Flashcards in 1 - Repro - Origin of the Sexes Deck (30)
From which layer of the bilaminar disc does do the primordial germ cells develop from?
What determines whether the primordial gonads develop into ovaries or testes?
Whether they are colonised by a germ cell with XX or XY chromosomes
What part of the primordial gonad does a germ cell with XX chromosomes colonise?
What part of the primordial gonad does a germ cell with XY chromosomes colonise?
Name the gene expressed by Sertoli cells, which drives male development:
Which cell expresses the SRY gene which drives Male development?
What is the average length of the vas deferens?
~ 30-45 cm
Which part of the male genitalia develops from the urogenital sinus?
Which part of the male genitalia develops from the mesonephric duct?
Which part of the female genitalia develops from the urogenital sinus?
Which part of the female genitalia develops from the paramesonephric ducts?
List some secondary female sex characteristics:
- Hair growth
- Breast development
- Subcutaneous fat redistribution (around hips, buttocks and thighs)
- Elbows hyperextend 5-8' more than males
List some male secondary sex characteristics:
- Hair growth
- Change in body composition: more muscle:fat
- Enlargement of larynx = voice deepens
- Larger hands, feet and nose
- Broadening of shoulders and chest
What is another name for the Wolffian ducts?
What is another name for the Mullerian ducts?
Name the ducts from which the male genitalia develop from:
Name the ducts from which the female genitalia develop from:
What ensures the regression of the Mullerian ducts for male development?
Mullerian Inhibitory Hormone (MIH) release from Sertoli cells
What substance is secreted by Sertoli cells causing the regression of the Mullerian ducts?
Mullerian Inhibitory Hormone (MIH)
What substance supports the development of the Mesonephric/Wolffian ducts?
Name the parts of the external genitalia of an indifferent embryo:
- Genital tubercle
- Genital swelling
- Genital fold
- Urethral fold
What parts of the female external genitalia form from the urethral folds and genital swelling?
What part of the female external genitalia form from the genital tubercle?
Which hormone is vital for the closing of the urethral folds, for the development of the penis?
Which part of the male external genitalia form from the genital swelling?
Which part of the male external genitalia form from the genital tubercle?
Name the remnant of the gubernaculum:
Males = Scrotal ligament
Females = Round ligament of the uterus + Ovarian ligament
Describe the location from where the testes and ovaries arise:
Upper lumbar area of posterior abdominal wall
In approx. which month of development do the testes reach the iliac fossa?
~ 3rd month