Chpt 4: Embryonic Development of Reproductive Structures

Question 1

coordinated series of events involving the merging of several types oftissue that will ultimately form complete reproductive glands and organs

Answer 1

embryogenesis

Question 2

embryonic germ layer that differentiates into the digestive system, lungs, and endocrine system

Answer 2

endoderm

Question 3

embryonic germ layer that differentiates into muscle, skeleton, cardiovascular, and reproductive system

Answer 3

mesoderm

Question 4

embryonic germ layer that differentiates into nervous system (hypothalamus, both pituitary lobes), skin (including mammary glands), and hair

Answer 4

ectoderm

Question 5

gives rise to embryo and germ layers that will develop into various specialized organs

Answer 5

inner cell mass (ICM)

Question 6

origin of the anterior lobe of pituitary from tissue in the roof of the embryo’s mouth, gives rise to a diverticulum fromthe roof of the mouth and grows dorsally

Answer 6

stomodial ectoderm

Question 7

diverticulum formed from the stomodeal ectoderm from roof of the mouth, grows dorsally, differentiates to form the adenohypophysis (anterior lobe)

Answer 7

Rathke’s pouch/pocket

Question 8

diverticulum developed from floor of brain and grows ventrally toward Rathke’s pouch, differentiates to form neurohypophysis (posterior lobe_

Answer 8

infundibulum

Question 9

contains axons and nerve terminals of neurons whose cell bodies are located in the hypothalamus

Answer 9

posterior (neurohypophysis) lobe

Question 10

cranial bone that begins to form around both lobes as development of pituitary nears completion

Answer 10

sphenoid bone

Question 11

protective cavity formed by sphenoid bone surrounding pituitary lobes

Answer 11

sella turcica

Question 12

nerves cause a direct and rapid release of axytocin that causes milk ejection

Answer 12

posterior lobe

Question 13

consists of specialized glandular epithelial cells that secrete glycoprotein hormones like FSH and LH that are not secreted by nerve cells

Answer 13

anterior lobe

Question 14

cells that originate from the base of the hind gut

Answer 14

primordial (primitive) germ cells

Question 15

means capable of differentiating alongtwodevelopmental pathways, the gonad of the new embryo is like this

Answer 15

bipotential

Question 16

location of the biopotential gonad, located on inner surface of the dorsal body wall,will eventually form the gonads, forms medial to embryonic kidneys

Answer 16

genital/gonadal ridge

Question 17

compact strands of tissued caused by the arrival of primitive germ cells in the genital ridge, and the subsequent stimulation of local CT to proliferate, cause the genital ridges to enlarge and push toward the developing kidneys (mesonephros)

Answer 17

primitive sex cords

Question 18

first distinct renal system, nonfunctional remnant of a primitive form of kidney found in lower animals

Answer 18

pronephros (pronephric kidney)

Question 19

replaces pronephros early in embryogenesis, functional, bilateral pair of intermediate kidneys, forms urine that is drined by bilateral pair of ducts (mesonephric/ Wolffian ducts)

Answer 19

mesonephros (mesonephric kidney)

Question 20

drains urine formed by mesonephros, extend caudally and empty into urogenital sinus

Answer 20

mesonephric ducts

Question 21

final renal form, begins to appear near the firs10-15% of gestation, fully functional by 30-35%, develops functional nephrons, serves as functional form of kidney in adult mammals

Answer 21

metanephros (metanephric kidney)

Question 22

new pair of ducts beside the mesonephric ducts, begins to develop at same time as mesonephros is developing, form on either side of mesonephric duct

Answer 22

paramesonephric/Mullerian ducts

Question 23

process regulated by a singl substance directed by gene on Y chromosome (SRY)

Answer 23

Sexual Differeniation

Question 24

XY chromosomes -> SRYprotein -> testes develop -> sertoli cells secrete anti-Mullerian hormone (AMH) and dihydrotestosterone ->(desert hedgehog (DHH) gene caused differentiation of fetal Leydig cells -> Testosterone -> development of male duct system AND AMH and testosterone degenerate paramesonephric duct -> dihydrotestosterone -> development of penis, scrotum, and accessory sex glands)

Answer 24

Formation of Male Reproductive System

Question 25

XX chromosomes -> NO SRY protein -> ovaries develop -> no AMH -> Paramesonephric ducts become oviducts, uterus, cervix, part of vagina -> Complete female tract

Answer 25

Formation of Female Reproductive System

Question 26

formed at level of the ribs,descend into scrotum late in gestation

Answer 26

testes

Question 27

rapid growth followed by rapid regression of a ligamentous structure moves the testis from the body cavity to the scrotum

Answer 27

gubernaculum

Question 28

layer of peritoneum immediately adjacent to testis

Answer 28

visceral vaginal tunic

Question 29

layer of peritoneum away from testis

Answer 29

parietal vaginal tunic

Question 30

space between the tunics, continuous with the body cavity that houses viscera

Answer 30

vaginal cavity

Question 31

failure oftestes to descend into scrotum

Answer 31

cryptorchidism

Question 32

occurs when a portion of the intestine passes through the inguinal canal into the vaginal cavity

Answer 32

inguinal herniation

Question 33

primordial follicles are formed along the outer surface of the ovary that will eventually become the cortex of the ovary

Question 34

provides ducts of female reproductive tract

Answer 34

paramesonephric ducts

Question 35

will become the broad ligament consisting of the mesometrium, mesosalpinx, and mesovarium

Answer 35

genital fold

Question 36

heifer born twin to a bull, heifer calf is sterile due to exposure to testosterone and AMH in utero but bull calf is fertile

Answer 36

freemartinism