Part I: Background: Tianjin, heavy metal pollution and the impact of chlorophyll, Arabidopsis Introduction
Part II: Implementation part: planting, water preparation, treatment, determination of chlorophyll
Part III: Summary: Arabidopsis thaliana under heavy metal pollution, changes in chlorophyll content and the subject of significance
4 selected as the test material in Arabidopsis
Biologists selected species through scientific research, to reveal a universal law of life phenomena, this time, this species is that the selected model organisms. Is a cruciferous plant Arabidopsis thaliana, widely used in plant genetics, developmental biology and molecular biology, has become a typical pattern of plants, mainly due to the plant based on the following features:
(1) plant morphology small size, height of only 30cm or so, a good cup for planting trees;
(2) fast growth cycle, every generation time is short, generally from seed sowing to harvest only about 6 weeks;
(3) seed number per plant per generation can produce thousands of seeds;
(4) morphological characteristics of simple, vitality, can be made with ordinary artificial culture medium;
(5) genome is small, only 5 pairs of chromosomes.
Part II: Implementation: Testing of heavy metal ions with different concentrations of sewage on the chlorophyll content of Arabidopsis thaliana, provide the basis for wastewater treatment. (Query metal ions Cd, Pb and Cu content in the water allowed)
】 【Equipment and reagents
Arabidopsis seeds, flower pots, nourishment soil, spectrophotometer, centrifuges, scales, scissors, mortar, funnel, pipette, beaker, acetone, quartz sand, Cd (NO2) 2, Pb (NO2) 2, Cu (NO2) 2, distilled water
An Arabidopsis plant:
Select absorbent, soft soil nutritive soil as planting soil in Arabidopsis. 9cm in diameter pot, the pot planting 20-30 teeth. After sowing in pots on the cast film, the growth of a plant to provide a moist environment. Sprouting in the fifth day, when about to grow in the fourth week after the third film leaves began to experiment.
2, preparation of sewage containing heavy metal ions
Preparation containing Cd (NO3) 2, Pb (NO3) 2, Cu (NO3) 2 solution, respectively, to contain Cd2 +, Pb2 +, Cu2 + ion concentration of 5mg / L, 25mg / L, 50mg / L, 100mg / L
(Written in some detail the process of their translation into English.)
3 changes of chlorophyll content: solution treated with different concentrations of Arabidopsis
To the cultivation of Arabidopsis thaliana were added to pots containing three different concentrations of heavy metals 5mg / L, 25mg / L, 50mg / L, 100mg / L of sewage 30mL, Arabidopsis heavy metal ion contamination of low concentration to a certain extent patience, but as time increases, the toxic effects gradually increased, decreased chlorophyll content, growth was inhibited. The results showed that treatment with different concentrations of heavy metals, the Arabidopsis chlorophyll content did not change on day 1, followed by 3 days the chlorophyll content of the change (decrease) compared with the control group reached a significant level, especially the first 4 days , chlorophyll content increased with increasing concentration of Cd decreased significantly.