Crossword Puzzle Zealous group

Clue: Zealous group

Pair of barbershop groups (OCTET with 5 letters)
Mother's group (DEN with 3 letters)
Mr. T group (ATEAM with 5 letters)
Island group giant tortoises (GALAPAGOS with 9 letters)
Word that describes a group of varying, but related, subjects (UMBRELLATERM with 12 letters)
Group in power (e.g. REGIME with 6 letters)
'50s nostalgia group ___ Na Na (SHA with 3 letters)
Hit-making group? (MOB with 3 letters)
Col. group (FRAT with 4 letters)
Groups of stars? (DREAMTEAMS with 10 letters)