VOCAB - Meiosis and DNA Replication and Heredity Characteristics

Crossing Over Definition

process that occurs during prophase 1 in which pieces of nonsister chromatids of homologous chromosomes are exchanged resulting in new genetic combination of chromosomes

Synapsis definition:

paring of homologous chromosomes in prophase 1 of meiosis

Chiasmata definition:

the site of crossing over of nonsister chromatids of homologous chromosomes

Homologous Chromosomes definition:

Chromosomes of the same shape size that contain genes for the same traits

Spermatogenesis definition:

Process of sperm production in males

Oogenesis definition:

Processes of egg production in females

Variability definition:

New genetic combinations/recombinant DNA

Nondisjunction definition:

The failure of homologous chromosomes to separate in meiosis 1 or sister chromatids in meiosis 2

Aneuploidy definition:

Condition in which one or more chromosomes or pieces of chromosomes are lacking or in excess

DNA Replication definition:

Process in which an identical copy of DNA is produced in a cell

Primer Definition:

starter strand of DNA or RNA that is required for replication

DNA Helicase definition:

enzyme responsible for unwinding and unzipping DNA during DNA replication

DNA Polymerase definition:

enzyme responsible for formation of DNA strand from a template

DNA Ligase definition:

Enzyme that unites Okazaki fragments of the lagging strand during DNA replication

Leading strand definition:

the daughter strand in DNA replication that is synthesized continuously

Lagging strand definition:

the daughter strand in DNA replication that is synthesized discontinuously

Chargaff’s Rules:

The number of purines in DNA always equals the number of pyrimidines, and that the amount of A equals T and G equals C.