dark reaction

简明释义

暗反应

英英释义

例句

1.Without the dark reaction 暗反应, plants would not be able to convert carbon dioxide into glucose.

没有暗反应 暗反应，植物将无法将二氧化碳转化为葡萄糖。

2.The Calvin cycle is an example of a dark reaction 暗反应 in photosynthesis.

卡尔文循环是光合作用中一个暗反应 暗反应的例子。

3.In the chloroplasts, the dark reaction 暗反应 occurs in the stroma.

在叶绿体中，暗反应 暗反应发生在基质中。

4.The process of photosynthesis includes both light-dependent reactions and dark reaction 暗反应.

光合作用包括光依赖反应和暗反应 暗反应。

5.The dark reaction 暗反应 utilizes ATP and NADPH produced during the light reactions.

暗反应 暗反应利用光反应中产生的ATP和NADPH。

作文

Photosynthesis is a vital process that sustains life on Earth, allowing plants to convert sunlight into energy. This complex process can be divided into two main stages: the light-dependent reactions and the light-independent reactions, commonly known as the dark reaction. The dark reaction does not occur in complete darkness but rather takes place in the absence of direct sunlight. It primarily occurs in the stroma of chloroplasts, where the energy produced during the light-dependent reactions is utilized to synthesize glucose from carbon dioxide and water.The light-dependent reactions capture solar energy and convert it into chemical energy in the form of ATP and NADPH. These molecules serve as energy carriers that fuel the subsequent dark reaction. During this stage, the energy stored in ATP and NADPH is used to drive the conversion of carbon dioxide into organic compounds through a series of enzymatic reactions. One of the most crucial pathways involved in the dark reaction is the Calvin cycle, which was named after the scientist Melvin Calvin, who elucidated this process.In the Calvin cycle, carbon dioxide is fixed into a five-carbon sugar molecule called ribulose bisphosphate (RuBP) by the enzyme RuBisCO. This reaction produces a six-carbon intermediate that quickly splits into two three-carbon molecules known as 3-phosphoglycerate (3-PGA). These molecules are then phosphorylated by ATP and reduced by NADPH, resulting in the formation of glyceraldehyde-3-phosphate (G3P), a three-carbon sugar that can be converted into glucose and other carbohydrates.The dark reaction plays a crucial role in the overall process of photosynthesis, as it is responsible for synthesizing the carbohydrates that provide energy for the plant and, ultimately, for all organisms that rely on plants for food. Without the dark reaction, the energy captured during the light-dependent reactions would not be transformed into a stable form that can be used by living organisms.Moreover, the efficiency of the dark reaction can be influenced by various factors, including temperature, the concentration of carbon dioxide, and the availability of ATP and NADPH. For instance, high temperatures can lead to increased rates of photorespiration, a process that competes with the Calvin cycle and reduces the overall efficiency of photosynthesis.In conclusion, the dark reaction is an essential component of photosynthesis that enables plants to convert inorganic carbon sources into organic compounds. By understanding the mechanisms behind the dark reaction, we gain insight into how plants contribute to the Earth's ecosystem and how they support life by providing oxygen and food. This knowledge is particularly important in the context of global challenges such as climate change and food security, as enhancing the efficiency of photosynthesis could play a significant role in sustainable agriculture and environmental conservation.

光合作用是维持地球生命的重要过程，使植物能够将阳光转化为能量。这个复杂的过程可以分为两个主要阶段：光依赖反应和光独立反应，通常称为暗反应。暗反应并不是在完全黑暗中进行，而是在没有直接阳光的情况下进行。它主要发生在叶绿体的基质中，在那里，光依赖反应中产生的能量被用于将二氧化碳和水合成葡萄糖。光依赖反应捕获太阳能，并将其转化为化学能，以ATP和NADPH的形式储存。这些分子作为能量载体，为随后的暗反应提供动力。在这一阶段，ATP和NADPH中储存的能量被用于通过一系列酶促反应驱动二氧化碳转化为有机化合物。其中一个涉及暗反应的关键途径是卡尔文循环，这个名称源于科学家梅尔文·卡尔文，他阐明了这一过程。在卡尔文循环中，二氧化碳通过酶RuBisCO固定到一种叫做核酮糖二磷酸（RuBP）的五碳糖分子上。这一反应产生一个六碳中间体，该中间体迅速分裂成两个三碳分子，称为3-磷酸甘油酸（3-PGA）。这些分子随后被ATP磷酸化，并被NADPH还原，最终形成甘油醛-3-磷酸（G3P），一种可以转化为葡萄糖和其他碳水化合物的三碳糖。暗反应在光合作用的整体过程中发挥着至关重要的作用，因为它负责合成为植物提供能量的碳水化合物，并最终为所有依赖植物食物的生物提供能量。如果没有暗反应，在光依赖反应中捕获的能量将无法转化为生物体可以使用的稳定形式。此外，暗反应的效率会受到多种因素的影响，包括温度、二氧化碳浓度以及ATP和NADPH的可用性。例如，高温可能导致光呼吸率增加，这一过程与卡尔文循环竞争，从而降低光合作用的整体效率。总之，暗反应是光合作用的一个基本组成部分，使植物能够将无机碳源转化为有机化合物。通过理解暗反应背后的机制，我们能够深入了解植物如何为地球生态系统做出贡献，以及它们如何通过提供氧气和食物来支持生命。这一知识在应对全球挑战如气候变化和粮食安全时尤为重要，因为提高光合作用效率可能在可持续农业和环境保护中发挥重要作用。