The nervous system, in particular a part of the brain called the hypothalamus, controls thirst.
The hypothalamus is the part of the brain that controls body temperature, as well as other things like thirst, hunger, and the release of many hormones.
The hypothalamus is the part of the brain that controls rage, pleasure, hunger, thirst, and sexual desire. It plays a key role in regulating basic survival functions and the release of certain hormones that influence these behaviors.
The hypothalamus controls body temperature. It links the nervous system to the endocrine system. The hypothalamus controls body temperature, hunger, thirst, fatigue, and circadian cycles.
Hypothalamus
The brain stem is the part that controls breathing, it is the stem that allows the respiratory system to work and help you breathe
The hypothalamus is the part of the brain that controls fluid intake. It regulates thirst by sensing changes in blood volume and osmolality, signaling the body to drink more water if needed.
brain stem
The part of the brain called the Cnifiliatispin controls all testing of heat conditions.
To the extent that there can be said to be such a thing as a "part of the brain that controls hope", it's probably the prefrontal cortex.
brain stem
Action potential in the brain