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Tham khảo tài liệu '21st century manufacturing episode 2 part 10', kỹ thuật - công nghệ, cơ khí - chế tạo máy phục vụ nhu cầu học tập, nghiên cứu và làm việc hiệu quả | 374 Biotechnology Chap. 9 Additionally enzymes can be produced synthetically and are used in everyday situations for example in laundry detergents to break down proteins that may have been spilled on clothing. 9.5.4 The Genome and Chromosomes The genome is the complete genetic information or total DNA content of an organism. It is packaged into chromosomes which are genetic structures consisting of tightly coiled threads of deoxyribonucleic acid DNA and associated proteins. The genome functions as a blueprint for making an organism. It contains all instructions for building cell structures and directing life processes throughout the lifetime of the organism. Different organisms have different numbers of chromosomes per nucleus. Humans have 46 chromosomes arranged in 22 pairs plus XX or XY except in the sperm or the egg which has 22 chromosomes plus X or Y. The nuclei of most human cells contain two sets of chromosomes each set contributed by one parent. Chromosomes can be observed under a microscope when stained with certain dyes they reveal a distinctive pattern of light and dark bands. In karyotype analysis observable differences in size and banding patterns distinguish the chromosomes from one another. It is also possible to detect major chromosomal abnormalities such as that of Down s syndrome in which there is an extra copy of chromosome 21. 9.5.5 DNA Deoxyribonucleic Acid as the Carrier of Genetic Information The science and engineering of deoxyribonucleic acid DNA are central to most biotech industrial processes. Why is DNA so special The answer is that DNA is the genetic material for probably all living organisms.4 It should be pointed out that some viruses use RNA rather than DNA as their genetic material. Specifically DNA carries the genetic information that is vital for the cells in a person s body to grow function and divide normally. Thus DNA has a universal role in defining and regulating life on the planet from simple bacteria to complex organisms .