Can I query Hyperledger Fabric ledger or update ledger without chaincode in peer?

I have simple question about Hyperledger Fabric. so here is my question:

I have simple question about Hyperledger Fabric. so here is my question:

I know that for committing peers (ordinary peers) it's not 100% necessary to have chaincode installed, but every peer should have ledger and that's 100% necessary.

so suppose I am committing peer and I have not chaincode installed, but I have ledger of course. Now new block arrives from ordering peer.

1) I should check blocks validity, so I need to query ledger

2) I should add this block, so I need to update ledger.

So how can I do this two above without chaincode? Isn't chaincode necessary for above operations? (query and update)

Can permissioned blockchain nodes be changed frequently being selected from a white list?

I need to implement a permissioned blockchain where nodes can be changed, based on a selection in a white list. Is there a way to implement this? I am reviewing hyperledger fabric, but I can't understand if I can change nodes after deployment.

I need to implement a permissioned blockchain where nodes can be changed, based on a selection in a white list. Is there a way to implement this? I am reviewing hyperledger fabric, but I can't understand if I can change nodes after deployment.

how tampering of data (already added block's data) in blockchain or worldstate is detected in blockchain and hyperledger fabric?

I have a couple of question regarding the tamper proof mechanism of the blockchain.

I have a couple of question regarding the tamper proof mechanism of the blockchain.

1) My understanding: I understood that hash of [ hash the previous block + content of current block ] will go as a hash to the next block. if we tamper content of a block the hash will change and the link to the next block will be broken.

My Question: If a suspect changed the content of a block long after the block got added, will the calculation of hash and placing the hash in the next block happens automatically ?. Suppose if some one has already illegally changed the content and the link is broken, is there an automatic mechanism to trigger the event that the link has been broken ?. At what time the tampered copy of blockchain will be identified and invalidated ?

2) My understanding: In Hyperledger fabric I uderstood that ledger = blockchain + worldstate. The world state is calculated based on the blockchain. The application will depend on worldstate values, the applications will not traverse through blockchain to find a value.

My questions are: i) how frequetly the worldstate is recalculated ?

ii) will a broken chain(in case of a tamper) is detected while re-calculating the worldstate

iii) what if a suspect tampers the worldstate on a peer. how this situation is set right ? will the tampering be detected during the consensus or any other acticity ?

I read and understood that the blockchain is tamper proof, but really want to understand which processes safe guard the BC ?