Craniofacial development

Question 1

when is prenatal development?

Answer 1

1st week

Question 2

when is the embyronic period

Answer 2

week 2-8

Question 3

what is induction?

Answer 3

process where an undifferentiated cell (e.g. mesenchymal cell) is instructed by specific organisers to produce a morphogenic effect.

Question 4

what is cell proliferation?

Answer 4

controlled cellular growth and accumulation of byproducts

Question 5

what is cell differentiation?

Answer 5

change in identical embryonic cells to become distinct functionally and structurally

Question 6

what is cytodifferentiation?

Answer 6

the development of different cell types

Question 7

what is histodifferentiation?

Answer 7

the development of different histological tissue types within a structure e.g. tongue, palate

Question 8

what is morphodifferentiation?

Answer 8

developing of the differing morphology which makes up its structure or shape for each organ or system.

Question 9

what is morphogenesis?

Answer 9

development of specific tissue structure or differing form due to embryonic cell migration and proliferation and inductive interactions

Question 10

what is maturation?

Answer 10

attainment of adult function and size due to proliferation, differentiation and morphogenesis

Question 11

what forms in the 2nd week?

Answer 11

embryonic (germ) cell layers

bilaminar embryonic disk

Question 12

what are the 4 embryonic (germ) cell layers?

Answer 12

ectoderm
mesoderm
endoderm
neural crest cells

Question 13

what is the origin and future structure of the ectoderm?

Answer 13

Origin -> epiblast layer

Future structure -> epidermis

Question 14

what is the origin and future structure of the mesoderm?

Answer 14

Origin -> migrating cells from epiblast layer

Future structure -> dermis, muscle, bone

Question 15

what is the origin and future structure of the endoderm?

Answer 15

Origin -> migrating cells from epiblast layer

Future structure -> respiratory and digestive linings

Question 16

what is the origin and future structure of the neural crest cells?

Answer 16

Origin -> migrating cells from neuroectoderm

Future structure -> nervous system, connective tissue, cartilage, bone

Question 17

what is the bilaminar embryonic disk and what does it develop from?

Answer 17

Is a circular plate of bilayered cells

Develops from blastocyst

Question 18

what happens in the 3rd week of embryonic period?

Answer 18

bilaminar disk thickens and becomes trilaminar embryonic disk

Epiblast layer now considered ectoderm due to development of mesoderm and endoderm

Question 19

what happens in the 4th week?

Answer 19

Embryonic folding -> hard tissue formation starts in response to signals from neural crest cells

Question 20

4th week
what is sequential interaction?

Answer 20

timing of events

Question 21

4th week
what is reciprocal interaction?

Answer 21

one in control of another

Question 22

4th week
what is dynamic interaction?

Answer 22

happens quickly

Question 23

define instructive tissue interactions

Answer 23

one tissue determines the development of another tissue

Question 24

define permissive tissue interactions?

Answer 24

one tissue provides certain conditions required for its partner tissue to progress