Meiosis and Heredity

Flashcards covering the key vocabulary and concepts related to meiosis and heredity.

Gene

A unit of heredity made up of segments of DNA that comprises chromosomes.

Locus

The specific location of a gene on a chromosome.

Gametes

Reproductive cells (sex cells) such as sperm and egg, which carry a complete set of chromosomes.

Somatic Cells

Non-sex cells that include all cells except gametes and the cells that give rise to gametes.

Haploid

A condition in which a cell has one complete set of chromosomes.

Diploid

A condition in which a cell has two complete sets of chromosomes.

Polyploid

A condition in which a cell has more than two complete sets of chromosomes.

Asexual Reproduction

A reproductive process that involves only one parent and typically results in offspring that are genetically identical to the parent.

Sexual Reproduction

A reproductive process that involves two parents and results in genetically variable offspring.

Meiosis

A process of cell division that reduces the chromosome number by half, resulting in four haploid daughter cells.

Synapsis

The pairing of homologous chromosomes during meiosis.

Crossing Over

The exchange of genetic material between non-sister chromatids during meiosis.

Chiasmata

The physical locations where crossing over occurs during meiosis.

Karyotype

An ordered display of chromosomes used to identify pairs and homologs.

Homologous chromosomes

Chromosomes that have the same genes at the same loci but may carry different alleles.

Independent Assortment

The random distribution of the pairs of genes on different chromosomes to the gametes.

Zygote

The single cell that results from the fusion of two gametes during fertilization.

Are somatic cells haploid or diploid? Are gamete cells haploid or diploid?

1. Somatic cells are diploid

2. Gamete cells are haploid

Meiosis 1

The first division in meiosis, where homologous chromosomes are separated into two daughter cells.

Meiosis 2

The second division in meiosis, where sister chromatids are separated into four haploid daughter cells.

Prophase 1

The first stage of meiosis 1, where homologous chromosomes pair up and undergo recombination, leading to genetic variation.

Metaphase 1

The second stage of meiosis 1, where homologous chromosomes line up at the cell's equatorial plane, ready for separation.

Anaphase 1

The third stage of meiosis 1, where homologous chromosomes are pulled apart to opposite poles of the cell, leading to the reduction of chromosome number.

Telophase 1

The final stage of meiosis 1, where the cell divides into two haploid daughter cells, and the nuclear membrane reforms around the chromosomes. (cytokinesis)

Prophase 2

The first stage of meiosis 2, where chromosomes condense and the nuclear envelope dissolves, preparing the cell for another division.

Metaphase 2

The second stage of meiosis 2, where chromosomes align at the cell's equatorial plate, ensuring proper division of sister chromatids during the upcoming anaphase.

Anaphase 2

The stage of meiosis 2 where sister chromatids are pulled apart to opposite poles of the cell, ensuring each daughter cell receives an equal set of chromosomes.

Telophase 2

The final stage of meiosis 2, where the chromosomes decondense, the nuclear envelope reforms, and cytokinesis occurs, resulting in four genetically distinct daughter cells.

Mutation

A change in the DNA sequence of an organism, which can lead to alterations in gene function and can be inherited by future generations.

Implications for genetic variation

Critical for evolution, population adaptation, and maintaining biodiversity in ecosystems