Why Study Sea Urchins?
Introduction
Shedding gametes
The Acrosome Reaction
Normal Fertilization - Overview
Fast Block to Polyspermy
Slow Block to Polyspermy - Classic Studies
Slow Block to Polyspermy - Cortical Granules
Egg Activation - The Role of Calcium
Egg Activation - Signal transduction leading to calcium release
Introduction
Cleavage - Representative Stages
Radial Cleavage
Reductive Cleavage
Cleavage - Mechanism
Alteration by Compression
Fourth Cleavage
Blastula Structure
Introduction
Morphogenetic Movements
More Movements
Ingression of PMCs
Adhesive Changes during PMC Ingression
Classic footage of PMC Ingression
Invagination of the Vegetal Plate
Models of Primary Invagination-I
Models of Primary Invagination-II
Evidence for Apical Constriction
4D Analysis of Primary Invagination
Secondary Invagination
Secondary Mesenchyme Filopodia
Secondary Mesenchyme Exert Tension
Autonomonous Extension in Exogastrulae
Laser Ablation of Secondary Mesenchyme
Convergent Extension
Studying Convergent Extension-I
Studying Convergent Extension-II
Summary of Secondary Invagination
The Role of the Extracellular Matrix
The Role of the Apical Lamina
The Role of the Hyaline Layer
The Role of the Basal Lamina
Introduction
Using Radialized Embryos
PMC Transplants-I
PMC Transplants-II
Secondary Mesenchyme-I
Secondary Mesenchyme-II
Secondary Mesenchyme-III
Secondary Mesenchyme-IV