Human Reproductive Biology
Richard E. Jones
Format: PDF / Kindle (mobi) / ePub
This acclaimed text has been fully revised and updated, now incorporating issues including aging of the reproductive system, and updates on the chapters on conception and Gamete Transport and Fertilization, and Pregnancy.
Human Reproductive Biology, 3rd edition emphasizes the biological and biomedical aspects of human reproduction, explains advances in reproductive science and discusses the choices and concerns of today. Generously illustrated in full color, the text provides current information about human reproductive anatomy and physiology.
The ideal book for courses on human reproductive biology - includes chapter introductions, sidebars on related topics of interest, chapter summaries and suggestions for further reading.
* All material competely updated with the latest research results, methods, and topics now organized to facilitate logical presentation of topics
* New chapters on Reproductive Senescence, Conception: Gamete Transport, Fertilization, Pregnancy: Maternal Aspects and Pregnancy: Fetal Development
* Full color illustrations, New companion website featuring latest information on current related topics
males and 12% of females, are bisexual in that they have had sexual experiences with the same and the opposite sex at one time or another in their adult life. Surveys more recent than Kinsey’s show that these frequencies of homosexual, heterosexual, and bisexual behaviors remain similar today. In the United States, 149 about 1.3% of adult females had homosexual sex in the past year and 3.8% since the age of 18. Among American males, 2.7% had gay sex in the previous year and 7.1% since age 18.
attack, and those sperm cells that do not move rapidly through these portions of the reproductive tract are vulnerable to destruction by the female immune system. The arrival of sperm in the uterus initiates a massive invasion of white blood cells (leukocytes) into the uterine lumen. These cells then begin to engulf the dead or dying sperm that have not yet moved up to the uterotubal junction. No more than a few thousand sperm reach this junction. The uterotubal junction is a muscular, tightly
120:100. This ratio is based on analysis of the sexes of early aborted embryos. This may indicate a greater fertilization rate by Y sperm than X sperm, perhaps because Y sperm are lighter and faster swimmers than X sperm. Alternatively, female embryos may die more frequently than male embryos at a very early stage in development, perhaps before implantation. The sex ratio of male births to female births (the secondary sex ratio) is 105:100. Thus, for reasons not yet understood, male fetuses
seminiferous tubules, and each tubule contains male germ cells in various stages of differentiation. The testes also contain some of the male sex accessory ducts that are discussed later in this chapter. Human Reproductive Biology, Fourth Edition. http://dx.doi.org/10.1016/B978-0-12-382184-3.00004-0 Seminiferous Tubules Each seminiferous tubule is lined on its inside by the seminiferous epithelium, which contains two kinds of cells: male germ cells and Sertoli cells. We will first look at how
causes secretion of adrenal steroid hormones (corticosteroids) such as cortisol. Cortisol in turn raises blood sugar levels, reduces inflammation, and combats the effects of stress. Still other basophils in the adenohypophysis secrete the polypeptide hormones lipotropin (LPH) and melanophore-stimulating hormone (MSH). Lipotropin breaks down fat to fatty acids and glycerol. MSH causes synthesis of a brown pigment, melanin, which is present in cells called melanophores. Finally, the basophils of