Homeostasis

Homeostasis and Osmoregulation

Homeostasis and Osmoregulation

Introduction

Homeostasis is the set of phenomena that lead to self-maintenance of constancy in the properties and composition of the internal environment of an organism. This term transcends biology to refer to the characteristic of any system, either open or closed, allowing you to regulate the internal environment to maintain a stable condition. Stability is possible by different mechanisms of regulation and various dynamic adjustments (Cannon, 2003).

Biological homeostasis, therefore, consists in a dynamic equilibrium is reached thanks to constant changes to maintain the result of the assembly. This process involves monitoring the energy values ??that are considered normal: if a value is outside the normal, different mechanisms are activated to compensate. Homeostasis of the organism depends on the internal environment (with the production and disposal of certain substances, for example, through the urine) and the external environment (the ratio of the living being and the environment) (Marieb & Hoehn, 2007).

Discussion

Osmoregulation, the ability of all living beings with a metabolism to be able to control the concentrations of osmotically active substances, either to avoid osmotic stress (eg, by polymerization of glucose to the osmotically neutral macromolecules starch or glycogen) (Solomon, Berg & Martin, 2002). It may also be seen from the osmotic potential, which always occurs on membranes to benefit, for example ANansportprozesse. Important here are K + ions (potassium), Ca 2 + (calcium ion) and H + (proton) (Marieb & Hoehn, 2007).

To increase the blood pressure initially the hypothalamus produces a hormone called ADH, which is to be stored within the pituitary. Once the body senses the need to increase blood pressure causes the hypothalamus and the pituitary sends ymetrolinfa chocolinfa proteins, which give an order to release ADH (Cannon, 2003). When this hormone is released is directed toward nephron, functional unit of the kidneys to increase its level of permeability, apart from a vasoconstriction of the arteries (ie the press, so that the pressure increases). The pituitary in turn also creates its own hormone, ACTH, which like the ADH will address the kidney (specifically the adrenal glands). Once the ACTH reaches the gland, this to be stimulated release another hormone aldosterone, which stimulate the kidney to retain calcium which would be brought into the urine, and transitions to the blood, which also favors an increase in pressure. If you need the latter process remains the same kidney produce an enzyme called renin, which in turn form angiotensin II, which will target the adrenal glands to keep the cycle going (Solomon, Berg & Martin, 2002).

Plants are able to respond to a change in qualitative or quantitative supply of water via O. to react. In addition to the specialized halophytes also meet Glykophyten to some extent the stress of increased salt concentrations in the substrate or modified by specific action, and include others in the plasma ion uptake or passing into the vacuole, and the synthesis of osmotically active proteins. Water shortages may, by reducing the diffusion at the stomata and by Turgorabsenkung by water leakage from the vacuoles ...