No, the absence of air cells in the ethmoid bone would not make the skull too heavy. The ethmoid bone primarily serves as a structural support and does not significantly contribute to the overall weight of the skull. The function of the ethmoid bone is mainly related to the structure of the nasal cavity and the support of the brain and its surrounding structures. The absence of air cells in the ethmoid bone may affect its function in filtering and humidifying air, but it would not make the skull excessively heavy.
