The structural feature of a spermatozoon containing mitochondria arranged in a spiral around the microtubules is the sperm neck. The spermatozoon functions to carry genetic material from the body of a male. It consists of two major parts which are the head and the tail. It is in the tail that the neck is found. This part is a constricted and a short segment. At least two mitochondria can be found in this portion.
