Anatomy Lecture 4 Embryology

Question 1

Define gastrulation

Answer 1

formation of the trilaminar disc

Question 2

Name the germ layers

Answer 2

Ectoderm
Mesoderm
Endoderm

Question 3

Name the 3 groups of mesoderm

Answer 3

Paraxial
Intermediate
Lateral plane

Question 4

Invagination of the ______ through the primitive streak forms the endoderm and mesoderm.

Answer 4

Invagination of the EPIBLAST CELLS through the primitive streak forms the endoderm and mesoderm.

Question 5

What germ layer do the genitals arise from?

Answer 5

Intermediate mesoderm

Question 6

What germ layer does the urinary system arise from?

Answer 6

Intermediate mesoderm

Question 7

What is the cloaca?

Answer 7

Cavity of urogenital ducts in early foetus

Question 8

At what week do the primordial germ cells within the yolk sac migrate to intermediate mesoderm?

Answer 8

Weeks 4-6

Question 9

Coelomic epithelium proliferates and thickens to form ______.

Answer 9

Coelomic epithelium proliferates and thickens to form GENITAL RIDGES.

Question 10

Proliferating epithelium will form somatic supports cells which envelop the primordial germ cells. This forms __________.

Answer 10

Proliferating epithelium will form somatic supports cells which envelop the primordial germ cells. This forms PRIMITIVE SEX CORDS.

Question 11

What is the other name of the Wollfian duct?

Answer 11

Mesonephric duct

Question 12

What is the other name of the Mullerian duct

Answer 12

Paramesonephric duct

Question 13

The mesonephric and paramesonephric duct connect to the posterior wall of the _______.

Answer 13

The mesonephric and paramesonephric duct connect to the posterior wall of the UROGENITAL SINUS.

Question 14

What phase of development happens when the indifferent gonad is present?

Answer 14

Bipotential phase

Question 15

Sexual differentiation occurs from week ____ onwards.

Answer 15

week 7

Question 16

In male development, the SRY region triggers the somatic support cells differentiate into ______.

Answer 16

Sertoli cells

Question 17

In male development, the primary sex cords form the ______.

Answer 17

Testis cords aka medullary cords

Question 18

Internal male genital is triggered by the ______.

Answer 18

Presence of the sex determining region on the Y chromosome

Question 19

The ______ connect the mesonephric tubules to the testis cords.

Answer 19

The RETE TESTIS connect the mesonephric tubules to the testis cords.

Question 20

Between the coelomic epithelium and testis cords, a thickened layer of connect tissue forms the ________.

Answer 20

Between the coelomic epithelium and testis cords, a thickened layer of connect tissue forms the TUNICA ALBUGINEA.

Question 21

Sertoli cells secrete _____ which leads to the degeneration of the _____ duct.

Answer 21

Sertoli cells secrete ANTI-MULLERIAN HORMONE which leads to the degeneration of the PARAMESONEPHRIC duct.

Question 22

Sertoli cells stimulate ______ to form ______ which secrete testosterone.

Answer 22

Sertoli cells stimulate GONADAL RIDGE CELLS to form LEYDIG CELLS which secrete testosterone.

Question 23

______ (hormone) induces the formation of the epididymis, seminal vesicles and vas D from the ______ duct.

Answer 23

TESTOSTERONE (hormone) induces the formation of the epididymis, seminal vesicles and vas D from the MESONEPHRIC duct.

Question 24

A mutation in anti-Mullerian hormone or is receptors would mean the Mullerian (paramesonephric) ducts would fail to regress. What is the name of this syndrome?

Answer 24

Persistent Mullerian Duct syndrome

Question 25

In persistent Mullerian duct syndrome, do the external genitalia resemble a male or female?

Answer 25

Male

Question 26

In persistent Mullerian duct syndrome, which internal genital organs are present?

Answer 26

Vagina, uterus, uterine tubes, testis

Question 27

What vertebral level to the testis originate at?

Answer 27

T10

Question 28

Gubernaculum aids the descents of the ____ in males.

Answer 28

Testis

Question 29

Put these covering of the testis in order from deep to superficial: - Scrotum - Internal spermatic fascia - Tunica vaginalis - External spermatic fascia - Cremaster muscle

Answer 29

- Tunica vaginalis - Internal spermatic fascia - Cremaster muscle - External spermatic fascia - Scrotum

Question 30

The prostate, bulbourethral glands and seminal vesicles are ______ of the male genital system

Answer 30

accessory glands

Question 31

What germ layer is the prostate derived from?

Answer 31

Endoderm

Question 32

What germ layer are the bulbourethral glands derived from?

Answer 32

Endoderm

Question 33

What germ layer are the seminal vesicles derived from?

Answer 33

Mesoderm

Question 34

What germ layer is the urethra derived from?

Answer 34

Endoderm

Question 35

In female development, germ cells differentiate into ______ and then into ______.

Answer 35

In female development, germ cells differentiate into OOGONIA and then into PRIMARY OOCYTES.

Question 36

In female development, somatic support cells differentiate into ______ and surround the primary oocytes. This forms the _____ in the ovary.

Answer 36

In female development, somatic support cells differentiate into GRANULOSA CELLS and surround the primary oocytes. This forms the PRIMORDIAL FOLLICLES in the ovary.

Question 37

What hormone is responsible for female external genitalia development?

Answer 37

Estrogen

Question 38

What hormone is responsible for the development of the paramesonephric ducts in the female?

Answer 38

Estrogen

Question 39

What structures of the female reproductive system do the paramesonephric (Mullerian) ducts give rise to?

Answer 39

Uterine tubes, uterus, superior vagina

Question 40

The fused caudal portion of paramesonephric ducts gives rise to the _____ and ______.

Answer 40

The fused caudal portion of paramesonephric ducts gives rise to the UTERUS and SUPERIOR VAGINA.

Question 41

In female development, what does the urogenital sinus give rise to?

Answer 41

Hymen and inferior vagina

Question 42

During weeks ____ the external genitalia are indistinguishable

Answer 42

4-7 | indifferent stage

Question 43

The prepuce (foreskin) of the glans penis is the only part of the penis formed from ______ germ cell layer.

Answer 43

Ectoderm | forms at week 12

Question 44

_____ occurs when the external urethral opening lies in an abnormal position along the ______ aspect of the penis.

Answer 44

HYPOSPADIAS occurs when the external urethral opening lies in an abnormal position along the VENTRAL aspect of the penis.

Question 45

The genital tubercle, urethral fold and genital swelling are parts of both male and female external genital development. T or F

Answer 45

True

Question 46

In female external genital development, the genital swelling goes on to form the ______.

Answer 46

Labium majora

Question 47

In female external genital development, the urethral fold goes on to form the ______.

Answer 47

Labium minora

Question 48

In female external genital development, the genital tubercle goes on to form the ______.

Answer 48

Clitoris