Medical Genetics: The Human Genome and Cell Division

Flashcards covering key vocabulary terms and definitions related to the human genome and cell division in medical genetics.

Genome

The sum total of the genetic information of our species, containing approximately 25,000 genes.

Karyotype

The characteristic chromosome complement in terms of the number and the morphology of chromosomes.

Locus

The precise position of each gene on a gene map.

Gene Map

A map detailing the genomic location of genes that is characteristic of each species.

Cytogenetics

The study of chromosomes, their structure, and their inheritance.

Germ-line Cells

Cells that give rise to eggs or sperm; all other cells are somatic cells.

Homologous Chromosomes

Chromosomes that carry matching genetic information, with the same genes in the same order.

Alleles

Alternate forms of the same gene.

Nucleotide

The basic building block of DNA, made up of a five-carbon sugar, a phosphate, and a nitrogenous base.

Polynucleotide Chains

Long chains formed by the polymerization of nucleotides.

Chromatin

The complex of DNA and proteins that make up chromosomes.

Nucleosome

The basic structural unit of chromatin, consisting of DNA wrapped around histones.

Mitochondrial DNA

A small circular DNA molecule found in mitochondria, inherited maternally and encoding 37 genes.

Single-copy DNA

DNA whose linear order of specific nucleotides is represented only once around the entire genome.

Repetitive DNA

DNA whose nucleotide sequence is repeated and contributes to chromosome structure and variation.

Meiosis

The process that results in the formation of reproductive cells with half the number of chromosomes.

Mitosis

Somatic cell division resulting in two identical daughter cells.

Chiasmata

The structures formed during meiosis where crossing over occurs.

Synapsis

The process of meiotic pairing that brings corresponding DNA sequences into alignment.

Independent Assortment

The process by which maternal and paternal chromosomes are shuffled during gamete formation.

Genetic Recombination

The process in meiosis that allows maternal and paternal alleles to be shuffled.

Bivalent Chromosome

A structure consisting of paired homologous chromosomes during prophase I of meiosis.

Centromere

The region of a chromosome where sister chromatids are joined.

Anaphase

A stage of mitosis and meiosis where chromosomes separate and move to opposite poles.

Telophase

The final stage of mitosis and meiosis where nuclear membranes reform around daughter nuclei.

Cytokinesis

The division of the cytoplasm in cell division, following mitosis.