Answer:

ychromosome

Answer	Crossword Clue
YCHROMOSOME	Factor in sex
YCHROMOSOME	Gender-determining heredity unit
YCHROMOSOME	What makes a man a man

YCHROMOSOME	It's a male thing
YCHROMOSOME	He wouldn't be without it
YCHROMOSOME	Male characteristic
YCHROMOSOME	It's a guy thing