Meiosis Vocabulary

Vocabulary flashcards related to Meiosis.

Gametes

Reproductive cells that unite to form a new individual during sexual reproduction.

Meiosis

Nuclear division that halves the chromosome number, essential for sexual reproduction.

Fertilization

The process where sperm and egg unite.

Sex chromosomes

Chromosomes that determine the sex of an individual.

Autosomes

Non-sex chromosomes.

Homologous chromosomes (Homologs)

Chromosomes of the same type, containing the same genes in the same position.

Homologous pair

A pair of homologous chromosomes.

Gene

A section of DNA that codes for a protein or RNA.

Alleles

Different versions of a specific gene.

Karyotype

Identifies the number and types of chromosomes present in a species.

Diploid

Having two homologs of each chromosome.

Haploid number (n)

The number of distinct types of chromosomes present in a cell.

Ploidy

Indicates the number of complete chromosome sets a cell contains.

Maternal chromosome

A chromosome that came from the mother.

Paternal chromosome

A chromosome that came from the father.

Polyploid

Organisms with three or more versions of each type of chromosome.

Unreplicated chromosome

A chromosome that consists of one double-helical molecule of DNA packaged with proteins

Replicated chromosome

A chromosome after DNA replication, consisting of two identical chromatids

Sister chromatids

The two identical chromatids in a replicated chromosome.

Non-sister chromatids

Chromatids on different members of a homologous chromosome pair.

Bivalent

Paired, replicated homologous chromosomes during prophase one and metaphase one of meiosis.

Haploid

Having one of each type of chromosome (n).

Diploid

Having two of each type of chromosome (2n).

Polyploid

Having more than two of each type of chromosome; may be triploid (3n), tetraploid (4n), etc.

Sister Chromatids

Two identical copies of a single chromosome that are connected by a centromere.

Meiosis I and II

Meiosis I separates the two homologs of each chromosome pair into two daughter cells; Meiosis II separates the sister chromatids of each chromosome into two daughter cells.

Reduction Division

Cell division that reduces the chromosome number from diploid to haploid.

Zygote

A diploid cell resulting from the fusion of two haploid gametes; a fertilized egg.

Synapsis

The pairing process of homologous chromosomes during early prophase I.

Chiasmata

Points where crossing over occurs between homologous non-sister chromatids.

Crossing Over

Exchange of genetic material between homologous non-sister chromatids.

Random Alignment

The random alignment of paired homologs at the metaphase plate.

Cytokinesis

The process of cell division.

Independent Assortment

The random distribution of maternal and paternal chromosomes to daughter cells during meiosis I.

Genetic Recombination

The generation of new combinations of alleles through independent assortment or crossing over.

Trisomy

Having an extra copy of a chromosome (2n+1).

Nondisjunction

Failure of sister chromatids or homologous chromosomes to separate during cell division.

n + 1 Gamete

A gamete with an extra chromosome (n+1).

n - 1 Gamete

A gamete with a missing chromosome (n-1).

Gametogenesis

The process of formation of gametes