In case anyone was wondering the same: The zinc spark is the release of zinc by the egg upon fertilization. It is called spark because the researchers used a fluorescent probe for detection. There is no light emitted upon conception if the probe is not present. The exact reason for the release of zinc is still unknown.
sunyata
joined 2 months ago
The checkmark marks posts as read. If you want to view posts marked as read you have to enable this in the settings.
Settings > Account preferences > View read posts
There is no shortcut at the top right to quickly toggle or like there is for hidden posts. Not sure why. There is also a button that quickly clears the next 25 read posts. The + at the bottom right also has that button.
Thanks! I corrected it.