在海牙中,石共定向的机制
Christopher E Killian1, Rebecca A Metzler, Y U T Gong
1Department of Physics, University of Wisconsin, Madison, Wisconsin 53706, USA.
Journal of the American Chemical Society
|December 4, 2009
概括
海的牙使用无形碳酸 (ACC) 前体. 固态二次核化指导这些复杂的生物矿物质中的晶体同向.
科学领域:
- 生物矿物化 生物矿物化
- 材料科学 材料科学 材料科学
- 古生物学的古生物学
背景情况:
- 海的牙是复杂的石生物矿物.
- 皮动物表现出共同定向的石结晶学轴.
- 在皮动物中,酸盐共同定向的机制尚不清楚.
研究的目的:
- 研究紫色海牙中的石晶体方向.
- 阐明生物矿物形成中的晶体共同定向的机制.
- 探索无形碳酸 (ACC) 在生物矿物化中的作用.
主要方法:
- 高分辨率的X射线光电子发射光谱显微镜 (X-PEEM).
- 微光束X射线衍射 (muXRD). 微光束X射线衍射.
- 分析 *Strongylocentrotus purpuratus* 牙中的石结构.
主要成果:
- 在牙板,纤维和多晶矩阵中确定了明显的石c轴方向.
- 无形碳酸 (ACC) 被观察到作为牙形成端的前体.
- 固态二次核化被证明是聚晶矩阵中共定向纳米粒子的机制.
结论:
- 固态二次核化是海牙中实现同定向酸盐的关键机制.
- 无形碳酸前体在这个过程中起着至关重要的作用.
- 这种机制可能是不同类型生物矿物质形成的一般原则.
相关概念视频
01:21Tooth Anatomy
The human tooth enables us to eat a variety of foods, speak clearly, and even aid in shaping our faces. Teeth are composed of various elements that work together. Here's a detailed look at the anatomy of a human tooth.
The Crown, Neck, and Root
The visible part of the tooth is referred to as the crown. It's covered by enamel, the hardest substance in the human body. The crown is uniquely shaped for each type of tooth, allowing for different functions such as cutting, tearing, or grinding food.
The Crown, Neck, and Root
The visible part of the tooth is referred to as the crown. It's covered by enamel, the hardest substance in the human body. The crown is uniquely shaped for each type of tooth, allowing for different functions such as cutting, tearing, or grinding food.
01:18The Bone Matrix
Bone contains a relatively small number of cells entrenched in a matrix of collagen fibers that provide an adherent surface for inorganic salt crystals. Both components of the matrix, organic and inorganic, contribute to the unusual properties of bone. Without collagen, bones would be brittle and shatter easily. Without mineral crystals, bones would flex and provide little support. This can be observed by an experiment: when the minerals of a bone are dissolved by soaking the bone in acid or...
01:21Skeleton and Calcium Homeostasis
Calcium is not only the most abundant mineral in bone but also the most abundant mineral in the human body. Calcium ions are needed for bone mineralization, tooth health, heart rate regulation and strength of contraction, blood coagulation, the contraction of smooth and skeletal muscle cells, and the regulation of nerve impulse conduction. The average calcium level in the blood is about 10 mg/dL. When the body cannot maintain this level, a person will experience hypo or hypercalcemia.
02:42Ionic Crystal Structures
Ionic crystals consist of two or more different kinds of ions that usually have different sizes. The packing of these ions into a crystal structure is more complex than the packing of metal atoms that are the same size.
Most monatomic ions behave as charged spheres, and their attraction for ions of opposite charge is the same in every direction. Consequently, stable structures for ionic compounds result (1) when ions of one charge are surrounded by as many ions as possible of the opposite...
Most monatomic ions behave as charged spheres, and their attraction for ions of opposite charge is the same in every direction. Consequently, stable structures for ionic compounds result (1) when ions of one charge are surrounded by as many ions as possible of the opposite...
00:51Synthesis and Functions of Calcitonin
Calcitonin, a vital polypeptide hormone, regulates calcium levels within body fluids. It is released by the parafollicular cells, also known as C cells, situated in the follicular epithelium of the thyroid gland. Calcitonin responds to fluctuations in blood calcium levels and the influence of gastrointestinal hormones like gastrin and cholecystokinin.
The exact mechanisms by which calcitonin operates in calcium homeostasis remain elusive, but its significance is evident in several vital...
The exact mechanisms by which calcitonin operates in calcium homeostasis remain elusive, but its significance is evident in several vital...
01:17Hormones and Bone Tissue
The endocrine system produces and secretes hormones, which interact with the skeletal system. These hormones control bone growth, maintain bone once it is formed, and remodel it.
Hormones That Influence Osteoblasts and/or Maintain the Matrix
Several hormones are necessary for controlling bone growth and maintaining the bone matrix. The pituitary gland secretes growth hormone (GH), which, as its name implies, controls bone growth. This happens in several ways: first, it triggers chondrocyte...
Hormones That Influence Osteoblasts and/or Maintain the Matrix
Several hormones are necessary for controlling bone growth and maintaining the bone matrix. The pituitary gland secretes growth hormone (GH), which, as its name implies, controls bone growth. This happens in several ways: first, it triggers chondrocyte...