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Reproductive System Development (view source)
Revision as of 08:30, 22 August 2011
, 08:30, 22 August 2011→Sex Determination in Reptiles
==Sex Determination in Reptiles==
==Sex Determination in Reptiles==
Crocodilians, marine turtles, some terrestrial turtles and lizards undergo environmental sex determination. The important factor for sex determination in these species is the incubation temperature of the eggs as this determines the development of the gonads towards testes or ovaries. In crocodiles a higher temperature is male determining whilst in turtles a higher temperature is female determining.
Crocodilians, marine turtles, some terrestrial turtles and lizards undergo environmental sex determination. The important factor for sex determination in these species is the incubation temperature of the eggs as this determines the development of the gonads towards testes or ovaries. In crocodiles a higher temperature is male determining whilst in turtles a higher temperature is female determining.
==Sexual Differentiation of the Brain==
In the male testosterone is secreted into the blood and is able to cross the [[Blood_Brain_Barrier_-_Anatomy_%26_Physiology|blood brain barrier]]. Once across this barrier the testosterone is converted into '''estradiol''' and '''dihydrotestosterone'''. Although it is counter-intuitive, esradiol actually causes masculinisation of the male brain.
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In the female '''alpha-fetoprotein''' binds to estradiol resulting in this complex being unable to cross the [[Blood_Brain_Barrier_-_Anatomy_%26_Physiology|blood brain barrier]]. This mechanism protects the female brain from the masculinising effects of estradiol.
==EMBRYOLOGICAL DEVELOPMENT OF THE GENITAL TRACT==
==EMBRYOLOGICAL DEVELOPMENT OF THE GENITAL TRACT==