Question

Discuss the mechanisms your body uses to maintain normal water and temperature balance. This answer should include the role of the blood, glands, hormones, organs, etc.

Explain how temperature and humidity affect this.

Answer 1

The mechanisms our body uses to maintain normal water and temperature balance are-:

Water balance- A sensory receptor known as an osmoreceptor which detects changes in plasma osmolarity (concentration of solutes present in the blood) and is primarily present in the hypothalamus of most homeothermic organisms. When the blood undergoes change in osmolarity ( more or less dilute) , the diffusion of water into and out of the osmoreceptors changes. It means, the cells expand when the blood plasma is more dilute and contract when the blood plasma is highly concentrated. When osmoreceptors detect a high plasma osmolarity, then they send signals to the hypothalamus that creates the biological sensation of thirst. These osmoreceptors also stimulate ADH( vasopressin hormone) to initiate the events that would reduce plasma osmolarity to normal levels. Another hormone that induces thirst is through the angiotensin II hormone. This hormone is responsible for maintaining plasma osmolarity and blood pressure.

Temperature balance- Our body regulates the body temperature through a process known as thermoregulation. During this state, the body can maintain a certain temperature, even if the temperature in the surroundings vary. The hypothalamus in the brain regulates the body temperature. If the surrounding temperature increases, then the hypothalamus initiates various processes to lower the body temperature and vice versa. These set of events involve increasing the blood circulation to allow the body surface to dissipate heat through the skin and initiation of sweating to allow evaporation of water from the skin that cools the body surface. Conversely, if the surrounding temperature falls below the core temperature, then the hypothalamus initiates the process of generating heat by shivering. The body uses more energy and generates more heat. Besides, the thyroid hormone stimulates more use of energy and heat production by cells. The evaporation of more sweat takes place in lower humid environment whereas in higher humidity environment the sweat evaporates to a very less extent.