pregnancy tests

    Cards (5)

      1. antibodies complimentary to hCG protein are bound to a coloured bead
    • 2. hCG in urine binds to the antibodies
    • 3. urine moves up the strips carrying beads
    • 4. immobilised antibodies which bind to hCG create the first blue line
    • 5. immobilised antibodies which bind to coloured beads create a second blue line if hCG is present