AP Biology Notes- DNA Replication and DNA stuffs

Double Helix

The structure of DNA, consisting of two complementary strands that run in opposite directions.

Nucleotide

The building block of DNA, made up of a sugar, phosphate group, and nitrogenous base.

Nitrogenous Bases

The four types of bases in DNA: Adenine (A), Thymine (T), Cytosine (C), and Guanine (G).

Base Pairing

The specific pairing of nitrogenous bases where Adenine pairs with Thymine and Guanine pairs with Cytosine.

Antiparallel

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

Purine

A class of nitrogenous base that includes Adenine and Guanine, characterized by a double-ring structure.

Pyrimidine

A class of nitrogenous base that includes Cytosine and Thymine, characterized by a single-ring structure.

Hydrogen Bonds

Weak bonds that hold nitrogenous base pairs together; Adenine and Thymine form two, while Guanine and Cytosine form three.

DNA Replication

The process in which a parent DNA strand serves as a template for the construction of new DNA strands.

Helicase

The enzyme that unwinds and unzips the DNA double helix to initiate replication.

Replication Bubble

An area where DNA unwinds and replication begins, created by Helicase.

DNA Polymerase

The enzyme responsible for synthesizing new DNA strands by adding nucleotides in the 5’ to 3’ direction.

Leading Strand

The continuously synthesized strand of DNA during replication.

Lagging Strand

The strand of DNA that is synthesized discontinuously in fragments during replication.

Okazaki Fragments

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

RNA Primer

A short sequence of RNA nucleotides added by primase to initiate DNA synthesis.

Exonuclease

The enzyme that removes RNA primers during DNA replication.

Ligase

The enzyme that connects the backbones of DNA between Okazaki fragments and newly synthesized sections of DNA.