- Hormone: Estrogen.
- Source organ: Ovaries (developing follicles).
- Event: Estrogen helps repair and thicken the uterine lining (endometrium) that was shed during menstruation, preparing it for potential implantation.
(a) Why do the symptoms of malaria not appear in a person immediately after being bitten by an infected female Anopheles? Give one reason. Explain when and how do the symptoms of the disease would appear.
A certain reaction is 50 complete in 20 minutes at 300 K and the same reaction is 50 complete in 5 minutes at 350 K. Calculate the activation energy if it is a first order reaction. Given: \[ R = 8.314 \, \text{J K}^{-1} \, \text{mol}^{-1}, \quad \log 4 = 0.602 \]