DNA, Proteins, and Mutations Review

Flashcards created to review key terminology and concepts related to DNA structure, replication, protein synthesis, and mutations for quiz preparation.

Nucleotide

The basic building block of DNA and RNA, consisting of a sugar, a phosphate group, and a nitrogenous base.

Nitrogenous Bases in DNA

The four nitrogenous bases found in DNA are adenine (A), thymine (T), cytosine (C), and guanine (G).

Base Pairing Rule

In DNA, adenine pairs with thymine and cytosine pairs with guanine.

Antiparallel Strands

Refers to the orientation of the two strands of DNA, where one runs 5’ to 3’ and the other runs 3’ to 5’.

DNA Replication

The process by which DNA makes a copy of itself before cell division.

Semiconservative Replication

The process of DNA replication where each new double helix is composed of one original strand and one new strand.

Leading Strand

The DNA strand that is synthesized continuously in the direction of the replication fork.

Lagging Strand

The DNA strand that is synthesized in short fragments (Okazaki fragments) away from the replication fork.

DNA Polymerase

An enzyme that synthesizes new DNA strands by adding nucleotides complementary to the template strand.

Helicase

An enzyme that unwinds and separates the two strands of the DNA double helix during replication.

Primase

An enzyme that synthesizes short RNA primers to initiate DNA replication.

DNA Ligase

An enzyme that joins Okazaki fragments together to create a continuous DNA strand.

Mutation

Any change in the DNA sequence that can affect genetic information.

Point Mutation

A mutation that affects a single nucleotide in the DNA sequence.

Frameshift Mutation

A mutation caused by insertion or deletion of nucleotides that alters the reading frame of the genetic code.

Codon

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

Gene Mutation

A change in the DNA sequence that affects the gene itself.

Chromosomal Mutation

A mutation that involves changes to the structure or number of chromosomes.

Sickle Cell Anemia

A genetic condition caused by a mutation in the hemoglobin gene, leading to abnormally shaped red blood cells.