Homeostasis Flashcards
(45 cards)
What is the definition of homeostasis?
A condition of equilibrium (stability or balance) in the body’s internal environment in response to a stimulus via receptors. This system works to keep the body within the limits to maintain optimum cellular activity.
What does the pH of blood usually stick between?
7.35-7.45
What are the two main systems in the body that contribute to homeostasis?
The nervous and endocrine systems
What are the components of a feedback system?
- Stimulus
- Receptor/sensor
- Control centre
- Effector
What is the stimulus in a feedback system?
Any disruption to a controlled condition
What does the receptor/sensor do in a feedback system?
Monitors the environment and responds to a stimulus
What does the control centre do in a feedback system?
Determines set-point/range to be maintained
Analyses input and determines the appropriate response (output)
What is the role of the effector in a feedback system?
It involves muscles or glands which bring about a response or effect
Define Disease
Any failure of normal physiological function leading to negative symptoms
What factors are necessary for homeostasis?
Effective receptors
Effective brain function
Effective major organs
An adequate blood volume
More specific
- Effective blood vessels
- An effective cardiac pump
- Effective kidney function
What are the role of Baroreceptors?
The baroreceptors send signals to the brain and the signals are interpreted as a rise in blood pressure.
What are the role of chemoreceptors?
The chemoreceptors transmit nervous signals to the respiratory center in the brain to help regulate respiratory activity.
What are the role of Mechanoreceptors?
Mechanoreceptors respond to physical forces in touch, hearing, and pressure
What are the role of Nocireceptors?
Nociceptors are sensory receptors that detect signals from damaged tissue or the threat of damage and respond to chemicals released from the damaged tissue.
What is the role of Photoreceptors?
Photoreceptors are specialized neurons found in the retina that convert light into electrical signals that stimulate physiological processes
What is the role of Thermoreceptors?
Thermoreceptors give the body the ability to detect heat and cold in the environment.
Abnormal vital signs = what?
A change in homeostasis due to an acute situation or chronic disease process
What is negative feedback?
Feedback which prevents sudden severe changes within the body ie, reverses or negates original stimulus. Once equilibrium is achieved this responses is reduced and “Shuts off”
What is positive feedback?
These enhance and amplifies an effector of a change in order for the response to continue at a faster rate. This loop only stops when the stimulus is removed.
Which are more common, positive or negative feedback loops?
Negative
Which feedback loop works to maintain equilibrium? Positive or Negative?
Negative
Which type of diabetes is NO insulin produced?
Type 1 diabetes
How does homeostasis balance BGLs?
A rise in blood glucose levels above a set point causes a receptor to make insulin-secreting cells in the pancreas, insulin is released into the blood allowing for glucose to be absorbed by the blood and removed from the body causing BGL levels to return to normal.
What does the term hyperglycaemia mean?
This is where the level of sugar in your blood is too high. It mainly affects people with diabetes and can be serious if not treated.
