Filopodia-like extensions of the plasma membrane at the apical end of sporozoites. A. Volume rendered representation of the sporozoite shown in figure 2A overlaid with a slice through a tomogram showing an extension of the plasma membrane (blue arrowheads) with electron dense material inside (red). IMC (yellow), polar ring (pink) and microtubules (green) are highlighted. Scale bar: 100 nm. B. A volume rendered representation of the sporozoite from figure 2B showing four extensions of the plasma membrane with material inside. Scale bar: 100 nm. C. Enlarged view of the plasma membrane extensions from panel B and an electron density profile showing distinct peaks for the single leaflets of the plasma membrane (blue arrowheads) and the density inside the protrusion. Scale bars: 100 nm for the micrograph, 50 nm for the profile.