Physiology of Homeostasis Flashcards
What is physiology?
The study of how tissues, organs and people function; fundamental to the understanding and practice of clinical medicine
What do we mean ranges?
- Represents what is ‘normal’
- It can tell us if something is abnormal
- Allows suitable control of internal environment
- Humans have dynamic systems, fluctuation is possible
What is homeostasis?
- Regulation of internal environment
- Can occur on many levels including cellular, tissue or whole body
- Usually through communication
What is autocrine communication?
Communication within the same cell
What is paracrine communication?
Communication between neighbouring cells
What is endocrine communication?
Communication between distant cells
What does the negative feedback loop involve?
- Requires 4 separate elements:
1) Stimulus that is detected
2) Internal standard point
3) Output signal in response to change parameter
4) Output activates effector and removes stimulus
What does synergistic mean?
Describes a feedback loop that helps other loops
What does antagonistic mean?
Describes a feedback loop that interferes with other loops, this means that priority and hierarchy
What is the significance of priority and hierarchy?
- Some parameters are more important than others
- Some loops are hierarchical and lead to a cascading effect
What do we mean by redundancy?
- Multiple systems can regulate a given a parameter
- Some pathways become redundant
- Important parameters have multiple systems
- Alternative options, should 1 fail
What is the significance of adaptation and acclimatisation?
- Organisms need to be able to adapt to external environment
- Set point an change to aid this adaptation
- Acclimatisation more long term, involves a more permanent set point modulation
- Alterations possible due to redundancy
