It is thought that extracellular ligand binding to a receptor tyrosine kinase activates the intracellular catalytic domain by propagating a conformational change across the lipid bilayer through the single transmembrane a helix.

判断题Protein kinase A itself is different in different cell types, whichexplains why the effects of cyclic AMP vary depending on the target cell.

判断题How is it that different cells can respond in different ways to exactly the same signaling molecule even when they have identical receptors

判断题There is no fundamental distinction between signaling molecules that bind to cell-surface receptors and those that bind to intracellular receptors.

判断题Water has a high specific heat.

判断题The density of water is less than the density of ice.

判断题Both the GTP-bound a subunits and nucleotide-free b complexes, but not GDP-bound, fully assembled G proteins, activate other molecules downstream of G-protein-linked receptors.

填空题是细胞外基质的受体蛋白。在结构上，它们是异二聚体，。这种跨膜蛋白的细胞外部分有一个球形的头部，可与细胞外基质蛋白结合，而细胞质结构域则可与 相结合。

填空题编码载脂蛋白B的基因在肠组织中转录成mRNA后,第2153位的C被 形成U,使CAA密码转变成终止密码UAA, 使翻译提前终止。

填空题What is the major factor that determines the limit of resolution of a light microscope

填空题决定红细胞ABO血型的物质是糖脂，它由脂肪酸和寡糖素链组成。A型血糖脂上的寡糖链较O型多一个 ；B型血仅多一个 。