Embryology

Question 1

How long is the embryonic period?

Answer 1

8 weeks

Question 2

What takes place during the embryonic period?

Answer 2

Fertilisation - fusion of sperm and oocyte to form zygote
Clevage - rapid cell division -> blastocyst
Gastrulation - germ layers formation (from primitive streak)
Organogenesis - organs and organ systems formed
Foetal Period - growth and weigh gain

Question 3

What is epigenetic control of development?

Answer 3

preferential expression of either maternal or paternal copies of genes

Question 4

TERMINOLOGY - in the adult it is posterior, what is it in the embryo?

Answer 4

dorsal

Question 5

TERMINOLOGY - in the adult it is anterior, what is it in the embryo?

Answer 5

ventral

Question 6

TERMINOLOGY - in the adult it is superior, what is it in the embryo?

Answer 6

cranial

Question 7

TERMINOLOGY - in the adult it is inferior, what is it in the embryo?

Answer 7

caudal

Question 8

Where does fertilisation take place?

Answer 8

ampulla

Question 9

Where does implantation occur?

Answer 9

uterine cavity - driven by trophoblasts

Question 10

What are the germ layers

Answer 10

Ectoderm
Mesoderm
Endoderm

Question 11

What does the ectoderm form?

Answer 11

epidermis of skin and nervous system

Question 12

What does the mesoderm form?

Answer 12

paraxial: axial skeleton, voluntary muscle
intermediate: urogenital systems - kidney and ureter
lateral plate: lining of the body wall and cardiovascular system

Question 13

What does the endoderm form?

Answer 13

lining of the gut tube and respiratory tract