nervous and hormonal system

[hardworker]

Can anyone explain to me how the nervous and endocrine system work in relation to homeostasis. Please

[Yacoubb]

Okay so I'll do it very briefly; this is a very broad topic!

Homeostasis is the maintenance of a relatively stable internal environment of a given organism despite fluctuating external environment conditions. Homeostasis is necessary for the survival of living organisms, as well as the promotion of optimal conditions that enable living organisms to function most effectively.

One thing you need to understanding about detecting and responding to changes is that there are three steps:
(1) Reception:
Specialised receptors are able to detect stimuli and convey information about the stimulus to the integration centre.
(2) Integration centre:
Interprets the information conveyed by the afferent division of the given stimulus, and coordinates a response (i.e. a response to a stimulus; specific).
(3) Along the efferent division, the coordinated response is carried from the integration centre to the effector muscles/glands where a particular response to a stimulus is generated.

The two main organ systems that are involved in the maintenance of homeostasis:
(a) The Nervous System
(b) The Endocrine System

Now, in general, the nervous and endocrine system actually interract with each other in order to regulate (relatively, that is) the internal environment of an organism.

Example: Thermoregulation

* Thermoreceptors detect a drop in core body temperature, and so these specialised receptors convery information about the drop in core body temperature to the central nervous system (i.e. the hypothalamus).
* Neurosecretory cells in the hypothalamus then produce TRH- the neurohormone thyrotropin-releasing hormone. This then travels to the anterior pituitary gland, and the anterior pituitary gland releases TSH (thyroid-stimulating hormone).
* TSH is then carried via the blood-stream from the anterior pituitary gland to the thyroid gland which it acts on.
* The thyroid gland responds to TSH by producing more thyroxine, which increased the rate of metabolism of the living organism.
* Because heat is a by-product of metabolic reactions, the heat elevates core body temperature back up to within the narrow homeostatic range. (negative feedback mechanism - involves counterracting the decrease in body temperature in the opposite direction by producing heat in increased metabolic rate).

^ This shows how both actually work together, especially in negative feedback mechanism. Hope I helped a little bit.