CNS membranes

KC1. If you look at a cross section of spinal cord there are a pair of knobs at the back and a pair at the front; these are the posterior and anterior horn cells containing the synapses. The CNS is enclosed in a very thin membrane called the pia mater and a slightly thicker one called the arachnoid mater. A severe head injury for example produces a sub-arachnoid haemorrhage. The membranes have a good blood supply. DocDavid