Answer:
The additional chromosome related to Down syndrome is chromosome 21, which is the product of an error in meiotic division.
Explanation:
Down syndrome is a genetic alteration that produces morphological and functional changes in individuals who have it, including the mongoloid facies. It is a condition called chromosome 21 trisomy.
Each gamete must contain the exact half of the chromosomes of a species, with each human chromosome having 23 chromosomes (n = 23). For this to occur, the sister chromatids must separate properly during meiosis division.
An error in meiosis, called non-disjunction, causes a gamete to contain an extra chromosome (n = 23 + 1), as the sister chromatids do not separate. This gamete, when joined to a normal gamete, produces a trisomy in the affected chromosome, being the trisomy of chromosome 21 the one that causes Down syndrome.
Learn more:
Trisomy 21 https://brainly.com/question/484286