Group items tagged

To understand the importance of elements to nutrition. Of the approximately 115 elements known, only the 19 highlighted in purple in Figure 1.26 are absolutely required in the human diet. These elements-called essential elements-are restricted to the first four rows of the periodic table (see Chapter 32 "Appendix H: Periodic Table of Elements"), with only two or three exceptions (molybdenum, iodine, and possibly tin in the fifth row). Some other elements are essential for specific organisms. For example, boron is required for the growth of certain plants, bromine is widely distributed in marine organisms, and tungsten is necessary for some microorganisms.

n. As such, this set of Essential Elements addresses a small number of science standards, representing a breadth, but not depth, of coverage across the entire standards framework. The purpose of the DLM Essential Elements is to build a bridge from the content in the general education science framework to academic expectations for students with the most significant cognitive disabilities. This version of the Essential Elements will provide content for science assessments for at least the next two years. The DLM Science Consortium intends to develop a learning map based on research about how students learn science content and engage in scientific and engineering practices in the next phase of the project. Revisions will be made when the science map is complete, at which time we anticipate the EEs will be aligned to the map with revisions and additions as appropriate.

Blood vessel growth-or angiogenesis-is critical for developing fetuses and to heal wounds. But it is also an essential element of how cancerous tumors grow and spread. Here, see a step-by-step explanation of how the process works and how anti-angiogenesis therapies might stop tumors before they become deadly.