MINISTRY OF DEFENCE

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  MINISTRY OF DEFENCE. Establishment Of National University In Islamabad Total position. 29 Domicile , All over Pakistan    Qualification  intermediate to bachelor positions . Project Engineer(Civil) account Officer  supervisor assistant office boy     How to apply.   Apply online through the link https://www.fgei-cg.gov.pk/nup-rec.php   Last date to apply  02 April 2023. No TA/DA Fo Interview 
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Homeostasis,Aspect Of Homeostasis,feed back system and water relations of cell


What is homeostasis and what are the important aspect of homeostasis?

Homeostasis

(Homo=same stasis= condition) Homeostasis is the maintenance of the internal environment of the body. It has 3 aspects

1. Osmoregulation:

Maintenance of water and solutes in the body.

2. Thermoregulation

(Thermo =temperature)
In thermoregulation temperature is regulated till suitable limit.

3.Excretion:

(Removal)
In excretion unwanted,nitrogenious waste and toxic material are removed from the body.

Feed back system

Many physiological processes take place in the body to maintain homeostasis, In homeostasis there is a check and balance system,which maintain the homeostasis, Called feedback system.

 Types of Feed Back System

1. Negative feed back


This is opposite reaction due to any change in the body fluid,for example when we take more sugar in diet,so our glucose level increase and message is transferred toward the CNS,CNS analysis and transfer message toward the Pancreas,From the Beta cell of pancreas insulin is secreted into blood and extra amount of glucose sn stored in Muscle and Liver in the form of Glucogen. When glucose level decrease so Alpha cell of Pancreas secrete Glucagon hormone into blood and glycogen from liver and muscle is converted into glucose.

2. Positive Feed Back

When there is a change in the internal body system and this is further increased by a process,it is called positive feedback.
For example in warm blooded animals when internal body temperature is increased die to heat stroke,the body temperature is further increased,this is positive feed back, it may be useful in some and harmful for other conditions.

Water Relations Of Cell:

Water acts as a biological solvent because takes part in metabolic activities of a cell. Water moves in and out of cell by a process called Osmosis, in osmosis water moves from higher concentration toward the lower concentration through the cell membrane.
When a plant Cell is kept in hypotonic solution (solution has more water than cell), water continuously moves inside the cell called endoosmosis and by this process cell becomes turgid and does not burst because cell wall causes Pressure Potential,which avoid further movement of water inside the cell. When plant cell is kept in hypertonic solution(more concentrated than cell ),water moves outside to inside by a process called exoosmosis due to this the cytoplasm of cell shrinks from the cell wall, process is called
Plasmolysis

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