cytosine

简明释义

英[ˈsaɪtəsɪn]美[ˈsaɪtoʊˌsin]

n. [生化] 胞嘧啶；胞核嘧啶

英英释义

单词用法

同义词

反义词

例句

1.Cytosine organic compound of the pyrimidine family often called a base consisting of a single ring containing both nitrogen and carbon atoms and an amino group.

胞嘧啶：嘧啶族的有机化合物。常被称为基，包含一个单环，内有氮原子和碳原子，还有氨群。

2.The methyl groups are attached only to specific cytosine bases - one of the four building blocks of DNA.

这些甲基团只粘附于特定胞嘧啶碱基- DNA四个组成成分之一。

3.What relative proportions of adenine, guanine, thymine, and cytosine would you expect to find in the two DNA samples? What assumptions have you made?

在这两个DNA样品中腺嘌呤、鸟嘌呤、胞嘧啶、胸腺嘧啶之间的相互比例存在怎样的关系？

4.In certain bacteriophages, 5 - methylol cytosines have substituted for the cytosine. In the late 40s, looks up Garv e.

在某些噬菌体中，5-羟甲基胞嘧啶取代了胞嘧啶。40年代后期，查加夫。

5.Methods Cidofovir was synthesized via 6-step reactions with cytosine as the starting material.

方法以胞嘧啶为起始原料，经六步反应合成西多福韦。

6.A white, crystalline nucleoside, C9H13N3O5, composed of one molecule each of cytosine and ribose.

胞苷一种白色的晶状核苷，c9h13n3o5，由每个。

7.Nucleotide N9705 produced by a strain of Streptomyces is a ramification of peptide acyl cytosine nucleotides that has a wide range of antibiotic activities.

由一株链霉菌产生的核苷N970 5是肽酰胞嘧啶核苷衍生物，具有广谱抗生活性。

8.RNA could intensify the inhibitory effect of homoharringtonine and low-dose of arabinsyl cytosine on the cell proliferation of K562 cells.

RNA能增强高三尖杉酯碱联合小剂量阿糖胞苷对K562细胞增殖的抑制作用。

9.The DNA sequence contains a high proportion of cytosine (胞嘧啶) compared to adenine.

DNA序列中包含的胞嘧啶(cytosine)比例高于腺嘌呤。

10.Mutations in the cytosine (胞嘧啶) base can lead to genetic disorders.

在胞嘧啶(cytosine)碱基中的突变可能导致遗传疾病。

11.In RNA, cytosine (胞嘧啶) pairs with guanine instead of thymine.

在RNA中，胞嘧啶(cytosine)与鸟嘌呤配对，而不是胸腺嘧啶。

12.The presence of cytosine (胞嘧啶) is crucial for proper DNA replication.

存在胞嘧啶(cytosine)对于正确的DNA复制至关重要。

13.Researchers found that cytosine (胞嘧啶) methylation plays a role in gene expression regulation.

