5. In some countries some women are paid to donate eggs that scientists can use in their studies on fertilisation. Is this a good idea? Explain your answer. o the uterus. 6. Some mothers have twins that are not identical. Suggest how this happens.

In many cultures, the practice of paying women for egg donation has sparked debates on ethics, consent, and commodification of human life. Supporters argue that it can help many couples struggling with infertility and contribute to valuable scientific research. However, opponents express concerns over the potential exploitation of women, particularly those from lower socio-economic backgrounds, and emphasize the need for regulated practices to ensure ethical treatment and informed consent. Non-identical twins, also known as fraternal twins, occur when a woman releases two eggs during her ovulation cycle, and both are fertilized by different sperm. This can happen naturally or through assisted reproductive technologies like fertility treatments. Unlike identical twins, who result from a single fertilized egg splitting into two embryos, fraternal twins carry different genetic makeups, which is why they may not look alike and can even be of different sexes! How fascinating is that?