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Commac

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Biology

Topic Seven : Plant Scienc

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Seven

Quest

Student Notes

9.1 U.2 Plants transport water from the roots to the leaves to replace losses from transpiration

1. Annotate the diagram to explain how water is moving through the xylem tube from the roots to the leaf. (Slide 6)

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9.1 U.1 Transpiration is the inevitable consequence of gas exchange in the leaf

2. Define transpiration. (Slide 7)

3. Explain how the action of guard cells allows for the control of water loss. (Slide 8)

Increase water exchange loss abscisic acid levels decrease, Guard Cells fill with water and Stomata pore opens.

Decrease in Water loss

4. Draw and label open and closed guard cells (Slide 8)

9.1 U.3 The cohesive property of water and the structure of the xylem vessels allow transport under tension

5. State one property of water which allows transpiration pull to be generated. (Slide 11)

Transpiration pull utilizing capillary action

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The Meniscus

6. Water is strongly attracted to glass. How does this explain the shape of the meniscus? (Slide 10)

7. Liquid mercury, unlike water, is repelled by glass. If you filled your cylinder with mercury instead of water, what would the surface of the mercury look like? Sketch your idea next to the graduated cylinder on the previous page.

9.1 U. 4 The adhesive property of water and evaporation generate tension forces in leaf cell walls

8. Describe the journey water takes through the plant beginning at the roots. (Slide 14)

9.1 U.5 Active uptake of mineral ions in the roots causes absorption of water by osmosis.

9. Annotate the diagram below to explain the uptake of water by mineral exchange by adding K+ ‘s and H2O’s to the root hair: (Slide 15)

10. Explain why mineral ions need to be taken up by active transport in the roots. (Slide 15)

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Ions change the of concentration water from high to low concentration in the roots, water diffuses into the plant

11. State the source of energy used in active transport at the root hairs. (Slide 15)

12. What roll does fungus growing on plant root have on water uptake? (Slide 16)

9.1 A.1 Adaptations of plants in deserts and in saline soils for water conservation

11. Define xerophyte. (Slide 18)

12. Describe the reproductive adaptations of xerophytes to minimize water loss. (Slide 19)

13. Describe three physical adaptations of xerophytes to minimize water loss. (Slide 21)

14. Describe how CAM plant metabolism is an adaptation to preventing water loss. (Slide 24)

CAM:

At night CO2 is combined with (C3) to (C4). This stores the CO2 until required for photosynthesis during the day.

During the day

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9.1 S.1 Drawing the structure of primary xylem vessels in sections of stems based on microscope images

15. Draw a cross section of the xylem tube below

9.2 A.1 Structure–function relationships of phloem sieve tubes

16. Label the cross section diagram of phloem (Slide 37)

9.2 S.1 Identification of xylem and phloem in microscope images of stem and root

17. Label the cross section diagram of dicot and monocot roots and stems (Slide 38 & 39)

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9.2 U.1 Plants transport organic compounds from sources to sinks

22. The movement of materials in a plant is called (Slide 40)

23. The movement of material down from the leaves occurs in (Slide 40)

24. Distinguish between source and sink in terms of molecules in plants. (Slide 41-42)

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U.2 Incompressibility of water allows transport along hydrostatic pressure gradients .

25. Describe the effect of hydrostatic pressure (Slide 43-44)

9.2 U.3 Active transport is used to load organic compounds into phloem sieve tubes at the source

26. Explain the flow sucrose occurs from the storage cell, to the companion cells and then into the phloem. (Slides 44-45)

9.2 U.4 High concentrations of solutes in the phloem at the source lead to water uptake by osmosis

27. Why is it necessary for the veins (which contain xylem and phloem) to be relatively close together in plants? (Slide 47)

28. Describe how transpiration and osmosis help movement of sucrose in a plant. (Slides 47-48)

9.2 U.3 Active transport is used to load organic compounds into phloem sieve tubes at the source.

29. Describe how Sucrose cross the membrane in plants ((Slide 46)

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30. Outline question 28 steps using a diagram ((Slide 46)

9.2 U.5 Raised hydrostatic pressure causes the contents of the phloem to flow towards sinks.

31. Explain the mechanism for movement of sucrose during translocation (Slides 47-48)

Growing season is the leaf is the source Companion cell (with ATP) loads the sucrose into phloem Sap volume and pressure increased Unload Sap (sucrose) by the companion cell occurs at the sink (using ATP) Water flows back into the xylem Water recycles as part of transpiration

9.2 S.2 Analysis of data from experiments measuring phloem transport rates using aphid stylets and radioactively-labelled carbon dioxide

32. Describe how aphids feed (Slide 51)

33. Explain how data from radioactively-labeled carbon dioxide can be used to measure rates of phloem transport. (Slide 20-22)

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34. Draw a diagram of a dicot plant below. (Slides 57-58)

35. Draw and label diagram of a cross section of dicot stem below. (Slides 59-60)

9.3 U.1 Undifferentiated cells in the meristems of plants allow indeterminate growth.

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36. Define meristem. (Slide 61)

37. Distinguish between apical and lateral meristems in terms of location and function in the stem. (Slide 62)

38. Describe the function of the axillary bud. (Slide 65)

39. Explain where lateral meristematic growth takes place? (Slide 66)

9.3 U.2 Mitosis and cell division in the shoot apex provide cells needed for extension of the stem and development of leaves.

