Answer: 1. The first stage is when the neck of the womb (cervix) opens to 10cm dilated. The second stage is when the baby moves down through the vagina and is born. The third stage is when the placenta (afterbirth) is delivered. 2. Drugs or medication taken by the mother may cross the placenta and reach the developing fetus. The possible effects may include developmental delay, intellectual disability, birth defects miscarriage and stillbirth. 3. The pneumococcal conjugate vaccine (PCV13) and the pneumococcal polysaccharide vaccine (PPSV23) protect against pneumococcal infections. The bacteria that cause these infections spread through person-to-person contact. They can lead to serious infections like pneumonia, blood infections, and bacterial meningitis.
Explanation:
Answer: Spleen
List of the organs in the immune system:
Lymphoid
Thymus
Lymph nodes
Slpeen
Lymphatic
