Process of internal regulation Flashcards
The body‘s external environment
- This refers to the surrounding environment in which an
organism lives
How can the body cells make vital changes with the external
environment to which they have no contact?
The presence of the extracellular fluid( fluid that surrounds the cells)
Composition of the extracellular fluid
− Plasma : The fluid portion of blood.
− Interstitial fluid : The fluid which surrounds and bathers the cells
What is homeostasis
Refers to the process whereby the body maintains a relatively
stable internal environment
Examples of homoestasis
1.Production of more red blood cells when oxygen levels drop.
2. Thermoregulation
3. Osmoregulation
4. Production of insulin and glucagon to regulate blood glucose levels
Factors that are regulated by homeostasis
*Concentration of nutrients
* Concentration of O2 and CO2
* Concentration of water, salt and other electrolytes.
* Temperature
* pH
* Blood glucose levels
* Blood pressure
* Breathing rate
Digestive system role in homeostasis
- Ingestion
- Breaks down dietary food for
absorption - Egestion
Circulatory system role in homeostasis
- Transportation of materials
Respiratory system role in homeostasis
- Inspiration and aspiration
- Regulation of pH
Urinary system role in homeostasis
- removes excess water, salt,
acid, and other electrolytes
from the plasma and
eliminates them in urine
Muscular system roles in homeostasis
- Assists in thermoregulation
by shivering to produce heat
when the body is cold.
Skeletal system role in homeostasis
- Serves as a storage of calcium
and other minerals. - Production of red blood
cells
The endocrine system role in homeostasis
*Hormones regulate growth, metabolism, electrolyte balances, and reproduction. They ensure that body temperature and electrolyte levels remain within specific limits.
Homeostatic control systems
interconnected networks of body
components that operate to maintain a given factor in the
internal environment relatively constant around an optimal
level
The nervous system role in homeostasis
- Detects changes in the
external environment and
initiates reactions to them
Receptor
sensor that monitors changes in the
environment
Components of the homeostatic control systems
− Receptor
− Control center
− Effector
The control center
determines the level (set point) at which
the variable is to be maintained
The effector
Carrier of the control centers response to the stimulus
Forms of Homeostatic control systems.
−Negative feedback
−Positive feedback
The negative feedback mechanism
In this system, the net effect of the response to the stimulus is
to shut off the original stimulus or reduce its intensity
Positive feedback mechanism
These mechanisms are rare in the body because they tend to
increase the original disturbance and (stimulus) and push the
variable farther from its original value
examples of positive feedback mechanism
- Blood clotting
- Digestion
Homeostatic imbalance
- It is a condition in which humans internal environmental
variables become disturbed
Effects of homeostatic imbalance
- Increased heart beat
- Low blood pressure
- Fast breathing
- Anxiety
- Decreased urine output
- Falls
- High blood pressure