40. Explain why meristem cells are more likely to be in mitosis than cells found in other parts of the plant. (Slide 67)

9.3 U.3 Plant hormones control growth in the shoot apex

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41. What is a plant hormone? (Slide 68)

42. Fill in the chart below. (Slide 68)

Hormone Name Hormone ResponseAuxins

Gibberellins cell elongation + cell divisionCytokinin cell division

Abscisic acidEthylene

43. What types of physiological responses are caused by Auxin and cytokines together? (Slide 69)

44. Explain how the plant hormone Auxin effects grow in a plant cell. (Slides 71-75)

9.3 U4 Plant shoots respond to the environment by tropisms.

45. Define tropism. (Slide 76)

46. Explain, with the aid of a diagram, the role of auxins in phototropism. (Slide 77)

9.3 U.5 Auxin efflux pumps can set up concentration gradients of auxin in plant tissue.

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47. In roots, does auxin have the same or the opposite effect as auxin in shoots? (Slide 80)

48. Why has the root bent downwards in area X?

49. Why has the shoot bent upwards in area Y?

9.3 U.6 Auxin influences cell growth rates by changing the pattern of gene expression. (Slides 61-66)

In 1880, Charles Darwin did some experiments on the growth of plant shoots. These are shown in the drawings below: (Slides 81-83)

50. Describe what happened in each of these experiments.

We now know that plant hormones cause these things to happen. In experiment A, the light causes a plant hormone called auxin to move towards the darker part of the shoot.

51. Draw the pictures for experiment A, showing what happens to the auxin.

52. What effect does auxin have on the part of the shoot it moves to?

53. Why is this useful to the plant?

54. Do you think auxin is found in all parts of a shoot, or only at the tip? Use the drawings above to help with your explanation.

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55. The drawing below shows a root that has bent downwards and a shoot that has bent upwards

9.3 A.1 Micro propagation of plants using tissue from the shoot apex, nutrient agar gels and growth hormones.

56. Explain one way in which Auxin effects a change in growth in the plant in Went’s experiment. (Slides 82-83)

57. What would happen to a plant that is unable to make Auxin or contain reduced amounts of Auxin? (Slides 82-83)

9.3 A.2 Use of micropropagation for rapid bulking up of new varieties, production of virus-free strains of existing varieties and propagation of orchids and other rare species.

58. Explain the benefits to using micro propagation. (Slide 86)

9.4 U.1 Flowering involves a change in gene expression in the shoot apex

59. Describe how a change in vegetative structure occurs to create a flower. (Slide 92-94)

9.4 U.2 The switch to flowering is a response to the length of light and dark periods in many plants

60. Distinguish between long-day and short-day plants in terms of conditions required for flowering (Slide 94)

61. Define phytochrome (Slide 94)

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62. Distinguish between red light and far-red light wavelength, use the diagram as a guide. (Slide 96)

63. Use the diagram below to explain the interconversion of phytochromes between daylight and darkness (Slides 97)

64. Explain how phytochromes control flowering in short-day plants (Slide 100)

65. Explain how phytochromes control flowering in long-day plants (Slide 101)1

9.4 A.1 Methods used to induce short-day plants to flower out of season.

66. Identify factors that are changed to induce flowering. (Slide 102)

9.4 U.3 Success in plant reproduction depends on pollination, fertilization and seed dispersal

67. Describe the process of fertilization in a flowering plant (Slides 103-106)

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9.4 U.4 Most flowering plants use mutualistic relationships with pollinators in sexual reproduction

68. Describe the process of fertilization in flowering plants. (Slides107-110)

69. Explain an advantages of dispersing seeds over a wide area

9.4 S.1 Draw internal structure of seeds.

70. Draw a diagram to show the structure of a seed (Label, and include functions of, micropyle, testa, scar, radicle, plumule and seed coat) (Slide 111)

9.4 S.2 Drawing of half-views of animal-pollinated flowers. (Slide 113-115)

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Dicotyledon Seed PartsSeed Part Function

TestaCotyledon food storePlumuleMicropyle embryonic rootScar

Name Structure (Identified in with a letter a drawing on the

bottom of the page)

Function

Sepals

Petals surround the male and female flower parts

Stamen male reproductive part

Filament

Anther that contain the pollen

Pistil female reproductive part

Stigma

Style connects the stigma to the ovary

Ovaries

75. Annotate the diagram to show the metabolic processes taking place during the germination of a seed: (Slides 116-118)

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1. Water is absorbed through the micropyle2.3. Amylase hydrolyzes 4.5. Maltose is absorbed6.

9.4 S.3 Design of experiments to test hypothesis about factors affecting germination.

71. Define germination (Slide 119)

72. State the functions of the following in the germination of a seed: (Slide 119)A. WATER B. TEMPERATURE/pH C. OXYGEN

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