Fig. 4. Representative examples of the effects of salivary gland homogenate on sporozoite motility. (A) Random sporozoite motility in Matrigel. (B) Directed sporozoite motility in the presence of salivary gland homogenate. X–Y (upper left), X-time (bottom), and Y-time (upper right) maximum projections of 60 time-lapse images acquired over a 318 s period. The yellow outlined arrows show the directions of sporozoite movement (green). To highlight the influence of time on sporozoite direction, the yellow broken lines indicating the starting and ending points of a sporozoite moving in X–Y space were projected into both X- and Y-time space to demonstrate the influence of time on motility. The solid yellow arrow in B indicates the relative position of the salivary gland homogenate.