Principles of Homeostasis Flashcards
Define Homeostasis
The maintenance of relatively constant conditions in the internal environment
What is the significance of homeostasis in the function of the body?
The body is continually faced with disruptive changes and homeostasis helped to regulate these changes back to a set optimum condition
Homeostasis is the central organising principle through different subject areas
Explain the mechanism of negative feedback and give examples
The response of the system is to oppose the initial change
e.g. body temp, hormone secretion, blood pressure
Explain the mechanism of positive feedback
The response goes the same direction as the initial change
e.g. action potentials, estrogen secretion, labour
Name the 4 major types of cells
Neurons
Muscle cells
Epithelial cells
Connective tissue cells
Define a Cell
Basic unit of life
Define Tissue
Group of cells working together to preform similar functions
Define Organs
Group of tissues working together to preform a similar function
Define Organ System
Group of organs working together to perform a similar function
How is the body’s internal and external environment separated?
Epithelial Tissue
Limitations of homeostasis
Not absolutely constant: small variations and fluctuation
Fever: raised set point
Long exposure to extreme enticements temperatures: the body losses regulatory ability
What parts of the body are classified as the external environment?
Lungs
GI Tract
Kidneys
Explain what the internal environment of the body is?
Internal environment is the immediate environment of most of the body cells
What materials are exchanged between the internal and external environment of the lungs and how?
Simple diffusion of CO2 and O2
What materials are exchanged between the internal and external environment of the gastrointestinal tract (GI tract) and how?
Absorption of water, salts, and nutrients; secretion of acids and proteins
