Embryology

Question 1

Embryology

Answer 1

Study of embryos and their development

Question 2

Gestation

Answer 2

Period of time required for full development of fetus in utero

Question 3

Pre-embryonic stage

Answer 3

First 2 weeks

Question 4

Embryonic stage

Answer 4

3-8 weeks

Question 5

Fetus stage

Answer 5

9 weeks to birth

Question 6

What happens by week 9?

Answer 6

All organ systems are structured

Question 7

Weeks 1-2 of development

Answer 7

• Division, migration, differentiation, gastrulation
• Clinical applications (conditions such as CP)

Question 8

Initial cell divisions

Answer 8

-Fertilization, 2 cell stage, 4 cell stage, 8 cell stage, 16 cell stage (morula)
-Embryoblasts: 70-100 cells (blastocyst), blastocoel by the end of 1st week (cavity forms)

Question 9

When does gastrulation occur?

Answer 9

3rd week

Question 10

Gastrulation

Answer 10

Epiblast and hypoblast cells differentiate into endoderm, mesoderm, and ectoderm. Body axes become visible and cells move towards primitive streak. Ectoderm forms from epiblast

Question 11

Endoderm forms

Answer 11

Epithelial linings of digestive, respiratory, urethra, bladder, reproductive, liver, pancreas

Question 11

Ectoderm forms

Answer 11

Nervous system, epidermis of skin, cornea and lens of eye

Question 11

Mesoderm forms

Answer 11

Notochord, musculoskeletal system, muscle layer of stomach/intestine, circulatory system