Nucleic Acids and Information Flow

These flashcards cover the key vocabulary and concepts regarding nucleic acids, DNA replication, and cell division.

Deoxyribonucleic acid (DNA)

The molecule that carries the genetic instructions for life and is composed of two long strands forming a double helix.

Nucleotide

The building blocks of nucleic acids, consisting of a phosphate group, a sugar (deoxyribose or ribose), and a nitrogenous base.

Purines

A class of nitrogenous bases in DNA, specifically adenine (A) and guanine (G).

Pyrimidines

A class of nitrogenous bases in DNA, which includes thymine (T) and cytosine (C).

Phosphodiester Bonds

Covalent bonds that link nucleotides together in a DNA or RNA strand, forming the backbone of the nucleic acid.

Hydrogen Bonding

The weak interactions between complementary base pairs in DNA that hold the two strands together.

Antiparallel Orientation

The arrangement of the two strands of DNA in opposite directions, with one strand running 5′ to 3′ and the other running 3′ to 5′.

Semiconservative Replication

The mechanism of DNA replication where each new DNA molecule consists of one old strand and one newly synthesized strand.

Okazaki Fragments

Short sequences of DNA synthesized on the lagging strand during DNA replication, which are later joined together.

Telomeres

The repetitive sequences at the ends of linear chromosomes that protect them from deterioration.

DNA polymerase

An enzyme that synthesizes new DNA strands during replication by adding nucleotides to a growing chain.

Cyclin-dependent kinases (CDKs)

Enzymes activated by cyclins that regulate the cell cycle progression by phosphorylating target proteins.

Cell Cycle Checkpoints

Regulatory points at which the cell cycle can be stopped to prevent the division of damaged or incomplete cells.

Cytokinesis

The final phase of cell division where the cytoplasm divides, creating two daughter cells.

Transcription

The process by which DNA is copied into RNA.

Translation

The process in which ribosomes synthesize proteins based on the information encoded in mRNA.