Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Y2 - Repro > Lecture 3 - Development Of The Reproductive Tracts > Flashcards

Lecture 3 - Development Of The Reproductive Tracts Flashcards

1
Q

What are the 3 stages of development before birth?

A

Pre-embryonic period
Embryonic period
Fetal period

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What is the time period for the pre-embryonic period?

What happens in this time period?

A

Conception to week 2

Fertilised ovum to blastocyst

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What is the time period for the embryonic period?

What happens in this time period?

A

2nd to 8th week

Germ layers and placenta develop and main body systems form

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What is the time period of the fetal period?

What are the main events that happen in the fetal period?

A

8 weeks onwards to birth

Further growth and development of organs

Locomotor system becomes functional

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What does the inner cell mass of the blastocyst form?

A

Embryo

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What does the outer cell mass of the blastocyst become?

A

Placenta

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What week does the bilaminar disc form?

A

Week 2

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What forms the bilaminar disc?

A

Embryoblast

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What 2 layers does the embryonic disc/bilaminar disc consist of?

A

Epiblast and Hypoblast

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What is gastrulation and what week does it occur?

A

When the bilaminar embryonic disc is converted into a trilaminar embryonic disc via the formation of a primitive streak

Week 3

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What are the 3 layers of the trilaminar disc?

A

Ectoderm
Mesoderm
Endoderm

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What is derived from ectoderm?

A

CNS
Epidermis of skin and glands
Pituitary gland

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What is derived from the mesoderm?

A

Uroogential tract (Repro tract)
MSK
Blood
Heart
Kidneys
Dermis of skin

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What is derived from endoderm?

A

Epithelium lining resp, GI, repro and urinary tract

Liver
Para thyroid and thyroid
Thymus
Pancreas

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What part of the mesoderm is the urogenital tract derived from?

A

Intermediate mesoderm

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Where do primordial germ cells originate from and where do they migrate to in the developing urogential tract?

A

Originates from yolk sac (epiblast layer) and migrates to the genital ridge

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

What determines the chromosomal sex of an embryo?

What is the default development?

A

Determined by what type of sperm fertilises the oocyte (sperm either X or Y)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

What occurs in the indifferent stage (initial step) of embryological development?

A

Primordial germ cells migrate along the retroperitoneum to the urogential ridge

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

What are primordial germ cells? (indifferent stage)

Where do they originate from?

A

Precursors of gametes that originate in the endoderm of the yolk sac and migrate to the genital ridge

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

What are the primitive sex cords?

What forms them?

A

The epithelium of the genital ridges proliferate and penetrates the intermediate mesoderm forming the primitive sex cords

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

In the indifferent stag, what forms the indifferent gonad?

A

Combo of germ cells and primitive sex cords can develop into either testes or ovaries

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

What chromosome determines whether thhe testes or ovary develops?

What gene is responsible for this?

A

Y chromosome

SRY gene

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

What affect does presence of the SRY gene have on development?

What if its absent?

A

Means testis determining factor is made so male development occurs

Means testis determine factor is absent so by default female development occurs

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

What week of development does the germ cells migrate to the urogential ridge?

A

4 weeks

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

What are the 2 types of primitive sex cord that can form?

Which one is for males?
Which one is for females?

A

Males = medullary cords

Females =primitive sex cord degenerates and doesn’t form the testis cord (forms cortical cords)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

If the SRY gene is present (male), what does this cause the medullary cords to go onto form?

A

Seminiferous tubules

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

What are the 2 types of cells that make up the seminferous tubules from the medullary cord in the testes?

A

Germ cells
Sertoli cells

28
Q

What is the function of the germ cells in the seminiferous tubules?

A

Become sperm cells later on (spermatogenesis)

29
Q

What is the function of the Sertoli cells in the seminferous tubules?

A

Supports spermatogenesis by providing nutrients to the germ cells

They are derived from the surface epithelium of the gland

30
Q

What are the cells between the medullary cords?

A

Leydig cells

31
Q

What is the function of leydig cells?

A

Produce testosterone

32
Q

What is the tunica albiginuea?

A

Thick fibrous layer around the testes

33
Q

What happens with the primitive sex cords to form the ovary?

A

The degenerate and do not form the testis cord

34
Q

What happens to the epithelium of the gonad in the ovary?

A

Contiues to proliferate making the cortical cords which go onto surround the germ cells forming the primordial follicle

35
Q

In men what cords form in gonad differentiation?

What do these cords form?

A

Medullary cords

Seminferous tubules (contain germ cells and Sertoli cell, around them tubes are leydig cells)

Testosterone then made

36
Q

In women what cords form in gonad differentiation?

What cells are involved in this?

A

Cortical cords

Granulosa cells
Thecal cells

37
Q

What are the 2 possible ducts that can develop in humans?

