The blood-testis barrier (abbreviated as BTB) is a physical barrier between the blood vessels and the seminiferous tubules of the animal testes. The barrier is formed by tight connections between the Sertoli cells, which are sustentacular cells (supp

The blastocyst is a structure formed in the early embryogenesis of mammals, after the formation of the morula, but before implantation. It possesses an inner cell mass (ICM), or embryoblast, which subsequently forms the embryo, and an outer layer of

A biorhythm is a hypothetical cycle in physiological, emotional, or intellectual well-being or prowess. Bio- pertains to life and rhythm pertains to the flow with regular movement. The theory has no more predictive power than chance, and has been lab

The Billings ovulation method (BOM) is a method which women use to monitor their fertility, by identifying when they are fertile and when they are infertile during each menstrual cycle. Users pay attention to the sensation at their vulva, and the app

Biastophilia (from Greek biastes, rape + -philia) and its Latin language-derived counterpart, raptophilia (from Latin rapere, to seize), also paraphilic rape, refer to a paraphilia in which sexual arousal is dependent on, or is responsive to, the act

Bi-curious is a term used to refer to someone who does not identify as bisexual or homosexual but feels or shows some curiosity in a relationship or sexual activity with someone of the same sex. The term can also apply to a person who generally ident

Harry Benjamin's Sex Orientation Scale (S.O.S.) was an attempt to classify and understand various forms and subtypes of transvestism and transsexualism in biological males. It was a seven-point scale (with three types of transvestism, three types of

Imprinting is the term used in psychology and ethology to describe any kind of phase-sensitive learning (learning occurring at a particular age or a particular life stage) that is rapid and apparently independent of the consequences of behavior. It w