Propagation: Jiffy Mini-Greenhouse for starting seeds, 1 by SuzyQu

SuzyQu wrote:
Greetings! I signed up for this forum in the hopes of getting as much feedback as I can.
I'm brand new to germinating my own seeds and have a little mystery.
I have a tray of different seeds germinating in little cups (that will turn into compost when planted).
I have been finding these golden colored balls in my seed cups. At first I just pinched them between my fingers and they burst.
Then I thought, well maybe my seeds have a disease.
And finally I thought, 'is this the process of seed germination?"
I'm including a pic of my tomato plant and you can see a golden round little egg-like ball (my mint also has one of these balls).
What the heck is this?
Thanks for your feedback!!