Summary of Transcription and Translation: From DNA to Protein

Scientific Concepts and Processes:

DNA Structure: DNA consists of long molecules with millions of base pairs, with specific segments called genes that code for proteins.
Transcription:
- The process where enzymes use a DNA strand as a template to produce messenger RNA (mRNA).
- Involves RNA polymerase and Transcription factors binding to a promoter sequence.
- RNA polymerase synthesizes mRNA by reading the DNA template strand (antisense strand) from 3' to 5' and generating mRNA from 5' to 3'.
- RNA is synthesized with ribose and uracil instead of thymine.
- The process ends with the termination of RNA polymerase, resulting in the formation of mRNA.
RNA Processing: mRNA undergoes modifications before exiting the nucleus into the cytoplasm.
Translation:
- Occurs in ribosomes where mRNA is translated into proteins.
- Codons (sets of three bases on mRNA) correspond to specific amino acids carried by transfer RNA (tRNA).
- The reading frame determines how codons are read, with 64 possible codons coding for amino acids.
- The initiation of Translation begins with the start codon (AUG) and ends with stop codons.
- tRNA molecules bring amino acids to the ribosome, forming a growing polypeptide chain until a stop codon is reached.

Transcription:
- RNA polymerase binds to promoter.
- DNA strands separate; one strand serves as a template.
- mRNA is synthesized from the template strand.
- RNA polymerase terminates synthesis and releases mRNA.
Translation:
- mRNA binds to ribosome.
- Initiator tRNA attaches to the start codon.
- tRNAs bring amino acids based on codons.
- Polypeptide chain elongates until a stop codon is reached.