FOUND-homeostasis Flashcards
what is homeostasis?
It’s the system that maintains balance and stability between the internal and external environment.
what has to happen when there is hypertension?
Increases in a persons BP should result in a negative feedback loop
which brings blood pressure back down….
Decreasing somebodies BP should result in a reflex increase.
how is long term blood pressure stability maintained?
kidney-renin-angiotensin-ACE system
how us short term blood pressure stability maintained?
adrenal glands release, adrenaline and noradrenaline
how is temperature controlled?
the thermoregulatory system of the hypothalamus
what could occur if temperature is not controlled?
- hyperthermia
- hypothermia
what would be the effectors when too cold?
skeletal muscles-for shivering
which receptors detect temperature change?
peripheral thermal receptors
what would the effectors be when too hot?
sweat glands
what happens when insulin levels fall drastically?
Diabetes (too much glucose)
how are insulin levels detected?
beta cells
what is acidosis?
pH below 7.35
what is alkalosis?
pH above 7.45
what are some symptoms associated with acidosis?
- headache
- confusion
- tiredness
- lethargy and sleepiness
- coughing and shortness of breath
- an uneven or increased heart rate
- stomach upset or feeling sick
- muscle seizures or weakness
- unconsciousness and coma
what are the symptoms associated with alkalosis?
- confusion and lightheadedness
- shaky hands
- numbness or tingling in the feet, hands, or face
- muscle twitches or spasms
- vomiting or nausea
- coma
what are the key detectors of the pH of blood?
chemoreceptors located in blood vessels and brain stem
which molecule is the main regulator in the blood?
HCO3-
what are the 2 main organs that regulate the pH of blood?
lungs
kidneys
how do the kidneys regulate pH of blood?
Excrete acids into urine, produce and regulate
bicarbonate, have slower effects than breathing.
how do the lungs regulate pH of blood?
Exhaling carbon dioxide = rapid changes to blood pH
what receptors are responsible for detecting change in blood osmolarity?
osmoreceptors in the hypothalamus
which hormone is released by the pituitary to increase blood osmolarity?
ADH
what is the narrow range of whole blood osmolarity?
290-300mOsm
what does the blood-brain barrier prevent?
toxins, pathogens, and
other potentially dangerous
substances from crossing from the
circulatory system into the brain
which channels are critical in regulating ionic composition?
aquaporins
