Some researchers have hypothesized that it is the cumulative binding of adenosine to a large number of sites that causes the onset of sleep.
一些研究人员假设，腺苷与大量位点的累积结合导致了睡眠的开始。
2
In mammalian cells, the promoter is a complex region containing bindingsites for many proteins that regulate gene expression.
在哺乳动物细胞里，启动子是一个包含着许多蛋白质结合位点的复杂区域，它调节基因的表达。
3
The protein has multiple subunits, each with a single ligand-binding site. Binding of ligand to one site decreases the binding affinity of other sites for the ligand.