Meiosis and Genetic Variation

Flashcards focusing on key vocabulary related to meiosis, genetic diversity, and chromosomal abnormalities.

Meiosis

• A type of nuclear division in eukaryotes
• Produces four haploid genetically unique daughter nuclei (gametes)

Haploid

• A cell with half the number of normal chromosomes
• Typically represented by 'n'

Diploid

• A cell that contains two complete sets of chromosomes
• One from each parent
• Represented by '2n'

Zygote

• The new cell formed by the fusion of male and female gametes
• Occurs during fertilization

Interphase

• Stage of the cell cycle
• Where DNA replication occurs before meiosis

Crossing over

• Exchange of equivalent sections of DNA
• Occurs between non-sister chromatids during Prophase I of meiosis

Independent assortment

• Maternal and paternal chromosomes oriented randomly
• Occurs during metaphase I and II

Non-disjunction

• Error in meiosis
• Chromosomes or chromatids fail to separate properly
• Leads to gametes with an abnormal number of chromosomes

Trisomy

• Condition with an extra chromosome
• Three copies of a chromosome instead of the usual pair

Monosomy

• Condition with one less chromosome
• Only one chromosome instead of two

Karyotype

• Number and types of chromosomes in a eukaryotic cell
• Often displayed in a karyogram

Turner Syndrome

• Chromosomal disorder from monosomy X
• Female inherits only one X chromosome
• Leads to various developmental