Flashcards in Homeostasis Deck (138)
What happens when the parasympathetic division is activated in initiating feeding?
Feeding behavior is stimulated
What does drinking more water cause in hyponatremia?
Worse conditions. Fave the fluid signal (ADH) mixed with more fluid
A fluid containing solutes
What is lipostatic theory and where can it be seen functioning in the body?
We are sensitive to the amount of fats we have. Receptors in the liver monitor fatty acids
What does the ventromedial hypothalamus do?
Participates in satiety (fullness)
Why do we eat?
Energy and nutrients, pleasure, and complex cultural and psychological factors
How is hyponatremia caused?
Extreme endurance activities caused by low extracellular fluid and low Na
What are osmoreceptors?
Neurons that change firing rate due to water tonicity
What parts of the brain are associated with the hypothalamus?
Infundibulum, anterior pituitary, and posterior pituitary
What does angiotensin II do?
Aids in maintaining blood pressure (tightens blood vessels) and signals the adrenal glands to secrete aldosterone which promotes retention of sodium by the kidneys
Solutions with equal concentrations of solutes. Goal
What leads to hydration?
Water + electrolytes
What percentage of body fluid is intracellular?
What happens with ADH and Na levels in hyponatremia?
ADH is continuously produced which causes water retention and further reduction in Na concentration
What are causes of hypovolemic thirst?
Sweating, vomiting, diarrhea, and blood loss (this is why a cookie and juice is given after blood donations)
Contains warm sensitive (30%), cold sensitive (5%), and other neurons (65%)
Preoptic area of the anterior hypothalamus
What is sensory specific satiety?
When we reject food that's too similar to what we've been having. We want variety
Thirst that is caused by eating. The consumption of liquids while eating
Part of the brain that detects and responds to cooler temps. Shows more neuronal activity when the blood is colder
How is hyponatremia prevented?
Taking in electrolytes during and before extreme endurance activities. Consumption of salty snacks before/during endurance activities
What are prostaglandins?
A product of the hypothalamus that raises our temp set point
What are the mechanisms of hypovolemic thirst?
Results from lower volume of interstitial fluid, blood, or both.
Lower blood volume is sensed by receptors in the heart and kidneys
The wall of the heart muscle contains baroreceptors that measure blood pressure
As blood volume decreases, blood pressure decreases as well
The kidneys contain blood flow receptors that also respond to changes in blood volume
What does hyponatremia cause?
Hypovolemic thirst, cell swelling, severe headache
How is food regulated?
Ebb and flow of nutrient absorption and use (diff patterns in burning energy), short term and long term energy needs (save energy for use later), and body weight set point
Disorder of insulin production diagnosed in childhood or early adulthood
Type 1 diabetes mellitus
What does a lesion to the OVLT cause?
Reduced drinking in response to salty solution
What do kidneys secrete in hypovolemic thirst?
What are the endothermic responses to warm temps?
Perspiration (human default), licking and panting (other animals), and blood vessels dilate near skin surface
What does a constant need for energy with feeding occurring intermittently show?
We have to function in low and high caloric settings