Embryology

Question 1

Name the 5 subsets of teratogens

Answer 1

physical
chemical
nutritional
hormonal
infection

Question 2

What is the cell mass known as in 0-3 weeks

Answer 2

conceptus

Question 3

what is it called during the 3-8 week period

Answer 3

embryo

Question 4

what is the embryo called from 9 weeks to term

Answer 4

fetus

Question 5

what is an example of a chemical teratogen

Answer 5

smoking or alcohol consumption

Question 6

What are the 6 stages of embryogenesis

Answer 6

gametogenesis
fertilisation
cleavage
gastrulation
morphogenesis
organogensis

Question 7

What happens during cleavage

Answer 7

rapid cell division (no increase in cell size just smaller cells as they divide)

Question 8

What is fertilisation

Answer 8

formation of a diploid zygote

Question 9

What is gastrulation

Answer 9

the conversion of a bilaminar disk to a trilaminar embryo

Question 10

name the three layers formed after gastrulation

Answer 10

endoderm ectoderm and mesoderm

Question 11

what does the endoderm go on to produce

Answer 11

digestive system, liver, pancreas and lungs

Question 12

what does the ectoderm form

Answer 12

skin nervous system hair and nails

Question 13

what does the mesoderm form

Answer 13

circulatory system, skeletal and muscular and epithelial layer of the lungs

Question 14

what is the primitive streak

Answer 14

the first evidence of gastrulation

Question 15

What does the trophoblast differentiate into

Answer 15

cytotrophoblast and syncytiotrophoblast

Question 16

The ventral epiblast and dorsal hypoblast are differentiated from what

Answer 16

embryoblast

Question 17

What is the chorionic cavity formed from

Answer 17

extra embryonic mesoderm cavities

Question 18

Why do the maternal blood vessels rupture

Answer 18

because of the trophoblast embedding in the uterine epithelium

Question 19

What makes up the blastocyst

Answer 19

blastocele (cavity), embryoblast (inner cell mass) and trophoblast (outer cell mass)

Question 20

Around when does the blastocyst come in contact with the uterine wall and implantation occur?

Answer 20

Day 6

Question 21

What is compaction

Answer 21

where the blastocysts are stacked closely with each other

Question 22

Once cell division creates 16 blastomeres, the cell mass is called?

Answer 22

morula

Question 23

What is the zona pellucida

Answer 23

glycoprotein covering the oocyte for protection

Question 24

What attracts the sperm to the ampulla

Answer 24

progesterone and the warmer temperatures

Question 25

What is an ectopic pregnancy

Answer 25

Where the embryo implants outwith the uterine cavity causing an expansion to where the tubes might burst causing a haemorrhage

Question 26

What is capacitation

Answer 26

once the head of the sperm comes in contact with the ZP it releases acrosomes (enzymes) allowing the permeability of the ZP to change and allow better fertilisation with the oocyte

Question 27

What is body folding

Answer 27

the connection of the different layers of the embryo (mesoderm ectoderm and endoderm) to form a 3D morphology/body plan of the embryo

Question 28

What produces the zona pellucida

Answer 28

follicular cells

Question 29

what is organogenesis

Answer 29

the formation of organs and organ systems

Question 30

What is the spermatogonial phase

Answer 30

the mitotic division of the sperm cell into two daughter cells

Question 31

What is the spermatocyte phase

Answer 31

meiosis I and II that eventually produces the four haploid daughter cells (spermatids)

Question 32

What is the spermatid phase

Answer 32

the spermatids differentiate into mature sperms and morphology

Question 33

When does spermatogenesis begin

Answer 33

at puberty

Question 34

meiosis 2 occurs regardless of whether fertilisation occurs

Answer 34

false meiosis 2 occurs only when fertilisation has occurred

Question 35

When does meiosis 2 occur of the oocyte

Answer 35

after capacitation occurs

Question 36

'A mature haploid male or female germ cell which is able to unite with another of the opposite sex in sexual reproduction to form a zygote' A zygote B embryo C gamete D fetus

Answer 36

C gamete

Question 37

Which phase of spermatogenesis involves cell division by mitosis? A capacitation B spermatid phase C spermatocyte phase D spermatogonial phase

Answer 37

D spermatogonial phase

Question 38

When is meiosis complete during oogenesis? A fertilisation B at puberty C just before ovulation D at birth

Answer 38

A fertilisation

Question 39

What does fertilisation achieve? A Stimulates the oocyte to complete meiosis II B Restores a diploid complement of chromosomes (Zygote) C Forms a genetically unique human D Determines sex of the embryo Initiates cleavage

Answer 39

all of the above A B C and D

Question 40

The blastocyst must undergo what process before implantation can take place? A Capacitation B Acrosome Reaction C Hatching D Cleavage

Answer 40

C Hatching

Question 41

What structure forms the embryonic part of the placenta? A Embyroblast B Trophoblast C Yolk sac D Decidua basalis

Answer 41

B Trophoblast

Question 42

Which germ layer would form the following; A skin B lining of GI tract C bone

Answer 42

A ectoderm B endoderm C mesoderm

Question 43

Define the following A. perimetrium B. myometrium C. endometrium

Answer 43

A. the lining surrounding the uterus B. the smooth muscular and thickest layer of the uterus C. the inner-most lining of the endometrium (this lining gets shed if there is no implantation each cycle)