Molecular Biology - DNA, RNA, and Gene Expression

These flashcards summarize key vocabulary and concepts in molecular biology related to DNA, RNA, and gene expression, preparing students for their exam.

Central Dogma

The framework that describes the flow of genetic information from DNA to RNA to protein.

Semi-conservative replication

A method of DNA replication where each new DNA molecule consists of one original strand and one new strand.

Transformation

The process by which genetic material from one bacterial strain is taken up by another strain.

DNA polymerase

An enzyme responsible for synthesizing new strands of DNA complementary to the template strand.

mRNA

Messenger RNA, a type of RNA that conveys genetic information from DNA to the ribosome for protein synthesis.

Transcription

The process where the information in a strand of DNA is copied into a complementary RNA strand.

Translation

The process where ribosomes synthesize proteins using the mRNA sequence as a template.

Codon

A sequence of three nucleotides in mRNA that specifies an amino acid.

Adenine (A)

A nitrogenous base in DNA and RNA, pairs with thymine in DNA and uracil in RNA.

Thymine (T)

A nitrogenous base in DNA that pairs with adenine.

Cytosine (C)

A nitrogenous base in DNA and RNA, pairs with guanine.

Guanine (G)

A nitrogenous base in DNA and RNA, pairs with cytosine.

RNA polymerase

The enzyme that synthesizes RNA from a DNA template.

Introns

Non-coding segments of RNA that are removed during RNA splicing.

Exons

Coding segments of RNA that remain after splicing and are expressed as part of the protein.

Spliceosome

A complex of enzymes and RNA that facilitates the removal of introns from pre-mRNA.

Anticodon

A sequence of three nucleotides in tRNA that pairs with the corresponding codon in mRNA.

Ribosome

Cellular machinery composed of rRNA and proteins that coordinates the translation of mRNA into a polypeptide.

Eukaryotes

Organisms whose cells contain a nucleus and other organelles enclosed within membranes.

Prokaryotes

Single-celled organisms lacking a nucleus, such as bacteria.

Gene expression

The process by which information from a gene is used to synthesize functional gene products, often proteins.

Polyadenylation

The addition of a poly(A) tail to a RNA molecule, which protects it from degradation.

Promoter

A DNA sequence where RNA polymerase binds to initiate transcription.