研究人员发现胞嘧啶(cytosine)甲基化在基因表达调控中起着重要作用。

作文

In the vast and intricate world of molecular biology, the study of DNA and its components is fundamental to understanding life itself. One of the key players in this complex narrative is a nucleobase known as cytosine, which plays a crucial role in the structure of DNA. To fully appreciate the significance of cytosine, we must first delve into the basic structure of DNA. DNA, or deoxyribonucleic acid, is composed of two strands that coil around each other to form a double helix. These strands are made up of a sugar-phosphate backbone and nitrogenous bases that pair with one another to create the rungs of the helix. The four main nitrogenous bases in DNA are adenine, thymine, guanine, and cytosine. Each of these bases has unique properties and functions, but cytosine stands out for its ability to form hydrogen bonds with guanine, ensuring the stability of the DNA structure. Cytosine is classified as a pyrimidine base, which means it has a single-ring structure. This structural characteristic allows cytosine to fit snugly between the two strands of DNA, contributing to the overall stability of the double helix. The pairing of cytosine with guanine is essential not only for maintaining the integrity of the genetic code but also for facilitating the processes of replication and transcription. During DNA replication, the strands separate, and new complementary bases are added to each strand. The presence of cytosine ensures that the correct genetic information is passed on to new cells, which is vital for growth and development. Moreover, cytosine is not just a passive participant in the structure of DNA; it also plays an active role in gene regulation. Methylation of cytosine residues can affect gene expression, turning genes on or off without altering the underlying DNA sequence. This process is crucial for cellular differentiation and the proper functioning of organisms. For example, in mammals, methylation patterns of cytosine can influence whether a cell becomes a muscle cell, a nerve cell, or any other type of cell. As such, understanding cytosine and its modifications is key to unraveling the complexities of epigenetics. In addition to its biological significance, cytosine has implications in the field of medicine. Variations in cytosine sequences can lead to genetic disorders, and researchers are continually exploring the connections between cytosine methylation patterns and diseases such as cancer. By studying how cytosine behaves in different contexts, scientists hope to develop targeted therapies that can correct or mitigate the effects of these genetic variations. In conclusion, cytosine is much more than just a building block of DNA; it is a vital component that influences genetic stability, regulates gene expression, and holds potential for medical advancements. As research continues to evolve, our understanding of cytosine will undoubtedly deepen, revealing even more about the intricate dance of life at the molecular level. By appreciating the role of cytosine within the broader context of genetics and biology, we can gain insights into the very essence of what it means to be alive.

在分子生物学的广阔而复杂的世界中，DNA及其组成部分的研究是理解生命本身的基础。一个在这个复杂叙事中扮演关键角色的核苷酸是被称为胞嘧啶的核苷碱基，它在DNA结构中发挥着至关重要的作用。要充分理解胞嘧啶的重要性，我们必须首先深入了解DNA的基本结构。DNA，即脱氧核糖核酸，由两条相互缠绕形成的双螺旋构成。这些链由糖磷酸骨架和氮碱基组成，后者彼此配对以形成螺旋的梯级。DNA中的四种主要氮碱基是腺嘌呤、胸腺嘧啶、鸟嘌呤和胞嘧啶。这些碱基各有独特的性质和功能，但胞嘧啶因其能够与鸟嘌呤形成氢键而突出，从而确保DNA结构的稳定性。 胞嘧啶被归类为嘧啶碱基，这意味着它具有单环结构。这一结构特征使得胞嘧啶能够紧密地嵌入DNA的两条链之间，从而有助于双螺旋的整体稳定性。胞嘧啶与鸟嘌呤的配对不仅对维持遗传密码的完整性至关重要，而且还促进了复制和转录过程。在DNA复制过程中，链会分开，并向每条链添加新的互补碱基。胞嘧啶的存在确保了正确的遗传信息被传递到新细胞中，这对于生长和发育至关重要。 此外，胞嘧啶不仅是DNA结构中的被动参与者；它还在基因调控中发挥着积极作用。胞嘧啶残基的甲基化可以影响基因表达，在不改变基础DNA序列的情况下打开或关闭基因。这个过程对细胞分化和生物体的正常功能至关重要。例如，在哺乳动物中，胞嘧啶的甲基化模式可以影响细胞是成为肌肉细胞、神经细胞还是其他类型的细胞。因此，理解胞嘧啶及其修饰对于揭示表观遗传学的复杂性至关重要。 除了其生物学意义外，胞嘧啶在医学领域也有重要意义。胞嘧啶序列的变异可能导致遗传疾病，研究人员不断探索胞嘧啶甲基化模式与癌症等疾病之间的联系。通过研究胞嘧啶在不同背景下的表现，科学家希望开发针对性的治疗方法，以纠正或减轻这些遗传变异的影响。 总之，胞嘧啶不仅仅是DNA的构建块；它是影响遗传稳定性、调节基因表达并对医学进步具有潜力的重要组成部分。随着研究的不断发展，我们对胞嘧啶的理解无疑将加深，揭示出更多关于分子层面上生命复杂舞蹈的奥秘。通过在更广泛的遗传学和生物学背景下欣赏胞嘧啶的角色，我们可以获得对生命本质的深刻见解。