Amoeba Sisters Lecture: How DNA Results in a Trait

Introduction

DNA contains genetic information that codes for traits like eye color.
Eye color is determined by a pigment made with proteins coded by genes.
Protein Synthesis: The process through which DNA leads to protein creation.
Importance of proteins: Involved in transport, structure, function as enzymes, and protection.

RNA, like DNA, is a nucleic acid but has differences crucial for protein synthesis.
Transcription and Translation: Two major steps in protein synthesis.

Occurs in the nucleus.
Process:
- RNA polymerase uses DNA to create complementary RNA bases.
- Formation of single-stranded mRNA (messenger RNA).
- mRNA is initially edited before it's functional.
mRNA leaves the nucleus, entering cytoplasm to attach to ribosomes (made of rRNA - ribosomal RNA).

Takes place at ribosomes in the cytoplasm.
tRNA (transfer RNA): Carries amino acids, the building blocks of protein.
Codons and Anticodons:
- mRNA codons (triplets) direct tRNA to bring specific amino acids.
- tRNA uses anticodons to match with mRNA codons and transfer amino acids.
- Example: Codon AUG, anticodon UAC.
- Methionine is linked to the start codon AUG.
Codon Chart: Helps determine which amino acids are coded by which mRNA codons.
Multiple codons can code for the same amino acid.
Peptide Bonds: Connect amino acids to form proteins.

Translation ends with a stop codon, indicating the completion of protein synthesis.
Result: Chain of amino acids sequenced according to mRNA coding (and ultimately the DNA).
DNA directs protein building with the help of mRNA, rRNA, and tRNA.

Protein folding/modification and transport vary according to protein structure and function.
Future topics: Protein folding, modifications, and transport.

Stay curious and explore more complex details on your own!