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]
These are the only options to pick from ?
One gets together with another and it happens then a child comes
Answer:
Birth is an example of a normally occurring positive-feedback mechanism.
Answer:
Geotropism is the influence of gravity on plant growth or movement. Simply put, this means that roots grow down and stems grow up. ... In this case, the stimulus is gravity. Upward growth of plant parts, against gravity, is called negative geotropism, and downward growth of roots is called positive geotropism.
Explanation: