DNA Replication, Transcription, and Translation

These flashcards cover the key concepts and processes of DNA replication, transcription, and translation, including the roles of various enzymes and the steps involved in each process.

DNA Replication

The process by which a cell makes an exact copy of its DNA before cell division.

Helicase

The enzyme that unwinds the DNA double helix by breaking the hydrogen bonds between nitrogen bases.

Replication Fork

The Y-shaped region where DNA is opened during replication.

Template Strand

The original strand of DNA that guides the formation of new complementary strands.

Base Pairing Rule

The rule that dictates that Adenine (A) pairs with Thymine (T) and Cytosine (C) pairs with Guanine (G).

DNA Polymerase

The enzyme that adds nucleotides to form new DNA strands during replication.

Leading Strand

The DNA strand that is synthesized continuously toward the replication fork.

Lagging Strand

The DNA strand that is synthesized in short segments away from the replication fork, forming Okazaki fragments.

Okazaki Fragments

Short segments of DNA synthesized on the lagging strand during replication.

Ligase

The enzyme that connects gaps between Okazaki fragments to form a complete strand.

Transcription

The process of copying DNA into messenger RNA (mRNA).

RNA Polymerase

The enzyme that binds to DNA and synthesizes mRNA from the DNA template.

Promoter

A specific region of DNA that signals the start of transcription.

Pre-mRNA

The initial RNA strand synthesized from DNA before processing into mature mRNA.

mRNA Processing

The modifications (such as the addition of a 5' cap and 3' poly-A tail) that mRNA undergoes before being transported to the cytoplasm.

Translation

The process of assembling amino acids into a protein using mRNA.

Ribosome

The cellular structure where mRNA binds during translation to synthesize proteins.

Codon

A sequence of three nucleotides on mRNA that specifies a particular amino acid.

tRNA (transfer RNA)

Molecules that carry specific amino acids and have anticodons complementary to mRNA codons.

Polypeptide Chain

A chain of amino acids linked together during translation to form a protein.

Stop Codon

A codon in mRNA that signals the termination of protein synthesis.