DNA, RNA, and Protein Synthesis

Vocabulary practice flashcards covering nucleic acid structures, the differences between DNA and RNA, and the mechanisms of transcription and translation.

DNA (Deoxyribonucleic Acid)

A double-stranded nucleic acid containing deoxyribose sugar and the nitrogenous base thymine that remains confined inside the nucleus and carries genetic information.

RNA (Ribonucleic Acid)

A typically single-stranded nucleic acid containing ribose sugar and the nitrogenous base uracil that is able to leave the nucleus.

Gene

A segment of DNA that contains the instructions to make one protein.

Nucleotide

The repeating structural subunit of nucleic acids, consisting of a sugar, a phosphate group, and a nitrogenous base.

Central Dogma of Molecular Biology

The biological principle stating that genetic information flows from DNA to RNA to protein ($\text{DNA} \rightarrow \text{RNA} \rightarrow \text{Protein}$), directing cellular survival and function.

Transcription

The first stage of protein synthesis occurring in the nucleus, in which a DNA sequence is copied into a complementary messenger RNA (mRNA) molecule.

Translation

The second stage of protein synthesis occurring in the cytoplasm at a ribosome, in which mRNA codons are read to join amino acids into a polypeptide chain.

RNA Polymerase

The enzyme responsible for copying a DNA base sequence into an RNA transcript inside the nucleus.

Messenger RNA (mRNA)

The type of RNA that carries a copy of a gene's genetic information from the nucleus out into the cytoplasm to the ribosome.

Transfer RNA (tRNA)

The type of RNA that transfers specific amino acids from the cytoplasm to the ribosome and matches its anticodon to the corresponding mRNA codon.

Ribosomal RNA (rRNA)

The type of RNA that forms a structural component of ribosomes and helps catalyze peptide bond formation.

Three Types of RNA

The three specialized RNA molecules in protein synthesis: mRNA (carries gene copy), tRNA (transfers amino acids), and rRNA (forms ribosomes).

Ribosome

The cellular structure in the cytoplasm that serves as the site of protein synthesis by reading mRNA and assembling polypeptide chains.

Codon

A sequence of three nitrogenous bases in an mRNA molecule that codes for a specific amino acid or stop signal.

Amino Acids

The basic building blocks of proteins that are linked together to build polypeptide chains.

Protein

A functional macromolecule formed from a folded polypeptide chain that performs many cellular functions and influences genetic traits.

Antiparallel DNA Strands

The structural arrangement in double-stranded DNA where two sugar-phosphate backbones run in opposite directions alongside one another.

Uracil

A pyrimidine nitrogenous base unique to RNA that replaces thymine and pairs with adenine.

Thymine

A pyrimidine nitrogenous base unique to DNA that pairs complementarily with adenine.

DNA Base-Pairing Rules

The rule specifying that adenine pairs with thymine ($\text{A}-\text{T}$) and cytosine pairs with guanine ($\text{C}\equiv\text{G}$) in DNA via hydrogen bonds.

Transcription Base-Pairing Rules

The rules governing RNA synthesis from DNA: DNA adenine pairs with RNA uracil ($\text{A} \rightarrow \text{U}$), DNA thymine pairs with RNA adenine ($\text{T} \rightarrow \text{A}$), and guanine and cytosine pair with each other ($\text{G} \leftrightarrow \text{C}$).