A diagram representing the mechanism by which the NSCs will work can be found here: Process Flow Diagram
The relevant NSC will only provide a review of the science of the application. The output will be an opinion on the scientific merit and integrity of the proposal. The NSC will not provide an ethics review as required under the National Statement on Ethical Conduct in Human Research which will remain the remit of the Human Research Ethics Committee to which you apply.
The Terms of Reference for the Committees can be found here