The immune system and other factors contribute as control factors also, altogether maintaining constant levels of hormones.

免疫系统和其他因素也作为控制因素发挥作用，共同维持激素的正常水平。

You also need to keep the levels of sugar in the blood constant along with levels of ions and water.

您还需要保持血液中的糖含量以及离子和水的含量恒定。