Science Chapter 3

Chapter 3 :

Coordination and
Response

3.1 ; Homeostasis in Living Things

•Homeostasis is the ability of living systems to maintain a steady and
uniform internal enviroment to allow the normal functioning of the
systems.Example; temperature,water,blood preasure

•If the internal conditions in the body are not balanced,the cells of the
organism may die.

•Homeostasis is important to humans.The most important
homeostasis in human body are regulation of water and body
temperature.



Regulation of Water Content

01 •When we drink water, 02 •Detected by the brain.
water content in the The brain will stimulate
body will increases. the secretion of
hormone.

03 •The kidneys increase 04 •Water content in the
the productiom of urine body decreases.
so more urine is
produced

Regulation of Water Content

01 •Water content in the 02 •Brain will detected
body decreases when and stimulate the
we sweat. secretion of a hormone.

03 •The kidneys will 04 •Water content in the
decrease the body deacreases.
production of urine and
we will feel thirsty.

Regulation of Body Temperature.



Higher Hairs
surrounding lie flat.
temperature.

Lower Hairs
surrounding stand
temperature eract.

Homeostasis in Animals

Homeostasis also occurs in animals.

Example;
•Cat lick it fur to reduce the body temperature
•Dog hang it tongue out so temperature will
decreases.
•Cat fur will stands erect when it is cold to trap
heat.

Reptiles maintain the homeostasis

Cold surrounding Hot surrounding

•body activities become slower •the heart beat faster
•muscles function more slowly •movements become faster
•movements become slower •metabolism rate increase
•metabolism rate decreases •body temperature increases
•body temperature decreases

Homeostasis in Plants ;

Water from plant are lost through a process known as
transpiration. During transpiration,plants lose water from leaves

in the form of water vapour to the surrounding through the
stoma.





Importance of Homeostasis to Human and
Living Things.

•homeostasis in human body and living
things is to provide the optimum
conditions in the body so that cells can
carry out metabolism activities efficiently.

•we should be gratefull.

That’s all

Thankyou ☺

•Nur Najihah
•Adam Idhar