Final answer:
Registrant members on the Board of the College represent professional interests and bring expertise, while public representatives ensure the public's needs are accounted for in decision-making.
Step-by-step explanation:
The main difference between registrant members and public representatives on the Board of the College is based on their roles and the groups they represent. Registrant members are usually professionals who are registered with the college and thus represent the interests of the profession itself, bringing specialized knowledge and expertise to the governance of the college.
Public representatives, on the other hand, are appointed to represent the interests of the general public with an outside perspective, ensuring that the public's needs and viewpoints are considered in the college's decisions and policies.