embryonic development weeks 1-3

Question 1

where are the enzymes are in the head of the sperm

Answer 1

acrosome

Question 2

where is the mitochondria of sperm located

Answer 2

middle piece

Question 3

capacitation

Answer 3

glycoprotein coat and seminal plasma proteins removed from plasma membrane of sperm. this part happens in uterus
passage of sperm through corona radiata-hyaluronidase

Question 4

passage of sperm through corona radiata

Answer 4

hyaluronidase. part of step 1

Question 5

penetration of zona pellucida

Answer 5

esterases, acrosin, neuraminidase. zona reaction- block to polyspermy

Question 6

step 3 of ferltilization

Answer 6

fusion of plasma membranes of oocyte and sperm. head and tail of sperm enter oocyte cytoplasm

Question 7

step 4 of fertilization

Answer 7

completion of second meiotic division. formation of male pronucleus. fusion of male and female pronuclei. (zygote)

Question 8

trophoblast gives rise to

Answer 8

cytotrophoblast and then syncitiotrophoblast

Question 9

cytotrophoblast

Answer 9

stem cell layer for placenta. mitotically active

Question 10

syncytiotrophoblast

Answer 10

proteolytic enzymes, chorionic gonadotropin, responsible for implantation and initial signal of pregnancy

Question 11

hydatidiform mole

Answer 11

complete mole from fert. of an empyt oocyte and duplication of sperm or fert. of an empty with two sperm.
partial mole results from fert. of a normal oocyte by two sperm

Question 12

inner cell mass differentiates to two types of cells

Answer 12

epiblast, and hypoblast

Question 13

epiblast

Answer 13

ectoderm, amnion, amniotic cavity

Question 14

hypoblast

Answer 14

extra embryonic, never incorporated into the embryo. job is to signal and placehold

Question 15

hypoblast endoderm

Answer 15

prechordal plate, primary and secondary yolk sac (umbilical vesicle), extraembryonic mesoderm

Question 16

extraembryonic mesoderm

Answer 16

coelom (cavity outside of embryo), somatic mesoderm (lining of trophoblast and amnion), splanchnic (lining of yolk sac)

Question 17

derivatives of extraembryonic mesoderm

Answer 17

connecting stalk (umb cord) (somatic)
primitive blood (splanchnic)
chorion (layer of plcenta) (somatic mesoderm and cyto and syncytiotrophoblast)

Question 18

gastrulation

Answer 18

form 3 germ layers (ectoderm, mesoderm, endoderm)

Question 19

notochord

Answer 19

template for vertebral column. induces neural plate and CNS formation

Question 20

chordomas

Answer 20

arise from remnants of notochord. neoplasm of bone.

Question 21

mesoderm

Answer 21

paraxial-somites (muscle, skeleton, dermis)
intermediate-urogenital (kidneys and gonads)
lateral plate-connective tissue (blood, lymph, mesenteries, cardiovascular)

Question 22

ectoderm

Answer 22

outer skin, hair, nails, cns

Question 23

mesoderm

Answer 23

structure, support, muscle, bone, blood, heart, connective tissue, dermis of skin, urogenital, kidneys

Question 24

endoderm

Answer 24

lungs, lining digestive, bladder, liver, pancrease