Translations:Zellmembran/2/en

The cell membrane (the cells of humans and animals) consists of two layers of different lipids in which proteins are stored or attached. The stored proteins serve the directed and controlled selective passage of substances (ion channels, transport proteins) and the transmembrane transmission of extracellular signals (signal transduction). Many membrane proteins are receptor proteins, which have specific binding sites (receptors) for chemical signalling substances (hormones, neurotransmitters), which control the passage of substances through the receptors or perform the signalling function. The proteins attached to the Z. extra- or intracellularly either represent enzymes or they form an intracellular supporting structure as structural proteins.