2023届高考英语三轮复习冲刺押题外刊阅读理解训练 (12)

2023届高考英语三轮复习·冲刺押题 外刊阅读理解训练12 ——改编自Why Even Identical Twins Have Different Fingerprints 【文章】 Fingerprints are a universal trait found in every human being. Each individual has a unique set of fingerprints that can be distinguished from one another, even between identical twins. While the basic design of finger ridges is determined by genetics, environmental factors also play a role in shaping an individual's fingerprints. The sensitivity of human skin to environmental stimuli such as sunlight highlights the vulnerability of our skin to external influence. This sensitivity begins during fetal development, where friction ridges form when the outside and inside layers of skin come together. Although the basic structure of fingerprints stems from the baby's inherited genes, the direction, spacing, and size of ridges can vary due to fetal cell growth rates, movement, nutrient intake, and womb environment. The formation of a fetus's fingertips occurs between 13 and 19 weeks of gestation. During this time, a child's fingerprints may be influenced by their position in the uterus, rubbing against the umbilical cord or womb walls. To put it into perspective, a change in pressure on the fingers can cause alterations in fingerprint patterns. Once a fingerprint is developed, it remains static throughout one's life. Besides environmental influences, genetic mutations can also result in distinct fingerprint designs, even among identical twins. Genes act like pathways that enable communication between cells and carry out instructions. Yet, each person's genetic pathways and signals are unique, resulting in differences in their fingerprints. The uniqueness of everyone's fingerprints makes them crucial in forensic science, as they have been used to help solve crimes for over a century. Fingerprints not only serve as a source of identification but also assist in tracing criminal activities and solving mysteries. Additionally, with the advent of fingerprint biometrics, it has become