Linked from
The 8 pages that link to Antiquark, each with the reason it gives.
Quark modelBroader topic: Antiquarks pair with quarks to form mesons in the model.
MesonBroader topic: An antiquark pairs with a quark in the conventional meson structure.
Baryon numberRelated: An antiquark contributes −1/3 to baryon number.
AntiprotonBroader topic: Two anti-up quarks and one anti-down quark make an antiproton.
PentaquarkRelated: Every pentaquark contains one antiquark alongside four quarks.
AntineutronBroader topic: Three antiquarks make up an antineutron.
Down quarkCompared with: The down antiquark reverses the down quark’s electric and color charges.
TetraquarkRelated: Most observed tetraquark candidates combine two quarks with two antiquarks.