The codes for proteins, which are contained within DNA, are carried from the nucleus to ribosomes through a process called transcription and translation. Here's a breakdown:

1. Transcription:

* DNA to mRNA: Inside the nucleus, a specific segment of DNA (a gene) is copied into a messenger RNA (mRNA) molecule. This process is catalyzed by an enzyme called RNA polymerase.

* mRNA modification: The newly synthesized mRNA undergoes modifications like capping and polyadenylation, which protect it and help it bind to ribosomes.

2. Translation:

* mRNA export: The modified mRNA molecule is exported from the nucleus through nuclear pores.

* Ribosome binding: The mRNA molecule binds to a ribosome in the cytoplasm. Ribosomes are made up of ribosomal RNA (rRNA) and proteins.

* Translation: The mRNA sequence is read by the ribosome, and transfer RNA (tRNA) molecules bring the corresponding amino acids to the ribosome. Each tRNA molecule has an anticodon that matches a specific codon on the mRNA.

* Polypeptide chain formation: The amino acids are linked together in a specific order dictated by the mRNA sequence, forming a polypeptide chain.

* Folding and modification: The polypeptide chain then folds into a specific three-dimensional structure, often with the help of chaperone proteins. The protein may also undergo further modifications like phosphorylation or glycosylation.

Therefore, the code for a protein is not carried directly from the nucleus to the ribosome as DNA. Instead, it's first copied into an mRNA molecule (transcription) and then the mRNA travels to the ribosome where it's translated into a protein.