What is the purpose of protective membranes in mammals?

Protective membranes in mammals, such as the meninges surrounding the brain and spinal cord, serve to shield the central nervous system from physical injury and infection. They also help maintain the chemical environment necessary for proper neuronal function. Additionally, these membranes provide a barrier against pathogens while allowing for the exchange of essential nutrients and waste products. Overall, they play a critical role in protecting vital neurological structures while supporting their physiological needs.