文章列表

• 1.【英语时差8,16】动物界的染色体有何不同？
• In mammals, the sex of a baby is determined by the combination of chromosomes it inherits from its parents. Nearly every cell in a male body has two d...
• 2.【英语时差8,16】如何界定性别？2
• Another sexual difference among mammals that doesnt hold with other animals is size. In most mammals the male is larger than the female, but in most o...
• 3.【英语时差8,16】什么是卟咻症？2
• In this form of hereditary porphyria, the skin becomes white with anemia and very sensitive to light. (Remember that vampires only come out at night.)...
• 4.【英语时差8,16】什么是卟咻症？
• The vampire is the stuff of the great horror stories. However, a recent textbook by geneticist John Jenkins suggests that Bram Stokers legend of the v...
• 5.【英语时差8,16】抗生素历史2
• Since that time, scientists have found that numerous species of fungi produce chemicals to destroy bacteria and that bacteria even produce chemicals t...
• 6.【英语时差8,16】抗生素历史
• When you take an aspirin, a decongestant, or a muscle relaxant, the drug youre taking was probably made by a chemist combining a specific mixture of c...
• 7.【英语时差8,16】土星上真的有生命存在？
• Acetylene and hydrogen molecules are disappearing from the atmosphere of Saturns moon, Titan. Its a mystery befitting Sherlock Holmes investigative sk...
• 8.【英语时差8,16】伽利略—现代科学之父2
• Galileo, however, used one of the earliest telescopes to look at Jupiter. He noticed that Jupiter has moons going around it. Apparently everything in ...
• 9.【英语时差8,16】伽利略—现代科学之父
• What makes Galileo a science hero? For one thing, he moved human knowledge forward against outstanding prejudice and even persecution. Back in 1616, w...
• 10.【英语时差8,16】微波炉如何加热食物？2
• Microwaves heat water by jerking the water molecules around, so to speak. Each water molecule has a slight positive electric charge on one side and a ...