Cooing and babbling are early stages of speech development. As babies get older (often around 9 months), they begin to string sounds together, incorporate the different tones of speech, and say words like mama and dada (without really understanding what those words mean).
The map distance between two genes, measured in centimorgans or map units, equals the percentage recombination frequency between the two genes--the likelihood of offspring with copies of those genes on the same chromosome that come from different parents.ave. dna image by Allyson Ricketts from Fotolia.com. The concept of map distance in a genotype refers to where genes are located on a chromosome but does not refer to physical distance; rather, map distance refers to the tendency for a crossover to occur between genes.
Geneticists use maps to describe the location of a particular gene on a chromosome. One type of map uses the cytogenetic location to describe a geneâs position.The cytogenetic location is based on a distinctive pattern of bands created when chromosomes are stained with certain chemicals.Another type of map uses the molecular location, a precise description of a geneâs position on a chromosome.he chromosome on which the gene can be found. The first number or letter used to describe a geneâs location represents the chromosome. Chromosomes 1 through 22 (the autosomes) are designated by their chromosome number.