CSB328H1 Lecture Notes - Lecture 9: Notch Signaling Pathway, Gsk-3, Glycoprotein

• School: UTSG
• Department: Cell and Systems Biology
• Course: CSB328H1
• Professor: William Navarre

Document Summary

Reading: gilbert chapter 7 (sea urchin section only) Csb328h1 lisa zhao 2013 | page 1. Radial holoblastic cleavage (fig 7. 2, fig 7. 3) Fig 7. 3a black arrow marks site of sperm entry, white arrow marks vegetal pole. Animal tier cells divide meridionally into 8 equal blastomeres (mesomeres) Vegetal tier cells undergo unequal equatorial cleavage into 4 large macromeres & 4 small micromeres: 5th cleavage: 8 animal mesomeres divide equatorially into 2 tiers, an1 & an2 (staggered above each other) Macromeres divide meridionally, forming an 8-cell tier below an2. Micromeres divide unequally into a cluster of 4 small micromeres at the tip of the vegetal pole: 6th cleavage: The small micromeres divide once more, then stop dividing until the larval stage: 7th division: (120-cell) All cells are the same size at the blastula stage. Every cell is in contact w the blastocoel fluid on the inside & the hyaline layer on the outside.