The force accompanying the movement of Delta into the signaling cell stretches the Notch protein on the responding cell and allowing access by ADAM 10, which cleaves the Notch extracellular domain

TLS Online TPP Program

#Id: 7024

#Unit 5. Developmental Biology

The somatic cells of the hub create asymmetric proliferation by secreting the paracrine factor Unpaired onto the cells attached to them

TLS Online TPP Program

#Id: 7025

#Unit 5. Developmental Biology

Unpaired protein activates the JAK-STAT pathway in the adjacent germ stem cells to specify their self-renewal

TLS Online TPP Program

#Id: 941

#Unit 5. Developmental Biology

 The mode of fertilization in sea urchin being external, the egg and spermatozoa are released into the sea water.

TLS Online TPP Program

#Id: 942

#Unit 5. Developmental Biology

Two major mechanisms during fertilization in sea urchin:

Species-specific sperm attraction 

Species-specific sperm activation

TLS Online TPP Program

#Id: 943

#Unit 5. Developmental Biology

Chemotaxis 

sperms are attracted toward eggs of their species by following a gradient of a chemical secreted by the egg.

TLS Online TPP Program

#Id: 944

#Unit 5. Developmental Biology

In Sea urchin,

Sperm-activating peptides provide direction to sperm during chemotaxis.