Draw a neat, labelled diagram of a human sperm.
Topic: Human sperm — diagram
Answer
Your diagram must show three regions: • HEAD — with the ACROSOME as a cap at the front and the NUCLEUS filling most of it • MIDDLE PIECE — containing MITOCHONDRIA arranged spirally • TAIL — a long whip-like flagellum (A short NECK joins the head to the middle piece.)
Labels required: acrosome, nucleus, head, neck, middle piece, mitochondria, tail.
THE STRUCTURE-FUNCTION LINK is what the diagram is really testing, and one line beside each label secures the marks: HEAD — carries the genetic material (23 chromosomes, haploid), with the ACROSOME holding the enzyme HYALURONIDASE that dissolves the covering of the ovum so the sperm can enter MIDDLE PIECE — packed with MITOCHONDRIA that respire to supply the ATP for swimming; it is the powerhouse of the sperm TAIL — lashes from side to side to propel the sperm forward
So the sperm is stripped down to three functions: genetic material, energy, movement. It carries almost no cytoplasm, which keeps it light and fast — the opposite of the ovum, which is large and full of stored food.
Draw it large and in proportion: the tail should be much the longest part.