Genetics and Protein Synthesis

These flashcards cover key concepts from gene structure and function, RNA types, protein synthesis processes, and mutations.

What does the one-gene-one-enzyme principle state?

Each step in a biochemical pathway is controlled by a specific gene, leading to the production of a specific enzyme.

What is the flow of information in a cell regarding gene expression?

DNA → RNA → protein.

What are the three major types of RNA?

Messenger RNA (mRNA), Transfer RNA (tRNA), Ribosomal RNA (rRNA).

What role does mRNA play in protein synthesis?

mRNA copies and carries information from DNA to the ribosome in the cytoplasm.

How is the sequence of amino acids determined?

The sequence of amino acids is determined by the codons on the mRNA.

What happens during transcription?

DNA is transcribed into mRNA in the nucleus.

What initiates the process of translation?

The start codon AUG on the mRNA, which codes for the amino acid methionine.

What are introns and exons?

Introns are non-coding sequences of DNA, while exons are coding sequences that appear in the final mRNA.

What is a mutation?

A change in the base sequence of DNA that can be passed to the next generation.

What type of mutation is characterized by the replacement of one base for another?

Substitution mutation.

What effect can deletions or insertions have on DNA sequences?

They can cause a frameshift, which drastically alters the resulting protein.

Define carcinogens.

Mutagens that can cause cancer.

How do mutations provide genetic variability?

By altering genes, mutations contribute to the diversity necessary for evolution.

What is the primary control mechanism for gene expression in prokaryotes?

The operon model, which includes simultaneous transcription and translation.

What is one consequence of gene mutations?

They can lead to genetic diseases such as Sickle Cell Anemia and Cystic Fibrosis.