Obviously. The price of the altcoins are depending on bitcoin. If the price goes down then price of altcoin also gets down. There is a connection of them directly or indirectly
Yes in my opinion it happened because Bitcoin is the center of all Altcoins currently in circulation. Bitcoin can be mentioned is the Mother of all coins. so if the price of Bitcoin falls all prices of Altcoin will drop following it, that's because traders sell their Altcoin for their bitcoin.