BM component assembly and disassembly dynamics. BM components can be made, secreted, and incorporated into BMs from cells immediately adjacent to the BM or from distant cellular sources (yellow arrows). BM proteins also disassemble and then reassemble on BMs (pink arrow) or can be degraded (blue arrow). BM proteins are enlarged for clarity and are not to scale. Image by Siddharthan Balachandar Thendral.