问题详情
共用题干
Keeping Cut Flowers（鲜切花）
1. While everybody enjoys fresh cut flowers around his/her house,few people know how to keep them for as long as possible .This may be done by keeping in mind a few simple facts.
2. An important thing to remember about cut flowers is that they are sensitive to temperature.For example,studies have shown that cut carnations（康乃馨）retain their freshness eight times lon-ger when kept at 12℃than when kept at 26℃．Keeping freshly harvested flowers at the right tem-peratures is probably the most important aspect of flower care.
3. Flowers are not intended by nature to live very long.Their biological purpose is simply to at-tract birds or insects,such as bees,for pollination（授粉）.After that,they quickly dry up and die. The process by which flowers consume oxygen and produce carbon dioxide（二氧化碳）, called respiration（呼吸）,generates the energy the flower needs to give the flower its shape and color. The making of seeds also depends on this energy.While all living things respire,flowers have a high level of respiration.A result of all this respiration is heat,and for flowers the level of heat relative to the mass of the flower is very high.Respiration also brings about the eventual death of the flower. Thus the greater the level of respiration,the sooner the flower dies.
4. How,then,to control the rate at which flowers die?By controlling respiration.How is respi-ration controlled?By controlling temperature .We know that respiration produces heat,but the re-verse（相反的过程）is also true. Thus by maintaining low temperatures , respiration is reduced and the cut flower will age more slowly.
5. Another vital factor in keeping cut flowers is the quality of the water in which they are placed. Flowers find it difficult to“drink”water that is dirty or otherwise polluted.Even when water looks and smells clean,it almost certainly contains harmful substances that can endanger the flowers. To rid the water of these unwanted substances, household chlorine bleach（漂白剂）can be used in small quantities.It is recommended that 15 drops of chlorine bleach(at 4%solution)be add-ed to each litre of water. The water and solution should also be replaced each day.
Paragraph 2________
A: Control of Respiration
B: Beauty of Fresh Cut Flowers
C: Role of Respiration
D: Most Important Aspect of Flower Care
E: Need for Cleanwater
F:.Ways of Stopping Respiration
相关标签： 鲜切花 漂白剂 康乃馨 二氧化碳
未找到的试题在搜索页框底部可快速提交，在会员中心"提交的题"查看可解决状态。
收藏该题
查看答案
相关问题推荐
-
修剪在鲜切花生产中的作用为（）。
A、控制植物大小
B、更新复壮
C、调节花期
D、降低病虫危害
-
玫瑰象征爱情，虽然只是蔷薇属的一个种，一年只开一次花，但是是世界上重要的鲜切花。
A、对
B、错
-
作为一般生态规律，越是耐寒的鲜切花越不耐热，越是耐热的鲜切花越不耐寒。
A、对
B、错
-
在微波炉清洁剂中加入漂白剂，就会释放出氯气；在浴盆清洁剂中加入漂白剂，也会释放出氯气；在排烟机清洁剂中加入漂白剂，没有释放出任何气体。现有一种未知类型的清洁剂，加入漂白剂后，没有释放出氯气。根据上述实验，以下哪项关于这种未知类型的清洁剂的断定一定为真？
Ⅰ．它是排烟机清洁剂。
Ⅱ．它既不是微波炉清洁剂，也不是浴盆清洁剂。
Ⅲ．它要么是排烟机清洁剂，要么是微波炉清洁剂或浴盆清洁剂。
A．仅Ⅰ。
B．仅Ⅱ。
C．仅Ⅲ。
D．仅Ⅰ和Ⅱ。 -
(飞机O~l摄氏度机械分级干燥剂埋没干燥法水漫斑温水脱涩法一1~O摄氏度人工分级混果法压花干燥法)
11.填写下列水果和蔬菜的最适贮藏温度:菜花();葡萄()。
12.水果和蔬菜的冷害症状有()、凹陷、不能正常成熟、褐变、腐烂等。
我国目前鲜切花长距离运输主要采用()运输，这样运输速度快，时间较短。花材干燥的常用方法有()、自然风干燥法、()、液剂浸渍法和调节温度与空气压力干燥法。园产品分级可采用()和()。柿子脱涩常用的方法有()、二氧化碳法、()、乙烯脱涩法、乙烯利脱涩法、酒精脱涩法和石灰水脱涩法等。