Principles of Homeostasis Flashcards
Compensation
return to homeostasis after being challenged
Decompensation
The failure to compensate, adapt heal etc
What happens if you end up with too little water in the body?
The osmolarity of the plasma in the interstitial fluid changes and this is detected by osmoreceptors in the hypothalamus
What is triggered when the osmoreceptors are stimulated
The pituitary gland, this then releases ADH (antidiuretic hormone)
What is the effect on the salivary glands when there is too little water?
1) triggers thirst
2) Stickier saliva
How is the blood pressure effected when there is too little water?
When there is too little water, blood pressure drops therefore signals go to the heart to incresae the rate of contraction
Juxta-Glomerulus apparatus
A group of cells next to the kidney that activtae the RAAS pathway this leads to increased retention of sodium in the kidneys
What happens when calcium in the blood drops?
It is detected by the parathyroid gland which then releases parathyroid hormone and attempts to boost levels of calcium in the blood
Osteoclasts
cells which break down bone, can be stimulated by parathyroid hormone
Calcitonin
Stimulates the storage and excretion of calcium
How is aging an example of homeostasis?
Over time there are more mutations to cells so the body employs corrective mechanisms such as increased chaperone proteins
What are some examples of positive feedback?
Increased oxytocin causing parturition (contractions) or digestion of proteins
What is the function of Calcitonin
Causes the kidney to take up less calcium and increases calcium deposition in bones
What do Chaperone proteins do?
Regulate protein folding/ Misfolding
What occurs when you have an allergy?
More villi cells from the crypt are broken down by apotosis than produced so over time the villi are worn down in the intestine
