Possible Clues:

• Toadstool
• A mushroom, toadstool or mould
• Mould, for example
• 'What gives me a funny turn outside Wolfson's concern? The loo!' (12s)
• That's a mouldy sort of sport to have with a boy (6)
• Mushroom such an organism
• Mouldy sort of sport with a boy
• One as yeast, mushroom
• Just for sport, the boy gets moulded
• How one of 27 across have some sport with the boy