Lecture #50 - Development of reproductive tracts (LAST ONE OMG) Flashcards
Development of the reproductive tract:
- What are the 4 components:
- _______ development = site of gamete production (oocyte/sperm production)
- oocytes and sperm develop from ____ ____ (primordial cells that form oocyte and sperm)
- development of the male and female _____ (either male or female but exceptions where both in one body)
- structures to _____ sperm to the oocye
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Slide 7 - what are examples of gonads, ducts and delivery system?
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Reproductive tract form from what germ cell layer?
Where do the germ cells migrate from? (they come about near one corner of the ____ ____)
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Indifferent gonads form from what?
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Gonad development:
(A germ cell is any biological cell that gives rise to the gametes of an organism that reproduces sexually)
- Germ cells (cells that oocyte and sperm develop from) are first seen where and WHEN does this start? (slide 13)
- They then migrate where? And how?
- Terms; what is mesonephros and what is genital ridge?
- What is the SRY gene and on what chromosome?
- In the absence of SRY gene, the gonad develops into what?
- In the presence of SRY gene, gonads differentiate into what?
- Germ cells migrate into the developing gonads in what week? Is this before or after the SRY gets turned on?
- Sex-determining region on the Y chromosome
- Mesonephros is a block of tissue associated with the genital ridge (it’s linked to the gonads) and this is where the two tubes are found
- Genital ridge is a ridge of tissue that frown out and becomes the gonad
Development of the ducts:
- In early development, before _____ _____, two tubes form from ______ _____ (…… tissue that’s linked to the gonads called the ______)
- What are the two tubes?
- In early development, before sex determination, two tubes form from intermediate mesoderm (mesonephros) (a tissue that’s linked to the gonads called the mesonephros)
- There is the wolffian duct (mesonephric duct) and the mullein duct (paramesonephric duct)
Indifferential stage:
- This is in both sexes and embryo forms this
- the paramesonephric duct (mullariain) is formed on the outside and on the inside is the mesonephric duct (wolffian)
- At this stage, they have two tubes (no sex differentiation yet)
Sex determination (overview):
- In male, the testes develop and the wolffian duct remains the mullerian duct degenerates because of the production of hormones signalling this
- In the female, the ovaries develop and there is no signalling so the wolffian duct degenerates and the mullarian duct remains
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Reproductive tract; female:
- If there is no SRY gene, what happens?
- What forms the uterus?
- So what four things does the malarian duct form? What if there is no mullarian duct?
- No SRY - no androgens are produced because no testis (no leydig) and thus the mesonephric/wolffian duct disappears (the wolfffian needs adrogens to remain)
- Lower parts of the 2 paramesonephric ducts join up to form the uterus
- The uterine tubes, the uterus + cervix, upper vagina.
Reproductive tract; male:
- SRY expression from the Y chromosome leads to _____ production (testosterone)….probably because testes develop
- In the presence of androgen, what persists?
- What else is produced in males? What cells secrete this? How does the presence of this affect the ducts?
- What happens at 12 weeks of development?
- What 3 things does the wolffian duct form?
- How do the testes get through the abdominal wall and into the scrotum>
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So with the tubes, how does each disappear (slide 28)
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Delivery structure:
Indifferential stage:
- how many holes?
- where is the genital swelling, genital folds and genital tubercule?
- waiting for what?
Waiting for androgens - if none then will because female genitals
What two hormones in male development?
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- What does the genital swelling make in the male and what does it get turned into in the female?
- What about the urogenital fold?
Go read slide 34 and back page
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Three instances where abnormalities can arise?
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