tailieunhanh - Environmental Pollution Control Microbiology - Chapter 5

Tảo là các vi sinh vật quang hợp có chứa chất diệp lục. Họ có thể là một tế bào hoặc multicell, có thể cử động dể dàng hoặc không-có thể cử động dể dàng. Tảo sử dụng ánh sáng như là nguồn năng lượng để tổng hợp tế bào và các ion vô cơ như là nguồn của các hóa chất cho tế bào nguyên sinh vật. Chúng được tìm thấy có một số tiền hợp lý của các yếu tố ánh sáng và chất dinh dưỡng. Tảo có cả tích cực và tác động tiêu cực đến môi. | Chapter 5 ALGAE Algae are photosynthetic microorganisms containing chlorophyll. They can be single cell or multicell motile or non-motile. Algae use light as their source of energy for cell synthesis and inorganic ions as their source of chemicals for cell protoplasm. They are found where there is a reasonable amount of light and nutrient elements. Algae have both a positive and a negative impact on the envfronment. One of the positive aspects of algae is the production of oxygen in proportion to the growth of new cells. On the negative side algae are responsible for tastes and odors in many surface water supplies. Algae also take stable inorganic ions and convert them into organic matter that ultimately must be stabilized. The new organic matter can be used as a source of nutrients for both plants and animals. Unfortunately stabilization of dead algae uses most of the oxygen produced during growth. DESCRIPTION Like fungi algae are identified by their physical characteristics. The primary characteristic of algae is pigmentation. Colors range from green to yellow-green to brown to red. Algae are larger than bacteria and can be easily seen and identified by microscopic examination at 100 X magnification. Like fungi the algae have a clearly defined nucleus and are classified as Eucarya. The filamentous algae resemble fungi with photosynthesis providing the major Copyright 2004 by Marcel Dekker Inc. All Rights Reserved. difference between these two groups of microorganisms. Most of the filamentous algae are larger than fungi. Some of the motile algae resemble protozoa. The single cell motile algae look like green flagellated protozoa. Current classification systems used to group microorganisms are arbitrary systems that do not delineate all the differences in the organisms. Transition organisms fall between two groups instead of being clearly defined by any one group. The lack of a defined nucleus caused a change in the classification of the blue-green microorganisms .