Embryological basic Definitions Flashcards
Growth
The increase in size or number of cells
Accretion
The growth of an extracellular matrix
Differentiation
Totipotent cells become a certain cell type
Organisation
Cells become organised into a certain pattern or formations
Induction/Morphogenesis
Signals from neighbouring cells influence the development of adjacent cells
Gastrulation
The formation of three layered structure:
Ectoderm
Mesoderm
Endoderm
Primitive node and Primitive streak
The formation initiates gastrulation
Notocord
This arises from the mesoderm and causes the formation of the neural plate and then the neural tube
Ectoderm and what does it form?
The outer layer
- Skin Nervous System
- Retina
Mesoderm and what does it form
The middle layer
- Bone
- blood (heart)
- Muscles
- excretory organs (kidneys)
- Adrenal cortex
Endoderm and what does it form?
Inner layer and it forms anything that has an external surface
- GI tract
- Respiatory tract epithelial cells
- stomach
- colon
- liver
- pancreas
- bladder
- thyroid
- parathyroid
Syntiotrophoblast
This becomes the placenta
What is neuralation and how does it start?
Formation of neural tube with the notocord
What does gastrulation begin with?
Formation of primitive streak
Where does the primitive streak come from?
Epiblast
What does endoderm form form?
Hypoblast
What is dorsal to the epiblast?
Amniotic cavity
