Biology Note
HOMEOSTASIS BIOLOGY I BIO091
Prepared by: Nur Syakireen Bt. Ishak
SCOPE
•Definition and importance of homeostasis •Homeostatic organ •Negative and positive feedback mechanisms •Blood-glucose regulation •Thermoregulation •Osmoregulation
DEFINITON & IMPORTANCE OF HOMEOSTASIS
Homeostasis
• Homeostasis:
• is the steady state of physiological condition of the body. • it is the physiological processes by which organisms maintain a constant & balanced internal environment.
• In achieving homeostasis, animal maintain a relatively constant internal environment even when the external environment changes significantly.
• In multicellular organisms, the internal environment refers to the tissue fluid that baths the cells.
Homeostasis
• Homeostatic mechanisms maintains optimal physical & chemical conditions in the body to allow normal enzymatic & other cellular activities to be carried out.
• This enable the organisms to live in different habitats with a wider
range of environmental conditions.
Homeostasis
• Humans exhibit homeostasis for a range of physical & chemical properties. Examples:
• The body maintains a fairly constant,
• body temperature ~ 37ºC • pH of the blood & interstitial fluid pH 7.4 • level of glucose concentration in the bloodstream ~90 mg of glucose per 100 mL of blood.
• Example of homeostatic organs: skin, liver & kidney.
Mechanisms Homeostasis
• Mechanisms of homeostasis moderate changes in the internal environment. • An animal achieves homeostasis by maintaining a variable (e.g. body temperature or solute concentration) at or near a particular value or set point.
• Fluctuation in the variable above or below the set point serves as the stimulus.
• A receptor, or sensor, detects the stimulus & triggers a response.
• A response is the physiological activity that help return the variable to the set point
Mechanisms Homeostasis
(a) INPUT (Stimulus) (b) Receptor (Sensor) (c) Coordinator
Prepared by: Nur Syakireen Bt. Ishak
SCOPE
•Definition and importance of homeostasis •Homeostatic organ •Negative and positive feedback mechanisms •Blood-glucose regulation •Thermoregulation •Osmoregulation
DEFINITON & IMPORTANCE OF HOMEOSTASIS
Homeostasis
• Homeostasis:
• is the steady state of physiological condition of the body. • it is the physiological processes by which organisms maintain a constant & balanced internal environment.
• In achieving homeostasis, animal maintain a relatively constant internal environment even when the external environment changes significantly.
• In multicellular organisms, the internal environment refers to the tissue fluid that baths the cells.
Homeostasis
• Homeostatic mechanisms maintains optimal physical & chemical conditions in the body to allow normal enzymatic & other cellular activities to be carried out.
• This enable the organisms to live in different habitats with a wider
range of environmental conditions.
Homeostasis
• Humans exhibit homeostasis for a range of physical & chemical properties. Examples:
• The body maintains a fairly constant,
• body temperature ~ 37ºC • pH of the blood & interstitial fluid pH 7.4 • level of glucose concentration in the bloodstream ~90 mg of glucose per 100 mL of blood.
• Example of homeostatic organs: skin, liver & kidney.
Mechanisms Homeostasis
• Mechanisms of homeostasis moderate changes in the internal environment. • An animal achieves homeostasis by maintaining a variable (e.g. body temperature or solute concentration) at or near a particular value or set point.
• Fluctuation in the variable above or below the set point serves as the stimulus.
• A receptor, or sensor, detects the stimulus & triggers a response.
• A response is the physiological activity that help return the variable to the set point
Mechanisms Homeostasis
(a) INPUT (Stimulus) (b) Receptor (Sensor) (c) Coordinator