Introduction to Embryonic Development

Question 1

What is the chorion?

Answer 1

Extra-embryonic mesoderm + Cytotrophoblast + Syncytiotrophoblast

Question 2

What are the three parts of the primitive streak?

Answer 2

Primitive node, primitive pit, primitive groove

Question 3

What part of the primitive streak is closest to where the head will form?

Answer 3

Primitive node

Question 4

What is the notochord?

Answer 4

It is a hollow tube that forms the vertebral column and the nucleus palpopus (jelly inside discs)

Question 5

What is the temporary connection between the amniotic cavity and yolk sac?

Answer 5

Neurenteric canal

Question 6

What is a teratoma?

Answer 6

All three germ layers together in a tumor

Question 7

What is derived from the surface ectoderm?

Answer 7

Epidermis, hair, nails, sweat and sebaceous glands

Epithelium of lower anal canal, distal part of male urethra, external auditory meatus

Question 8

What is derived from the neural ectoderm?

Answer 8

CNS

Question 9

What is derived from the neural crest?

Answer 9

PNS and other special structures

Question 10

What is derived from the mesoderm?

Answer 10

All connective tissues and muscles and serious linings of body cavities; Kidney adrenal cortex and gonads

Question 11

What function does the neurenteric canal serve?`

Answer 11

It keeps pressure between the yolk sac and amniotic cavity constant

Question 12

What forms the neurenteric canal?

Answer 12

Notochord and endoderm caudally fused