Read this article and write a summary. 500 to 800 words. Article 8 The 2% Differ
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Read this article and write a summary. 500 to 800 words.
Article 8 The 2% Difference Now that scientists have decoded the chimpanzee genome, we know that percent of our DNA is the same. So how can we be so different? ROBERT SAPOLSKY f you find yourself sitting close to a chimpanzee, staring that determine chimp and human brainsreasonable, at least, face to face and making sustained eye contact, something to a brainocentric neurobiologist like me. But as it turns out, interesting happens, something that is alternately moving, the chimp brain and the human brain differ hardly at all in Sewildering, and kind of creepy. When you gaze at this beast, their genetie underpinnings. Indeed, a close look at the chimp dyou suddenly realize that the face gazing back is that of a sen- genome reveals an important lesson in how genes and evolution tsent individual, who is recognizably kin. You can't help but work, and it suggests that chimps and humans are a lot more wonder, What's the matter with those intelligent design people? similar than even a neurobiologist might think Chimpanzees are close relatives to humans, but they're not e are not chimps. Chimps excel at climbing trees, but we beat them hands down at balance-beam routines: DNA, or deoxyribonucleic acid, is made up of just leotides: adenine (A), cytosine (C), eidentical to us. W four molecules, called nuc bey are covered in hair, while we have only the occasoal uanine (G), and thymine (T). The DNA codebook for every species consists of billions of these letters in a precise order. If puy with really hairy shoulders. The core differences, however, lex social when DNA is being copied in a sperm or an egg, a nucleotide is from how we use our brains. Chimps have when ves, play power politics, betray and murder each other, maketn rg the result is a mutation. If persists from generation to generation, it becomes a DNA difference-one of the many genetic distinctions that separate tools, and teach tool use across generations in a way that quali- fies as culture. They can even learn to do logic operations with symbols, and they have a relative sense of numbers. Yet those one species (chimpanzees) from another (humans). In genomes involving billions of nucleotides, a tiny 2 percent difference translates into tens of millions of ACGT differences. And that behaviors don't remotely approach the complexity and nuance of human behaviors, and in my opinion there's not the tiniest it of scientific evidence that chimps have aesthetics, spiritual 2 percent di y, or a capacity for irony or poignancy. i y opinion there's not the tiniest and chimps each have somewhere between 20,000 and 30,000 genes, so there are likely to be nucleotide differences in every single gene. What makes the human species brainy are huge numbers of standard-issue neurons. To understand what distinguishes the DNA of chimps and humans, one must first ask: What is a gene? A gene is a string of nucleotides that specify how a single distinctive protein should What accounts for those differences? A few years ago, the most ambitious project in the history ofbiology was carried out: be made. Even if the same gene in chimps and humans differs by an A here and a T there, the result may be of no consequence. Many nucleotide differences are neutral both the mutation and the sequencing of the human genome. Then just four months the normal gene cause the same protein to be made. However, a team of researchers reported that they had likewise given the right nucleotide difference between the same gene in sequenced the complete chimpanzee genome. Scientists have long known that chimps and humans share about 98 percent of heir DNA. At last, however, one can sit down with two scrolls the two species, the resulting proteins may differ slightly in con- struction and function. One might assume that the differences between chimp and of computer printout, march through the two genomes, and see human genes boil down to those sorts of typographical errors: one nucleotide being swapped for a different one and altering exactly where our 2 percent difference lies Given the outward differences, it seems reasonable to expect the gene it sits in. But a close look at the two codebooks reveals o find fundamental differences in the portions of the genome very few such instances. And the typos that do occasionallyExplanation / Answer
Chimpanzees are closest relative to the human being as they share 98% of their gene with us. Although chimpanzee looks so different from us, they can climb trees, they can jump a lot, they are full of hair, this is an unavoidable fact that human brain is far more developed than chimpanzees. The complexity and entanglement of the human brain are nowhere compared to human brain. Only 2% differences are making the biggest scene here. The present study throws light on this difference. Some years back, a group of scientists made a detailed study on the complete chimpanzee genome. A close look at the chimpanzee and human genome reveal surprising facts. DNA, deoxyribonucleic acid, is made up of four nucleotides known as adenine (A), cytosine (C), guanine (G), and thymine (T). DNA codebook for every species is made of thousands of these letters in precise orders. Mutation persists from generation to generation known as DNA difference has been one of the important criteria for differentiating species. So in genomes involving billions of nucleotides, a tiny 2% difference transforms into millions of ACGT differences. A gene is a single string of nucleotides specifying how a single distinctive protein must be made. So even if the same gene of chimpanzee and human differ in A, C, G or T, there may be no consequence. Even gene mutation, will not make any difference in transforming characters from one generation to other, in such cases. Slight difference in construction and function may happen, but that will not be responsible for the differences in the character between chimpanzee and human being.
There are no brain-specific genes that have evolved in such different directions in different species.
Neurons are basic units of the nervous system. They all look the same. They have fibrous dendrites at one end and an axonal cable at the end. Their function is also the same- transmitting the wave of excitement through channels, they have similar neurotransmitters. But the difference in species lies in the number of neurons. The human brain has 100 million times the number of neurons a sea slug’s brain has, maybe 100 million times more than the chimpanzee brain. All embryos of slug, frog, cat, chimpanzee or human firstly form a single cell committed to generating neurons. That cell divides and gives rise to two cells again the cell divides into two forming four neurons, then eight, then sixteen. This is how neurons develop by cell generation. Maybe after a dozen round of cell division, enough neurons are made for a slug. A human brain may need such 25 rounds; maybe 9 or 10 rounds of such division will form a chimpanzee brain.
So that 2% solution lies on such a simple fact. It is not the complex genome characters, but the quantity of neurons, that is responsible for the differentiation of human and chimpanzee.
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