific names of any five economically important plants belonging to the family Liliaceae. Alium cepa (onion) Asparagus racemosus - roots edible, medicinal also Alium sativum (garlic) - medicinal use also Aloe vera extract from the plant used as a purgative and for treating liver disorders. Crinum latifolium (Sukh darshan plant; pink striped trumphet lily) medicinal plant Crinum asiaticum (spider lily) for urinary problems Smilax zeylanica for curing arthritis Dracaena termiflora Lilium candidum Gloriosa superba (glory lily; tiger s claw) a fencing plant