Pregnancy test

Question 1

Outline the main stages in in a pregnancy test

Answer 1

1) The wick is soaked in urine, the first urine of the day as this will have the highest levels of hCG

2) The test contains small mobile monoclonal antibodies that have very small coloured beads attached to them
- They only bind to hCG
- If the woman is pregnant then the hCG in the urine binds to the mobile monoclonal antibodies and forms a hCG/antibody complex

3) The urine carries on along the test structure until to reaches a window
4) Immobilised monoclonal antibodies line up as a positive sign

5) The urine travels up to the second window
- Immobilised monoclonal antibodies bind to the mobile antibodies to show that the test is working