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Biological patterns such as animal markings, the segmentation of animals, and phyllotaxis are formed in different ways.
Biological patterns such as animal markings, the segmentation of animals, and phyllotaxis are formed in different ways.
动物标记、动物分节和叶序等生物学模式是以不同的方式形成的。
In developmental biology, pattern formation describes the mechanism by which initially equivalent cells in a developing tissue in an embryo assume complex forms and functions. Embryogenesis, such as of the fruit fly Drosophila, involves coordinated control of cell fates. Pattern formation is genetically controlled, and often involves each cell in a field sensing and responding to its position along a morphogen gradient, followed by short distance cell-to-cell communication through cell signaling pathways to refine the initial pattern. In this context, a field of cells is the group of cells whose fates are affected by responding to the same set positional information cues. This conceptual model was first described as the French flag model in the 1960s. More generally, the morphology of organisms is patterned by the mechanisms of evolutionary developmental biology, such as changing the timing and positioning of specific developmental events in the embryo.
In developmental biology, pattern formation describes the mechanism by which initially equivalent cells in a developing tissue in an embryo assume complex forms and functions. Embryogenesis, such as of the fruit fly Drosophila, involves coordinated control of cell fates. Pattern formation is genetically controlled, and often involves each cell in a field sensing and responding to its position along a morphogen gradient, followed by short distance cell-to-cell communication through cell signaling pathways to refine the initial pattern. In this context, a field of cells is the group of cells whose fates are affected by responding to the same set positional information cues. This conceptual model was first described as the French flag model in the 1960s. More generally, the morphology of organisms is patterned by the mechanisms of evolutionary developmental biology, such as changing the timing and positioning of specific developmental events in the embryo.
在发育生物学中，斑图生成描述了胚胎组织发育中最初的等效细胞呈现出复杂形态和功能的机制。'''以果蝇为例，<font color="#ff8000"> 胚胎发育Embryogenesis</font>'''涉及到细胞命运的协调控制。这一模式的形成是遗传控制的，通常涉及一个场中的每个细胞沿着形态原梯度感知和响应其位置，然后通过细胞信号通路进行短距离的细胞间通信以完善初始模式。在此背景下，'''<font color="#32CD32">细胞场 a field of cells</font>'''是指通过响应同一组位置信息线索而影响其命运的一组细胞。这个概念模型最早在20世纪60年代被描述为法旗模型。一般地，生物体的形态是由进化发育生物学的机制所决定的，如改变胚胎中特定发育事件的时间和位置。
虎灌木和冷杉波等植被模式形成的原因不同。在尼日尔等干旱国家，植物生长受到降雨的限制，虎灌木由干旱斜坡上的带状灌木组成。每一条大致水平的植被带都可以从紧靠其上方的裸露地带吸收雨水。
虎灌木和冷杉波等植被模式形成的原因不同。在尼日尔等干旱国家，植物生长受到降雨的限制，虎灌木由干旱斜坡上的带状灌木组成。每一条大致水平的植被带都可以从紧靠其上方的裸露地带吸收雨水。
===Chemistry===
===Chemistry===