A

Mesonephric duct (Wolffian duct)

Paramesonephric duct (Mullerian duct)

38
Q

What ducts develop in men?

A

Mesonephric duct (Wolffian duct)

39
Q

What ducts develop in women?

A

Paramesonephric duct (Müllerian duct)

40
Q

What 2 things do the testis produce (when SRY gene present on Y chromosome) to support the development of the male internal genitalia (Mesonephric duct)?

A

Mullerian inhibiting hormone (MIH)

Androgens

41
Q

What is the function of Mullerian Inhibiting Hormone (MIH)?

A

Suppresses the development of the Paramesonephric / Müllerian duct

42
Q

What is the function of androgens?

A

Supports the development of the Wolffian duct

43
Q

If theres no functioning testes what ducts develop and why?

A

Female ducts (Paramesonephric ducts/Müllerian ducts)

No MIH made so Müllerian duct not suppressed
No androgens made so Mesonephric/Wolffian duct not supported so it regresses

44
Q

What does testosterone produced by the leydig cells stimulate the Wolffian duct to form?

A

Epididymis
Vas/ductus deferens
Seminal vesicles
Ejaculatory duct

45
Q

What does DHT/androgens stimulate the development of?

A

Forms the external genitalia

Prostate
Penis
Scrotum
Bulbourethral glands

46
Q

What does the Müllerian ducts in women give rise to?

A

Uterus
Vagina
Cervix
Oviducts

47
Q

What structures develop when theres no testosterone?

A

Clitoris
Labia majora
Labia minora

48
Q

What are the 3 general stages of Paramesonephric duct development?

A

Formation/elongation
Fusion
Resorption

49
Q

What happens in the elongation stage of Paramesonephric duct (mullerian) development?

A

Duct elongates toward the sinovagnial bowl

50
Q

What happens in the fusion stage of Paramesonephric duct (mullerian) development?

A

Ducts fuse together and with sinovaginal bowl

51
Q

What happens in the resorption stage of Paramesonephric duct (mullerian) development?

A

The duct walls that fused together resorb and part of the sinovaginal bowl resorb

52
Q

What are the 3 key components of the external genitalia in the indifferent stage?

A

Genital tubercle
Genital folds
Genital swellings

53
Q

Which is the structure in the middle in the indifferent stage, the genital fold or genital swelling?

A

Genital fold is in middle
Genital swelling is around the genital fold

54
Q

In the indifferent stage, where is the urogenital sinus?

A

In the centre of the genital fold

55
Q

What does the genital tubercle become:
In the man?
In the woman?

A

Man = glans penis
Woman = clitoris

56
Q

What does the genital fold become:
In the man?
In the woman?

A

Man = spongy urethra/shaft of penis

Woman = labium minora

57
Q

What does the genital swelling become:
In the man?
In the woman?

A

Man = scrotum
Woman = labium majora

58
Q

What leads to the development of the external genitalia?

A

Androgen hormones (DHT dihydrotestosterone)

59
Q

Why does no fusion occur in the development of the female genitalia?

A

No testis derived androgens (DHT)

60
Q

How do the gonads descend?

A

Testis descend from posterior abdominal wall down to the scrotum

Ovaries descends from the posterior abdominal wall to the pelvis

61
Q

What is the connective tissue that guides the testis and ovaries down to their location?

A

Gubernaculum

62
Q

In the female, what is the remnant of the gubernaculum called that’s left behind?

A

Round ligament

63
Q

What is Turner syndrome?

Genotype?
Phenotype?

What reproductive ducts develop?
What external genitalia develop?

A

Genotype = 45XO
So are phenotypically female (external genitalia) since no testosterone or androgens made

Ovaries end up degenerating (gonadal dysgenesis)

64
Q

What is Klinefelter syndrome?

Genotype?
Phenotype?

What duct develops and why?

A

47XXY
Phenotypically male (male external genitalia)
But lack of secondary characteristics like pubic and axillary hair and small testis (hypogonadism)

Mesonephric/Wolffian duct since MIH and androgens made

65
Q

What duct system develops in an individual with the karyotype 46XX with Congenital Adrenal Hyperplasia?

What would the external genitalia be?

A

Lots of androgens made so external genitalia looks more male since more fusion happens

Paramesonephric duct (Müllerian duct) develops since theres no Y chromosome so no MIH produced

66
Q

What ducts develop with a girl that has the genotype 46XY with complete androgen insensitivity syndrome?

A

Testis develop since Y chromosome present
MIH made so Paramesonephric duct not made
But they are insensitive to androgens so the mesonephric ducts dont develop either so no ducts develop

67
Q

What tissue do the gonads develop from?

A

Intermediate mesoderm in abdomen

Y2 - Repro (19 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2025 Bold Learning Solutions. Terms and Conditions