Autoradiography
Technique that relies on the emission of radioactive particles from within the subject to produce an image.
Autosomes
Chromosomes that do not determine sex.
Centromere
Region of the chromosome that becomes attached to the spindle fibres during cell division.
Chromosome
A structure within the cell that bears the genetic material as a thread-like linear strand of DNA that carry the genes in a linear order (the human species has 23 pairs).
Diploid cells
Have nuclei containing two sets of chromosomes (2n), one set from each parent.
Down syndrome
A human genetic disease resulting from having an extra chromosome 21 (characterized by having a delay in mental development).
Gene
A hereditary unit consisting of a sequence of DNA that occupies a specific location on a chromosome and determines a particular characteristic in an organism.
Genome
The total genetic material of an organism.
Haploid cells
Have one chromosome of each pair (have one full set of the chromosomes that are found in its species).
Histones
Globular proteins associated to chromosomes in eukaryotic cells.
Homologous chromosomes
Chromosome pairs with genes for the same characteristics at corresponding loci.
Karyogram
Shows the chromosomes of an organism in homologous pairs of decreasing length.
Karyotype
A method of organizing the chromosomes of a cell in relation to number, size, and type.
Locus
The position of the gene on the chromosome (loci plural).
Naked DNA
The DNA in prokaryotic cells that is not associated with proteins.
Plasmid
The DNA of prokaryote in the circular chromosome.
Sequencing of DNA
To determine the order of nucleotide bases in a DNA molecule.
Sex chromosomes
The pair of chromosomes responsible for determining the sex of an individual.
Sister chromatids
Replicated forms of a chromosome joined together by the centromere and eventually separated during mitosis or meiosis.
Staining
Treating (specimens for the microscope) with a reagent or dye that makes certain structures visible without affecting others.
Allele
One of the possible alternatives of a gene, occupying a specific position on a chromosome, that controls the same trait.