a) Protenor mode ff1111ff111 Figure 5.4 (a) The Protenor mode of Autosomes Xs Autosomes x sex determination XX Female(12A+2X) XO Male(12A+X) where t上 heterogametic sex is Gamete Gamete formation formation XO and produces HH+++1 gametes with or vithout the X H chromosome fi 145 Autosomes x Au autosomes Xs Male(12A+x) Female(12A+2X) 1: 1 sex ratioFigure 5.4 (a) The Protenor mode of sex determination where the heterogametic sex is XO and produces gametes with or without the X chromosome