Different Form Fields for Different Requirements.

HI Guys,

I am working on a Job Application Project, Admin Panel and Front End..Add Vacancy from Admin panel and Apply from Front End Against a job using Application form. Requirements are.

1. When Applying for a Specific job, Input Fields in the Application form can change for different Jobs. like some job can ask for Gender and some can ask for Age..?

Please Guide when Adding Vacancies, how can i Acheive point 1.. so different jobs have different Requirements...