Silicate tetrahedron. A siliconâoxygen tetrahedron is the Si O 4 anionic group, or a silicon atom with four surrounding oxygen atoms arranged to define the corners of a tetrahedron. This is a fundamental component of most silicates in the Earth's crust. siliconâoxygen tetrahedron is the Si O 4 anionic group, or a silicon atom with four surrounding oxygen atoms arranged to define the corners of a tetrahedron.
Best Answer: G proteins are special proteins that help plasma membrane receptors work. Many different signal molecules use G-protein linked receptors, including epinephrine and other hormones. It is part of a second messenger system. How it works is that some chemical messenger binds to the receptor at the membrane.
A G-protein-linked receptor activates G protein, which activates phospholipase C, which cleaves a membrane lipid to form IP3, which binds to a calcium channel on the ER, which opens to release calcium ions into the cytoplasm, which bind to an intracellular enzyme that carries out a response.