Untitled Flashcards Set

Nucleotide

Building blocks of DNA, consisting of a five-carbon sugar, phosphate, and a nitrogenous base.

Deoxyribose

The five-carbon sugar in DNA.

Double helix

The shape formed by two strands of DNA that wrap around each other.

Base pairing

The predictable matching of nitrogenous bases, where adenine pairs with thymine (A–T), and cytosine pairs with guanine (G–C).

Genome

The complete set of DNA for a species.

Chromosome

A distinct piece of DNA within a genome.

Euchromatin

Loose form of DNA in the nucleus that is active and available for transcription.

Heterochromatin

Condensed form of DNA in the nucleus that is generally inactive.

DNA replication

The process of copying DNA from one molecule to two identical molecules.

Helicase

The enzyme that unwinds the DNA double helix during replication.

DNA polymerase

The enzyme that adds nucleotides to a growing DNA strand during replication.

RNA primase

Enzyme that adds a short RNA primer to initiate DNA replication.

Okazaki fragments

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

Semiconservative replication

Method of DNA replication where each new molecule contains one original strand and one new strand.

Transcription

The process of making an RNA copy from DNA.

mRNA

Messenger RNA, a type of RNA that carries the genetic code from DNA to the ribosome.

Introns

Noncoding regions of mRNA that are removed during RNA processing.

Exons

Coding regions of mRNA that are expressed and translated into proteins.

Translation

The process of synthesizing proteins from mRNA.

Codon

A sequence of three nucleotides in mRNA that codes for a specific amino acid.

Ribosome

Cellular structure that assembles proteins by reading mRNA.

Operon

A functioning unit of DNA in prokaryotes that contains a cluster of genes regulated by a single promoter.

Mutation

An error in the genetic code that can result from DNA damage or incorrect repair.

Point mutation

A mutation that involves a change in a single nucleotide base.

Frameshift mutation

A mutation caused by insertions or deletions of nucleotides that alters the reading frame of codons.

Conjugation

The transfer of genetic material between bacterial cells via direct contact.

Recombinant DNA

DNA created by combining DNA from multiple sources.

Polymerase Chain Reaction (PCR)

A laboratory technique used to amplify DNA, creating billions of identical copies.

Gel electrophoresis

A technique that separates DNA fragments based on size and charge.

Restriction fragment length polymorphisms (RFLPs)

Variations in DNA fragments that are caused by differences in genetic sequences.