In the sea urchin antibodies to can block mesoderm cell migr
     In the sea urchin, antibodies to  can block mesoderm cell migration.  LH receptors  FSH receptors  Fibronectin  Type 4 collagen  All of these responses  None of these responses  The contractile ring is formed  parallel to centrioles  parallel to the microtubules  perpendicular to the microfilaments  perpendicular to microtubules  mitosis promoting factor is active in  cells in G zero  cells in G one  cells in G two  none of these responses  cytochalasin B disrupts  Karyokinesis  Cytokinesis  Desrnosomes  none of these responses 
  
  Solution
Fibronectin is the extracellular matrix substance that serves in migration of cells by providing them an anchorage for crawling. During migration of mesodermal cells, these fibres serve as the substratum along which the cells migrate. Injection of antifibronectin antibodies to the develpoing embryo disturbs the attachment of migrating cells to the fibronectin and thereby prevents the migration of mesodermal cells. Correct answer is C.

