DNA and RNA are like one-way streets. They have a specific direction, from the 5′ end to the 3′ end.

• 5′ end: Think of this as the beginning of a street where the phosphate group is unlinked.

• 3′ end: This is the ending of the street where the sugar is unlinked, ready to connect to another nucleotide like a continuing road.

Imagine constructing a road, you must begin from a particular point (5′) and continue towards the end (3′). Similarly, the nucleotides in DNA and RNA are connected in the same direction.

• Replication: Making Copies of DNA

It's like photocopying a document, but it always moves in the 5′ to 3′ direction.

• Real-World Example: Think of a train on a one-way track (from 5′ to 3′). The new rail (DNA strand) is constructed as the train moves along.

• Transcription: Turning DNA into RNA

Again, it's a 5′ to 3′ process.

• Real-World Example: It's like reading a book from left to right, making sure the words (nucleotides) are in the correct order.

• Translation: Making Proteins Using RNA

The ribosome, which reads RNA and constructs proteins, moves from the 5′ to 3′ end of the RNA.

• Real-World Example: Consider a factory assembly line where pieces (amino acids) are added in a specific order from start (5′) to finish (3′).