Molecular Basis of Inheritance

Practice flashcards covering key vocabulary and concepts from the lecture on the molecular basis of inheritance.

Deoxyribonucleotide

A monomer of DNA composed of a phosphate group, a sugar (deoxyribose), and a nitrogenous base (A, G, C, or T).

Phosphodiester bond

The covalent bond linking nucleotides together in a DNA polymer.

Double-stranded DNA

DNA molecules composed of two strands held together by hydrogen bonds between complementary bases (A with T, and G with C).

Anti-parallel arrangement

The orientation of the two strands in a double-stranded DNA molecule, where one strand runs in the 5' to 3' direction and the other runs in the 3' to 5' direction.

Semiconservative model

The mechanism of DNA replication where each new double-stranded DNA molecule consists of one old (parental) and one new (daughter) strand.

Leading strand

The DNA strand that is synthesized continuously during DNA replication.

Lagging strand

The DNA strand that is synthesized in short fragments (Okazaki fragments) during DNA replication.

Telomeres

The ends of linear chromosomes that shorten with each replication due to the inability of DNA polymerases to initiate synthesis at the 5' end.

Telomerase

An enzyme that extends telomeres in germline cells, preventing shortening during cell division.

Nucleosome

The fundamental unit of chromatin structure, consisting of DNA wrapped around a histone protein complex.

Chromatin packing

The process by which DNA is compacted with proteins to fit within a cell nucleus, affecting gene expression.

Okazaki fragments

Short DNA fragments synthesized on the lagging strand during DNA replication.

Base pairing

The specific hydrogen bonding between complementary nitrogenous bases (A with T, and G with C) in DNA.

Primase

An enzyme that synthesizes short RNA primers necessary for the initiation of DNA replication.

DNA ligase

An enzyme that joins Okazaki fragments on the lagging strand by forming covalent bonds between them.

Hydrogen Bonds

Weak bonds that hold together the complementary nitrogenous bases in a double-stranded DNA molecule.