ppwt 6 conception and pregnancy

Question 1

does fertilization means pregnancy

Answer 1

no

Question 2

what happens during the binding of a sperm and the oovocyte

Answer 2

1. bring the ZP in the head of the perm it as a post translation modification. They bind to the ZP and release acrosomal enzymes that degrade the zona pelucida and they can enter the egg
2. upon binding further, there are other kind of receptors that can bind to the protein of the oocyte the sperm nucles gets in
3. it makes a corticol reaction and it modifies the ZP and others sperms cannot bind anymore to the ovum

Question 3

primordial cell differentiate in

Answer 3

allantoic ectoderm

Question 4

where does the allantoic ectoderm migrates

Answer 4

migrate to endoderm and then along the hindgut to the genetical ridges

Question 5

how does the migration of the cell occur

Answer 5

migration involves cell protrusion and adhesion in the leading edge and retraction of the lagging edge (repelling and attracting cells)

Question 6

Hormone signal

Answer 6

KITL and KIT
CXCL12 and CXCR4 (GPCR)

Question 7

If you take which hormone signal there would be no more directions

Answer 7

CXCL12 and CXCR4

Question 8

the sequential process of sexual differentiation

Answer 8

• establishment of genetic sex
• translation of genetic sex into gonadal sex
• translation of gonadal sex into phenotypic sex

Question 9

X chromosomes encode more what

Answer 9

gametogenesis and hypothalamus-pituitary functions
and most regulate non reproductive functions

Question 10

Y chromosomes encode more what

Answer 10

regulate reproductive functions

Question 11

sexual differentiation females and males

Answer 11

females: Mullerian duct -> female tract (oviduct, uterus, upper vagina)
males : wolffian duct -> male tract (epididymis, vas deferens, seminal vesicle)

Question 12

what males and females have in common

Answer 12

urogenital sinus

Question 13

urogenital sinus will be .. in females and … in males

Answer 13

clitoris and vulva in females
penis and scrotum in males

Question 14

in male development what will sertoli cells do

Answer 14

mullerian duct regression (AMH)

Question 15

what will leydig cells do in male development

Answer 15

wolffian duct stabilization (source of tetosterone production)

Question 16

after wolddian duct is stablized what happens

Answer 16

male external genital differentiation
testis descent
external genital growth

Question 17

what are the pre requisites for normal sex differentiation

Answer 17

• normal intact chromosome complement
• fully functioning sex determination genes
• intact steroidogenic pathway and receptors

Question 18

true or false
sexual reproduction produces new combinations of genes

Answer 18

true - new combiantions of genes during crossing over at meiosis to produce gametes

Question 19

how does recombinations in sex chromosomes occur

Answer 19

with the PAR (pseudoautosomal region)

Question 20

what contain SRY

Answer 20

MSY - male specific region of Y

Question 21

what happen if a mistake happen and there is a SRY transferred to an X

Answer 21

it would be an XX male

Question 22

SRY makes

Answer 22

male phenotype - testes and external male genitalia

Question 23

if an XY has a deleted SRY

Answer 23

XY female - formation of ovary

Question 24

where does SRY gene binds

Answer 24

to the HMG box and induce transcription

Question 25

if there is +SRY what happens?
Id there isnt an SRY what happens

Answer 25

+SRY: SOX 9 - form Amh (anti mullerian hormone), FGF8, PGD2, other male gene and it will form male

• SRY: foxl2 will make follistatin –> ovarian development

Question 26

how does the anti mullerian hormone signals regress mullerian duct

Answer 26

by the stat jack that will form the SMAD and when it will go to the nucleus it will fr pro apoptotic gene that will program cell death and apoptosis of Mullerian duct

Question 27

what does NR2F2 do in females

Answer 27

signals regression of wolffian duct

Question 28

where is NR2F2 expressed

Answer 28

expressed in mesenchymal cells surrounding Wolffian duct

Question 29

what happens if females embryos are lacking Nr2f2

Answer 29

they will maintain wolffian ducts