Does organization WSDL has same structure for previous versions of CRM like 2016/2015/2013/2011?

Hi,

I am working on MS Dynamics CRM 2016 integration project where I am analyzing organization and discovery service.

I have below queries:

1. Does Organization WSDL has same structure across all CRM versions like 2016/2015/2013/2011?
2. Can I use latest 2016 Organization WSDL for previous product for performing CRUD operation?
3. Does previous versions of CRM has same operation as supported by CRM 2016 (create/update/delete/retrieve/retrievemultiple/execute/associate/disassociate)?

Thanks