• Question: what is the normal size of a sperm and blood cell

    Asked by Philip to Callum, Gina, Katie, Michelle, Sam on 15 Nov 2012.
    • Photo: Michelle Linterman

      Michelle Linterman answered on 15 Nov 2012:

      Hi Phillip,

      The cells in your blood a pretty small, they are about one tenth the width of a human hair (7-15 microns).
      The head of a sperm is slightly smaller than a blood cell (5 microns). By contrast the egg produced by human females is the biggest cell made by humans, you can see it with a naked eye, just, it is about the size of a full stop, or the same as the width of a human hair.

      Let us know if there is anything else!
      Michelle

    • Photo: Katie Howe

      Katie Howe answered on 16 Nov 2012:

      Hi Phillip,

      Michelle gave a great answer above.

      Another interesting thing is that the bigger the animal is, doesn’t necessarily mean it will have bigger sperm cells….

      For example the blue whale (which is the biggest animal on the planet) has sperm cells which are roughly the same size as human sperm. And in contrast the tiny fruit fly has massive sperm of about 2mm in size! The fruit fly sperm have a super long tail which is helpful for stopping other sperm reaching the egg.

      Thank you for your question!

Comments