Unit 5 Biology

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39) Name the specific type of plant tissue or cell that performs the following functions:

a) waterproofing the surface layer

Endodermos

b) rapidly dividing into new cells

Mitosis

c) transporting sugars throughout the plant

Phloem

40)Maple syrup is produces from the sap moving in the xylem of maple trees in the early spring. How would taking too much sap in the spring harm the maple tree?

That sap is an energy store to give it a strong start in spring. If you take too much, that is less energy for the tree to use.

41) A number of plants are currently being stydies for use in cleaning up land sites contanining toxic substances.

a)name the technique of using plants for this purpose

Phytoremediation

b)describe one way plants can clean up toxic substances

Phytoextraction (or phytoaccumulation) uses plants or algae to remove contaminants from soils, sediments or water into harvestable plant biomass (organisms that take larger-than-normal amounts of contaminants from the soil are called hyperaccumulators). Phytoextraction has been growing rapidly in popularity worldwide for the last twenty years or so. In general, this process has been tried more often for extracting heavy metals than for organics. At the time of disposal, contaminants are typically concentrated in the much smaller volume of the plant matter than in the initially contaminated soil or sediment. 'Mining with plants', or phytomining, is also being experimented with. The plants absorb contaminants through the root system and store them in the root biomass and/or transport them up into the stems and/or leaves. A living plant may continue to absorb contaminants until it is harvested. After harvest, a lower level of the contaminant will remain in the soil, so the growth/harvest cycle must usually be repeated through several crops to achieve a significant cleanup. After the process, the cleaned soil can support other vegetation.

c) list two advantages and two disadvantages of this technique.

Advantages: The main advantage of phytoextraction is environmental friendliness. Traditional methods that are used for cleaning up heavy metal-contaminated soil disrupt soil structure and reduce soil productivity, whereas phytoextraction can clean up the soil without causing any kind of harm to soil quality. Another benefit of phytoextraction is that it is less expensive than any other clean-up process. Disadvantages: As this process is controlled by plants, it takes more time than anthropogenic soil clean-up methods.

42) a) Is the plant an angiosperm or a gymnosperm? Explain.

b) Based on these five features, explain whether you think it came from a desert island or a tropical rainforest jungle.

see its an angiospermic plant and it is a mono cot which is a sub type of angiospremic plant and it is a desert plant because the tough waxy epidemal cells are there in desert plant only!! The

epidermis serves several functions, it protects against water loss, regulates gas exchange, secretes metabolic compounds, and (especially in roots) absorbs water and mineral nutrients. Woody stems and some other stem structures produce a secondary covering called the periderm that replaces the epidermis as the protective covering. An angiospermic plant has a taproot !!

43) State three reason the rate of climate change could be reduced by protecting large areas of natural forests in Canada.

1) The exchange of C02 into Oxygen would continue to happen. 2) Wildlife species would be preserved 3) The trees provide stabilization for the ground underneath. If you were to clearcut the forests, there would be flooding downhill, and huge amounts of erosion,

44) Describe three ways human activities affect soil in urban environments.

45) a) explain how the solution ranked in relation to the other two;

b) state the evidence that supports your answer, and

c) explain why the plant grew the way it did

46) What plant structures does each of...
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