Answer: Maternal anti-Rh antibodies cross the placenta and destroy foetal red cells.
- A The foetus makes anti-Rh antibodies
- B Maternal anti-Rh antibodies cross the placenta and destroy foetal red cells
- C The mother lacks all clotting factors
- D The foetus lacks haemoglobin
Correct answer: B. Maternal anti-Rh antibodies cross the placenta and destroy foetal red cells
Explanation: After sensitisation in a first pregnancy, the Rh-negative mother produces anti-Rh antibodies that cross the placenta and haemolyse the Rh-positive foetal erythrocytes.
A single ECG cycle: the P wave marks atrial depolarisation (contraction signal), the large QRS complex marks ventricular depolarisation, and the T wave marks ventricular repolarisation (recovery) before the next cycle begins.
Concept context
Blood, lymph, the heart, the cardiac cycle, blood pressure, and ECG. High NEET weightage.