K.C.S.E Biology Q & A - MODEL 2019PP1QN13
A female human being was found to have an extra sex chromosome in her cells.
(a) Give the total number of chromosomes in the female individual’s cells.
(b) Explain the possible cause of this condition.
(c) State two physical characteristics observed in the female individual with such a condition.
(b)Non-disjunction/failure of homologous chromosome to separate/segregate (in anaphase I) or failure of sister chromosome to separate/segregate (in anaphase II); resulting in an extra X sex chromosome, X chromosome in a cell having XXX instead of XX;
(c) infertile / ovary abnormalities;
Taller than average female;
(more pronounced) signs of obesity;
Abnormally curved fingers;
Widely spaced eyes;
Abnormally shaped breast bone;