Flashcards in 1 - Repro - Origin of the Sexes Deck (30):
1
From which layer of the bilaminar disc does do the primordial germ cells develop from?
Epiblast
2
What determines whether the primordial gonads develop into ovaries or testes?
Whether they are colonised by a germ cell with XX or XY chromosomes
3
What part of the primordial gonad does a germ cell with XX chromosomes colonise?
Cortex
4
What part of the primordial gonad does a germ cell with XY chromosomes colonise?
Medulla
5
Name the gene expressed by Sertoli cells, which drives male development:
SRY gene
6
Which cell expresses the SRY gene which drives Male development?
Sertoli cells
7
What is the average length of the vas deferens?
~ 30-45 cm
8
Which part of the male genitalia develops from the urogenital sinus?
Prostate
Bulbourethral glands
Urethra
9
Which part of the male genitalia develops from the mesonephric duct?
Epidydimis
Vas deferens
Seminal vesicles
10
Which part of the female genitalia develops from the urogenital sinus?
Vagina
11
Which part of the female genitalia develops from the paramesonephric ducts?
Fallopian tubes
Uterus
Cervix
12
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
13
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
14
What is another name for the Wolffian ducts?
Mesonephric ducts
15
What is another name for the Mullerian ducts?
Paramesonephric ducts
16
Name the ducts from which the male genitalia develop from:
Mesonephric/Wolffian ducts
17
Name the ducts from which the female genitalia develop from:
Paramesonephric/Mullerian ducts
18
What ensures the regression of the Mullerian ducts for male development?
Mullerian Inhibitory Hormone (MIH) release from Sertoli cells
19
What substance is secreted by Sertoli cells causing the regression of the Mullerian ducts?
Mullerian Inhibitory Hormone (MIH)
20
What substance supports the development of the Mesonephric/Wolffian ducts?
Androgens
21
Name the parts of the external genitalia of an indifferent embryo:
- Genital tubercle
- Genital swelling
- Genital fold
- Urethral fold
22
What parts of the female external genitalia form from the urethral folds and genital swelling?
Labia minora
Labia majora
23
What part of the female external genitalia form from the genital tubercle?
Clitoris
24
Which hormone is vital for the closing of the urethral folds, for the development of the penis?
Dihydrotestosterone
25
Which part of the male external genitalia form from the genital swelling?
Testes
26
Which part of the male external genitalia form from the genital tubercle?
Glans penis
27
Name the remnant of the gubernaculum:
Males = Scrotal ligament
Females = Round ligament of the uterus + Ovarian ligament
28
Describe the location from where the testes and ovaries arise:
Upper lumbar area of posterior abdominal wall
29
In approx. which month of development do the testes reach the iliac fossa?
~ 3rd month
30