Chapter III- The Flower

Transcription

1 Worksheet Class 8-Flower, Pollination and Fertilization, Ecosystem. Chapter III- The Flower 1.Name the following. a.a flower in which both male and female reproductive organs are lacking. b.the groups of secreting cells situated at the base of the pistil or on the basis of the petals. c.the structures on anthers which contain pollen grains. d.the condition of stamens when they may be free. e.the slender stalk that connects stigma to ovary. 2. Explain the following terms. a) Incomplete flower. b) Staminate flower c) Pistillate flower d) Bisexual flower e) complete flower f) Monadelphous g) Diadelphous h) Polyadelphous 3. Distinguish between the following. a) petals &petaloids b) flower& inflorescence c) petaloids&sepaloids d) polypetalous&gamopetaloous e) monoecious plants &dioecious plants f) pedicel &petiole g) Polysepalous &gamosepalous 4. Define a) Flower b) Perianth c) Hermaphrodite d) Epicalyx 5. Where are the following structures / parts located and what are their functions? a) placenta b) thalamus c) anther d) stigma e) pollen grains f) Bracts 6. Why are the following described as stated?

2 a) Maize plant as monoecious. b) Salvia sepals as petaloid c) China rose stamens as epipetaloid. 7. Match the parts in column A with the flowers or parts of flower in column B. Column A Column B a) polyadelphous i) polypetalous b) pollen grains ii) calyx, corolla c) free petals iii) nectar d) non-essential iv) bombax e) sweet fragrant fluid v) pollen sac 8. Mention if the following statements are true or false. a) Papaya is a monoecious plant. b) The prefix gamo is used whenever any of the floral whorls are fused. c) Nasturtium has nectaries. d) Stamens& carpels are the male & female parts respectively. 9. Fill in the blanks. a) The protect the young flower bud and when green they also perform photosynthesis. b) The attract insects for pollination. They also protect stamens and pistils especially when the petals form a tube. c) is the tubular slender stalk which connects the stigma to the ovary. 10. Study the diagram given below and answer the following questions. i.label the parts 1 to 8. ii.write functions of parts labeled 2 and 5 iii. Why is part labeled 1 colourful?

3 Chapter IV Pollination and Fertilization 1.Name the following a) The chief pollinating agent against the corresponding plant Dahlia Maize Vallisneria b) The parts of the ovary which give rise to Seed Fruit Fruit Wall 2. Mention True or False. If False rewrite the correct statement : a)ovary becomes a seed after fertilization. b) Outer wall of a mature pollen grain is exine. c) The interior of an ovule consists of a nutritive tissue called nucellus. d) Dahlia is an example of an insect pollinated flower. e) Zygote gives rise to an embryo. f) Dry petals may persist in some fruits. 3. Define the following terms. a) Herkogamy b) Placenta c) Double fertilization d) Dichogamy e) Protogyny f) Protandry g) Pollination h) Hydrophily i) Artificial Pollination 4. Give the location and function of the following. a) Micropyle b) Nucellus c) Ovary d) Ovule e) Integuments f) Ovary wall 5. Differentiate between the following. a) Ornithophily / Elephophily b) Entomophily / Anemophily

4 c) Herkogamy / Heterostyly d) Wind Pollinated Flowers / Insect Pollinated Flowers e) Autogamy / Allogamy f) Self pollination /Cross pollination 7.Study the diagrams given below and answer the questions that follow. a.identify the three conditions of stamens in A, B & C. b. Define the three conditions. c. Give examples for each of the conditions. 8.Give technical terms for the following a) When pollengrains of a flower reach the stigma of the same flower. b) When maturation time of reproductive parts in a flower is different. c) When stigma and anthers do not grow up to same height, which favours only cross pollination. 9.Observe the following diagram and answer the following questions. a)label the parts 1 to 6. b) What is the function of parts labeled 1,4 & 6? c) What happens to the ovule after fertilization?

5 d) Define fertilization. e) Define triple fusion 10.Describe any two contrivances in flowers which favour cross pollination 11.What are the advantages of the following in the flower to the plant concerned a) Long and feathery stigma b) Brightly coloured petals c) Smooth and light pollen d) Protruding and easily movable anthers. e) Fragrant Nectar. 12.What happens to the following after fertilization a)ovules b) Calyx 13.Match the items in column A with those in column B : Column A Column B a)generative Nucleus i)pollen Tube b)germ Pore ii)endosperm nucleus c)exine iii)testa d)secondary Nucleus iv)fertilization e)integument v)male Nuclei f)egg Nucleus vi)rough g)feathery Stigma hanging out vi)rafflesia hdifferent timing for maturation of anthers and stigma vii)insect pollination i)entomophilous viii)nasturtium j)pollination by elephant ix)wind Pollination h)flower that produces nectar x)dichogamy 14.Give scientific reasons for the following statements. a.wind pollinated flowers have long and feathery stigma. b. Pollen grains are sticky or spiny in insect pollinated flowers. c. Pollen grains are light in wind pollinated flowers.