Exploitation competition- Organisms compete indirectly through the consumption of a limited resource.

TLS Online TPP Program

#Id: 7607

#Unit 5. Developmental Biology

TLS Online TPP Program

#Id: 7608

#Unit 5. Developmental Biology

Mutations in either Juno or Izumo block fertilization

TLS Online TPP Program

#Id: 7609

#Unit 5. Developmental Biology

Slow Block to polyspermy

When the cortical granules fuse with the egg cell membrane, they release protein-digesting enzymes that modify the zona pellucida proteins such that they can no longer bind sperm

TLS Online TPP Program

#Id: 7610

#Unit 5. Developmental Biology

Cortical granule proteases is ovastacin When ZP2 is cleaved by ovastacin, it loses its ability to bind sperm

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#Id: 7611

#Unit 5. Developmental Biology

Polyspermy occurs more frequently in mouse eggs bearing mutant ZP2 that cannot be cleaved by ovastacin

TLS Online TPP Program

#Id: 7612

#Unit 5. Developmental Biology

A second slow block to polyspermy comes from the so-called zinc spark, the release of billions of zinc ions that is induced by the entry of the first sperm These released zinc ions are bind to the zona pellucida