Bekhorot 43: three things to remember

Priests with full blemishes profane the service, bodily anomalies violate a positive command, while mere unsightly traits carry only rabbinic bans.
Superfluous verses link human and animal blemishes, while distinct verses are required because priests, sacrifices, and firstborns possess unique sanctities.
A gibben is a priest lacking eyebrows or having a severely crooked spine, and a flat-nosed priest is disqualified from service.