Bitcoin is both a token AND a blockchain.

And the answer is yes, if the Bitcoin value goes down, it will most probably pull down with it most of altcoins as usual when there is a dip.

The rationale behind this is that when the BTC price goes down, people want to cash out to USD quickly so they sell their alts for bitcoin then bitcoin for USD. This is why usually alts dip even more then Bitcoin itself, they are all indexed on Bitcoin price.