Figure 1From: The human spermatozoon – a stripped down but refined machineMontage transmission electron micrograph of a human sperm cell. The cell has a compact nucleus, conspicuous mitochondria, no endoplasmic reticulum, minimal cytoplasm and a large tail (about 45 μm in length). Superfluous cytoplasm and associated machinery is jettisoned when the sperm emerges from the testis, leaving a 'stripped down', minimalist cell.Back to article page