Question

DULUI U Ulange and black fur. 13. What is a Barr body? How is it related to the Lyon hypothesis? *17. For each of the following chromosome complements, what is the phenotypic sex of a person who has a. XY with the SRY gene deleted? b. XX with a copy of the SRY gene on an autosomal chromosome? c. XO with a copy of the SRY gene on an autosomal chromosome? d. XXY with the SRY gene deleted? e. XXYY with one copy of the SRY gene deleted? 18. A normal female Drosophila produces abnormal eggs that contain all (a complete diploid set) of her chromosomes. She mates with a normal male Drosophila that produces normal sperm. What will th sex of the progeny from this cross be? 10 T utain malaman dan ha nafananatic famala car

Answer 1

19) Bare body - Barve body cuso known as sex chromatin body. This is one of the two inactive – X-chromosome in mammalian female cells. gt remains condensed dwing Go bhase and completely silent in transcription. Where as other X-Chromosome in the cell is de condensed transcriptionally active. The inactivation of x- chromosome known as Lyonization. Lyonization is an epigenetic process that Öffect the expression of gene without any change in DNA sequence.

7 Lyon Hypothesis The two x-chromosome in female cell derive from the male gamete (paternal XP) and female gamete (Maternal xml) . Both XP and XM choromo some are functional in very early female mammalian emboyo and when cy to differentiation starts in embryonic tissue of the emboyo X-chromosome inactivation occus. The candom inactivation of xm and xp in Somatic cell during the emboyonic development called as Lyon Hypothesis.