Correct, but it also contains a nonce so the miners can change it to find the correct block 
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Why is it important that the blocks are cryptographically linked together? The linking of the blocks creates a digital stone dynamic where the transactions cannot be undone thus a secure network.
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What does the block structure look like in bitcoin?
the block structure consists of the previous blocks hash, the current blocks transaction hash, the nonce and the current block hash.
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It is important that the blocks are cryptographically linked together for the security and integrity of the Blockchain. The Blockchain structure in Bitcoin consists of blocks that are sequentially linked. Cryptography is imbedded within the data of the blocks and the links when they are hashed and the nonce is deciphered. The data of the previous block becomes part of the hash of the next block. The nonce and hash are proof of work and links each block in a sequential chain.
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That is what makes the blockchain immutable. you canāt change a block because it breaks the chain as all blocks are linked. changing one block will change the hash of the next block and so on.
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It is made up from the data meaning the transactions that are being involved in the block. the hash of the previous block. The nonce and the hash of the current block.
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So that tampering with a block alters the hash of each subsequent block. This forces the hacker to re-solve the crypto puzzle for each broken block. It would take so much time to solve the extra puzzles that itās not worth hacking blocks.
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Each block contains:
a) the hash of the previous block
b) the hash of all txās in the block
c) the nonce (random #)
All the above are included in the hash calculation of the block.
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Why is it important that the blocks are cryptographically linked together?
For the security, integrity and verifibiability of the block it is more difficult to change a block. When you change one block, you have to change all the blocks and create new hashed relations between the blocks, something which is almost impossible -
What does the block structure look like in bitcoin?
- block header
- block size
- transactions + transaction counter
- nonce
- prev block hash
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- Makes it immutable
2.The block has encrypted public address, a list of transactions. Each block has a reference to the last block to guard against tampering or inaccuracy.
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- Why is it important that the blocks are cryptographically linked together?
It is important that blocks are cryptographically linked together as this is how the miners secure the network, and the cryptographic hash function and data structures used are what gives the blockchain itās immutability, whereby you cannot change the data in any current block without nullifying the veracity of the data in the subsequent block (as is ensured by the use of hash pointers that use the hash of the previous block to add to the calculations of the current block). Any break in cryptographic links between blocks has such an immediate effect that it makes it practically impossible to scam the network due to the infeasible amount of time and cost to go back and change all previous blocks, and then go forward to catch up with other miners to win the next block reward, thus a huge waste of time and electricity/ money (and even if you succeeded in doing this for a number of blocks, a longer chain will always win the next block reward). The puzzle solving elements enabled by this cryptographically linked architecture also enable the network to moderate the difficulty (via the target number set for each block) and thereby also moderate the rate of block production and the intended inflation rate.
- What does the block structure look like in bitcoin?
Each block contains the following:
Version
Timestamp
Hash pointer
Transactions
Nonce
New hash derived
Between each block there:
A cryptographic chain / link back to the previous block whereby the hash pointer of the current block directly points back to the hash of the data of the previous block.
And to be honest it looks very complex until you understand it!!! More fun to draw then explain Iām pretty sure
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Why is it important that the blocks are cryptographically linked together?
A:To secure the blockchain and prevent tampering. The cryptographic puzzle preserves immutability in the network. -
What does the block structure look like in bitcoin?
Block number, Nonce, Transaction data, Previous hash, current hash. Miners also use metadata in a block header for each candidate block they are attempting to add to the blockchain.
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Blocks are not encrypted, they are hashed. Encryption is something different. Its okay to confuse these 2 terms in the beginning. Hash functions are one way functions, while encryption is a two way function.
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If any change happens in previous block, the link between blocks will be broken; so the cryptography has a fundamental role to ensure the integrity of blockchain.
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A block structure is formed by:
- Hash of previous block
- List of Transactions
- Nonce ( random number based on PoW algorithm)
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Answers:
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So that it remains one version of truth. The importance of it is to discourage altering or amending data from within a block.
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A block structure consist of data which includes inputs and outputs, previous hash, block hash and nounce.
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Cryptographic linkage ensures integrity of the blockchain. It makes network more trustworthy through maths.Cheating is disincentivised as remining is too costly
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In the block we have previous hash, transactions and nonce. The hash of current block base on all these three factors.
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Ah, thank you. I definitely got that confused.
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Hi again.
The two way communication is necessary I see. The difference escaped me. This has everything to do with the basic plan of the blockchain. Verification.
Thanks
Amazing homework! Keep up the great work.
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No problem. With the help of hash functions we can verify that the data in a block hasnāt been tampered with. 
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- Why is it important that the blocks are cryptographically linked together?
The blocks are cryptographically linked because the puzzle that miners have to solve as part of getting the block on the block chain is based on the previous links of the block chain along with the transaction on that block chain. Keeping in mind proof of work, any changes to a block chain will change the links, thus the puzzle. The miner will have to re-mine.
- What does the block structure look like in bitcoin?
The block structure in bitcoin are blocks with each having a designated space for the block number, Nonce, data, previous blockās hash, current blockās hash, and finally, a āMineā button. As long as the data, the Nonce, the previous hash, and current hash between blocks have been mined correctly, the blocks appear green in color. When you change the data in one block, you will break the link for the next block, subsequently changing the color of the blocks to red. When this happens to you will have to re-mine the first red block to obtain a corresponding hash to link to the next block. You need to repeat this procedure until all blocks are green again.
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It is important because in order to be approved by the network for your block to be appended or linked to the blockchain, each block has been given a unique hash by combining the hash of the previous block plus the hash of your blockās transactions plus a random number ānonceā. Because of their individual unique hashes, any internal change(s) to any block or the removal of any block will changes all of the hashes and break all of the links involved following the changed block. These unique mathematical hashes are an important security to guarantee the security and integrity of the network. This happens in a decentralized system which creates trust and mathematical certainty.
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Each individual block would have a network identification number and a unique hash for that block which would be the result of the combination of the previous blockās hash plus the hash of the transactions in the block plus the nonce. For example:
Block #1 Block #2 Block #3 etc
Network # linkage identifications ------->>
Nonce random numbers for each block ------>>
Data unique hash resulting from transactions in the block ---->
Previous Blockās Hash
This Blockās Unique Hash
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Thank you, really appreciate the feedback 
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