Inferences are steps in reasoning, moving from premises to conclusions. Charles Sanders Peirce divided inference into three kinds: deduction, induction, and abduction. Deduction is inference deriving logical conclusions from premises known or assumed to be true, with the laws of valid inference being studied in logic.
Meiosis is the process by which most eukaryotic organisms, those with cells having an organized nucleus, produces sex cells, the male and female gametes. Cells normally have two copies of each chromosome, one donated from each parent.
Nondisjunction can occur in mitosis or during meiosis I or II. If nondisjunction occurs in meiosis I, both chromosomes of a homologous pair. migrate to the same pole, leaving one daughter cell without a chromosome. The. cells go through meiosis II normally, producing four gametes with unusual num-. bers of chromosomes.