Consideration of life on Earth should differentiate between the origin of organisms in situ and the transportation of organisms from outside with cosmic bodies in the framework of life as a widespread phenomenon of the Universe. In the case of transport of life with cosmic bodies, there are no...
The first living things on Earth were single - celled organisms. Which of the following is a characteristic of the evolution from single - celled to multi - celled organisms? A. The ability to live independently without any cooperation among cells B. The development of specialized cells for ...
Key building blocks of DNA and RNA can be made from the same raw materials. This finding suggests that instead of one or the other kick-starting life on Earth, both chemicals were involved in the first organisms. DNA and RNA are central to life. They are the molecules that ...
根据“Most organisms on Earth live on the ground or just below it.”可知,地球上的大多数生物都生活在地上或地底下。故选D。 (2)题详解: 词义猜测题。根据提示词“give plants energy.”判断,应该是将“养分”返回土壤,因此nutrients是“养分”的意思,也就是能帮助动植物生长的东西。故选C。 (3)题...
What was the first ever living thing on Earth? Some scientists estimate that 'life' began on our planet as early as four billion years ago. And the first living things weresimple, single-celled, micro-organisms called prokaryotes(they lacked a cell membrane and a cell nucleus). ...
Most organisms on the Earth live on the ground or just below it. Here, they are part of an important cycle. Plants and animals fall to the ground when they die. Later, tiny insects and other organisms break down these dead plants and animals. This process finally returns nutrients(营养物...
根据第二段第一句Most organisms on Earth live on the ground or just below it可知,正确答案为B。 (3) 细节理解题。根据第三段Then he and his team counted and photographed the organisms that lived in or moved through the cube可知,A为正确选项。 (4) 考查上下文理解。前两段都在说明微生物的重要...
Evidence suggests that microbes existed on Earth as far back as 3.7 billion years ago, a billion years after the planet formed. Animal remains, however, don't appear in the fossil record until 600 million years ago during the Ediacaran period, though there are indirect signs that animal life...
Sea Elf" (ELF members refer to themselves as "elves") claimed that by 1993 the elves had created twenty clandestine cells in England, and had used arson and other means to attack corporations in Europe and North America, including a number engaged in producing genetically modified organisms. In...