Prediction of Elastic Properties of Sperm Flagella

A model is presented for calculating the elastic properties of sperm flagella. The moments and product of inertia of a 9 + 2 axoneme are calculated exactly, and their variation about the center axis is examined. The elastic modulus of microtubule doublets and the central microtubules are calculated from a model discussed elsewhere (Schoutens, 1992). Using these results the flexural rigidity of a 9 + 2 axoneme is calculated. Upper and lower bounds on 9 + 2 axoneme flexural rigidity are calculated, representing the condition in which doublets are connected (upper bound) or completely independent (lower bound). Results from published experimental data are discussed and compared with results obtained in this paper. The elastic modulus, moment of inertia and flexural rigidity agree well with experimentally reported values.