law of segregation

简明释义

分异定律;

英英释义

例句

1.In genetics, the law of segregation 分离定律 explains how alleles separate during gamete formation.

在遗传学中，分离定律 law of segregation 解释了等位基因如何在配子形成过程中分离。

2.The law of segregation 分离定律 is crucial for understanding inheritance patterns in organisms.

理解生物体的遗传模式时，分离定律 law of segregation 是至关重要的。

3.Teachers often explain the law of segregation 分离定律 using simple Mendelian traits.

老师们常常用简单的孟德尔性状来解释分离定律 law of segregation。

4.The law of segregation 分离定律 states that each individual carries two alleles for each trait.

分离定律 law of segregation 表示每个个体对每种性状携带两个等位基因。

5.In a Punnett square, the law of segregation 分离定律 helps predict the genotypes of offspring.

在潘尼特方格中，分离定律 law of segregation 有助于预测后代的基因型。

作文

The concept of the law of segregation is fundamental in the field of genetics and was first proposed by Gregor Mendel in the 19th century. This principle states that during the formation of gametes, the alleles for a trait separate so that each gamete carries only one allele for each gene. This separation is crucial for understanding how traits are inherited from parents to offspring.To illustrate this concept, consider a simple example involving pea plants, which Mendel famously used in his experiments. If we take a plant that is homozygous for a trait, such as flower color—let's say purple (PP)—and cross it with a plant that is homozygous for the opposite trait, white (pp), the offspring will all be heterozygous (Pp) and display the dominant trait, purple flowers. However, when these heterozygous plants reproduce, the law of segregation comes into play. During gamete formation, the alleles segregate, resulting in gametes that carry either the dominant allele (P) or the recessive allele (p).When these gametes combine during fertilization, the offspring can inherit various combinations of alleles: PP, Pp, or pp. According to the law of segregation, the phenotypic ratio of the offspring will typically follow a predictable pattern, often a 3:1 ratio of dominant to recessive traits in a monohybrid cross, assuming complete dominance.Understanding the law of segregation is not only important in genetics but also has broader implications in fields such as medicine, agriculture, and evolutionary biology. For instance, in medical genetics, this principle helps explain the inheritance patterns of genetic disorders. If a recessive disorder is carried by both parents, the law of segregation predicts that there is a 25% chance that their child will inherit the disorder if both parents are carriers.In agriculture, the law of segregation plays a vital role in plant breeding. By understanding how traits are passed down through generations, farmers can select for desirable characteristics, such as drought resistance or increased yield. This selective breeding relies heavily on the principles established by Mendel, demonstrating the practical applications of the law of segregation in improving crop varieties.Moreover, the law of segregation contributes to our understanding of biodiversity. The genetic variation resulting from the segregation of alleles during reproduction is a driving force behind evolution. It allows populations to adapt to changing environments, as different combinations of alleles may confer advantages in survival and reproduction.In conclusion, the law of segregation is a cornerstone of genetic theory that explains how traits are inherited through the separation of alleles during gamete formation. Its implications extend far beyond the laboratory, influencing fields such as medicine, agriculture, and evolutionary biology. By grasping the significance of the law of segregation, we can better understand the complexities of inheritance and the biological processes that shape the living world around us.

分离定律的概念在遗传学领域中是基础性的，最早由格里戈尔·孟德尔在19世纪提出。这个原则表明，在配子形成过程中，性状的等位基因会分开，从而使每个配子只携带每个基因的一个等位基因。这种分离对于理解特征是如何从父母遗传给后代至关重要。为了说明这一概念，可以考虑一个简单的例子，涉及豌豆植物，孟德尔在他的实验中著名地使用了这些植物。如果我们取一株对某个性状是纯合子的植物，比如花色——假设是紫色（PP）——并与一株对立性状的纯合子植物，即白色（pp）进行交配，那么所有的后代将都是杂合子（Pp），并表现出显性性状，即紫色花。然而，当这些杂合植物繁殖时，分离定律开始发挥作用。在配子形成过程中，等位基因分开，产生的配子只携带显性等位基因（P）或隐性等位基因（p）。当这些配子在受精过程中结合时，后代可以继承不同的等位基因组合：PP、Pp或pp。根据分离定律，后代的表型比例通常会遵循可预测的模式，通常在单基因杂交中表现为显性与隐性性状的3:1比例，假设完全显性。理解分离定律不仅在遗传学中重要，还在医学、农业和进化生物学等领域具有更广泛的意义。例如，在医学遗传学中，这一原则有助于解释遗传疾病的遗传模式。如果两位父母都携带一种隐性疾病，则分离定律预测他们的孩子有25%的机会遗传该疾病，前提是两位父母都是携带者。在农业中，分离定律在植物育种中起着至关重要的作用。通过理解性状是如何在几代人之间传递的，农民可以选择出理想的特征，如抗旱性或产量增加。这种选择性育种在很大程度上依赖于孟德尔建立的原则，展示了分离定律在改良作物品种方面的实际应用。此外，分离定律有助于我们理解生物多样性。由于在繁殖过程中等位基因的分离所导致的遗传变异是进化的推动力。它使得种群能够适应环境的变化，因为不同的等位基因组合可能赋予生存和繁殖上的优势。总之，分离定律是遗传理论的基石，解释了在配子形成过程中等位基因的分离如何影响性状的遗传。其影响远不止于实验室，影响着医学、农业和进化生物学等领域。通过掌握分离定律的重要性，我们可以更好地理解遗传的复杂性以及塑造我们周围生物世界的生物过程。