My response would be what the apostle Paul said in Galations about in Christ that there is “no male or female”.
It doesn't necessarily have anything to do with roles or functions. Gender (male or female) makes a difference in marriage, because marriage needs one of each. Gender difference also makes a difference in the priesthod, because marriage is "a great mystery: but I speak concerning Christ and the church." (Ephesians 5:32). So the priest, who represents Christ, is symbolically male; the Church is symbolically female.
Not entirely explicable in human terms: hence the word "mystery."