Nondisjunction is the failure of homologous chromosomes or sister chromatids to separate properly during cell division. There are three forms of nondisjunction: failure of a pair of homologous chromosomes to separate in meiosis I, failure of sister chromatids to separate during meiosis II, and failure of sister chromatids to separate during mitosis.[1][2][3] Nondisjunction results in daughter cells with abnormal chromosome numbers (aneuploidy).
Calvin Bridges and Thomas Hunt Morgan are credited with discovering nondisjunction in Drosophila melanogaster sex chromosomes in the spring of 1910, while working in the Zoological Laboratory of Columbia University.[4]
Answer: regulate the thalamus
Explanation:
The hypothalamus does not regulate the function of the thalamus, rather it is found below the thalamus where it helps control appetite or feeding; body temperature; the amount of water in the blood (known as osmo-regulation); and sleep rhythms.
Thus, the hypothalamus does not regulate the thalamus.
Answer:
1) Crossing over
2) Independent assortment.
Explanation:
Gametes are formed resulting from the process of meiosis where the gametes get half of the original number of chromosomes. One phenomenon that happens during the prophase 1 of Meiosis and leads to the genetic diversification is crossing over. In this process , Here, homologous chromosomes pair up and exchange information present on genes from one another. When information is exchanged, it leads to the diversity of genetic data.
The second way of increasing genetic diversity is independent assortment that takes place during metaphase 1. In this process chromosomes from both father and mother cells align on equatorial plate of the cell in an independent manner. This means that some gamete can have 1 of many different chromosomal combinations.
This reshuffling of chromosomes during independent assortment enhances the genetic diversity of any organism and this also explains why kids of same parents can look or behave very different.
Hope it help!