2023届高三英语二轮复习外刊阅读语法填空2专练

高考外刊语法填空2 第一篇 It is one of the defining attributes of being human: when 1 (compare) with our closest primate relatives, we have incredibly large brains. Now scientists 2（shed）light on the reasons for the difference by collecting cells from humans, chimps and gorillas and turning them into lumps of brain in the laboratory.   Tests on the tiny” brain organoids reveal a hitherto unknown molecular switch that 3 (control) brain growth and makes the human organ three times larger than brains in the great apes. Tinker 4 the switch and human brain loses its growth advantage, while great ape brain can be made to grow more like that in the human.  “5 we see is a difference in cellular behavior very, very early on that 6 (allow) the human brain to grow larger,” said Dr Madeleine Lancaster of the Medical Research Councils Laboratory of Molecular Biology in Cambridge.” We are able to account for almost all of the size difference.” The healthy human brain typically reaches about 1,500cc in adulthood, roughly three times the size of the gorilla brain, at 500cc, 7 the chimp brain at 400cc.But working out why has been difficult, not least because 8____(develop) human and great ape brains cannot easily be studied. Lancaster and her colleagues collected cells, often left over from medical tests or operations, 9 humans, gorillas and chimps, and reprogrammed them into stem cells. They then grew these cells, in a study published in Cell, encouraging them to turn into brain organoids--little lumps of brain tissue a few millimetres wide.   Weeks later, the human brain organoids were by far the largest, and close examination revealed 10 . In human brain tissue, so-called neural progenitor cells--which go on to make all of the cells in the brain--divided more than those in great ape brain tissue. Mathematical modelling showed the difference happens so early on in brain development that it leads to a near doubling in the number of neurons in the adult human cerebral c