27. Homeostasis Flashcards
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What is homeostasis?
The condition of a relatively stable internal environment, maintained within narrow limits, in the face of external change.
What is the condition of a relatively stable internal environment, maintained within narrow limits, in the face of external change.
Homeostasis
What is the prefix for “above normal”
Hyper
What is the prefix for “below normal”
Hypo
What does NAD mean?
No abnormalities detected
What is the abbreviation for no abnormalities detected
NAD
What is the abbreviation for within normal limits?
WNL
What does WNL mean?
Within normal limits
What is a key term when discussing how systems maintain homeostasis?
Regulate
What does the term regulate mean?
To make changes to ensure things are within normal limits
What is meant by negative feedback loop?
The response to stimulus is in the OPPOSITE direction
eg. is something is increasing, the reaction will be to decrease
Would you shiver or sweat in response to hyperthermia and why?
sweat - to decrease body temp
sweat = heat loss via evaporation
Would you shiver or sweat in response to hyporthermia and why?
shiver - to increase body temp
Shiver = heat generation via movement
Would you experience vasodilation or vasoconstriction to the organs in response to hyperthermia and why?
Vasoconstriction - as blood needs to be redirected to the skin to cool down
heat loss to skin via radiation
Would you experience vasodilation or vasoconstriction to the skin in response to hypothermia and why?
Vasoconstriction - as blood needs to be redirected to the organs to maintain heat
heat loss to skin via radiation
Would you experience vasodilation or vasoconstriction to the skin in response to hyperthermia and why?
Vasodilation - as blood needs to be redirected to the skin to cool down
heat loss to skin via radiation
Would you experience vasodilation or vasoconstriction to the organs in response to hyporthermia and why?
Vasodilation - as blood needs to be redirected to the organs to maintain heat
heat loss to skin via radiation
Do you exeprience pilo erection during hyperthermia or hypothermia?
Hypothermia - hairs on skin erect to trap heat
heat loss via radiation
Is insulin or glucagon released in response to hyperglycaemia and why?
Insulin - increases blood glucose uptake as glycogen into cells
decreases BGL
Is insulin or glucagon released in response to hypoglycaemia and why?
Glucagon - as it breaks down stored glycogen into blood glucose
increases BGL
Does ADH release increase or decrease in response to low blood volume and why?
increase - to increase water absorption into the blood increasing blood volume
Does ANP release increase or decrease in response to high blood volume and why?
increase - to decrease salt and water absorption into the blood decreasing blood volume
Does aldosterone release increase or decrease in response to low blood volume and why?
increase - to increase salt and water absorption into the blood increasing blood volume
Does high blood volume lead to high or lower blood pressure?
High
Does low blood volume lead to high or lower blood pressure?
lower
What is the most potent way to regulate blood ph?
Buffer system
regulation within the blood
Which system is the buffer system part of?
Cardiovascular
How does the respiratory system help regulate ph?
Through respiratory rate
CO2 removed through expiration
How does the urinary system help regulate ph?
Through secretion in the nephron/kidney/urine formation
H+ions removed from urine in distal tubule
What is the name of the sensory receptor for temperature?
thermoreceptor/s
What is the name of the sensory receptor for blood pressure?
baroreceptor/s
where can we find thermoreceptors?
in the skin, in the hypothalamus
where do we find baroreceptors?
in the carotid arteries and the Aorta
What is the name of the sensory receptor for fluid balance/blood volume?
osmoreceptors
where do we find osmoreceptors?
Hypothalamus
Would you experience vasodilation or vasoconstriction in response to hypertension and why?
vasodilation to increase diameter of lumen, to reduce pressure on artery walls (reduce artery wall stretch) thereby reducing BP
Would you experience vasodilation or vasoconstriction in response to hypotension and why?
vasoconstriction to decrease diameter of lumen, to increase pressure on artery walls (increase artery wall stretch), thereby increasing BP.
Does Cardiac Output (Q) increase or decrease in response to hypertension? Why?
Cardiac output would decrease to reduce artery wall stretch/ reduce BP
Does Cardiac Output (Q) increase or decrease in response to hypotension? Why?
Cardiac output would increase to increase artery wall stretch/ increase BP.
How do we calculate Cardiac Output?
Stroke Volume (SV) x HR
To increase Q (cardiac output) do HR and SV increase or decrease?
both increase
To decrease Q (cardiac output) do HR and SV increase or decrease?
both decrease
If a pt is experiencing acidosis (low blood pH), will RR increase or decrease? Why?
increase to increase amount of CO2 being expired/removed from blood
If a pt is experiencing alkalosis (high blood pH), will RR increase or decrease? Why?
decrease to reduce amount of CO2 being expired/removed from blood
If a pt is experiencing acidosis (low blood pH), will the buffer system remove more or less Hydrogen (H+) ions?
will remove more.
If a pt is experiencing acidosis (low blood pH), will the urinary system remove more or less Hydrogen (H+) ions in the secretion stage of urine formation?
will secrete more H+ ions from the blood into the urine to be excreted
