Without nodes, there would be no blockchain. Nodes are essential to the function of a blockchain because they store, validate and propagate transactions across the network. Without nodes, there would be no decentralized ledger and no way to ensure the integrity of transactions.
Other related questions:
Q: What happens if all blockchain nodes go down?
A: If all blockchain nodes go down, the blockchain will be unavailable and no transactions can be processed.
Q: Do nodes store the entire blockchain?
A: No, each node stores only a portion of the blockchain.
Q: What if blockchain data is lost?
A: If the data on a blockchain is lost, it cannot be recovered.
Q: Can blockchain run out of space?
A: No, the blockchain will not run out of space.