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prefix-list vs access-list

You need to remember how an access list wildcard mask works. 192.168.1.0 0.0.0.255 Where you have a 0 bit in the wildcard then the corresponding bit within the IP Address must match. So in the example above 192.168.1 must match. Where you have a 1 bit then the Wildcard mask does not care about the corresponding bit within IP address (also known as the 'don't care bit), thus the 255 in the last octect means that the corresponding bit within the IP address can be anything between 1 and 255. Therefore when matching routes with an access list, the access list would let through 'Prefixes' from: 192.168.1.0 to 192.168.1.255 Obviously within this range there would be no routes that are advertised as routes from a routing protocol (like broadcast), however it does capture everything.
A Prefix list is far more precise 192.168.1.0/24 will only let through 192.168.1.0, if you wanted the prefix list to act like the access list, you would use the ge and le statements at the end of the prefix. My advice would be, when dealing with routes, and in particular BGP use a prefix list
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