BI226 Chapter 5: CHAPTER 5.docx
Document Summary
Contain only male or female reproductive organs: bisexual, monoecious and hermaphroditic. Contain both male and female reproductive organs: intersex. No matter what you do you get 50% hermaphodie, 50% male. Modes of sex determination: protenor mode (xx & xo, lygaeus mode (xx & xy) or (zz & zw, in both cases one sex produces two types of gametes (heterogametic sex, xy) while the other produces only one type of gamete (homogametic sex,xx). Y chromosome in humans: correlation of the presence of y chromosome in males and not in females. If there is a y chromosome in the karyotype, then male. Klinefelter syndrome 47,xxy: genitalia and internal ducts generally male, 1 in 1,000 male births, testes underdeveloped and fail to produce sperm, tall, long arms & legs, large hands & feet, masculine development occurs, but some feminine sexual development may occur. Slighty breast development & rounding of hips: slight decrease in intelligence (below normal range, result of nondisjunction event in parent.
