Chapter 11: Hydration | Lesson 1: The Physiology of Hydration Flashcards
(21 cards)
What does water do in the body?
It helps fill the space inside of cells, outside of cells, and in all major vessels.
How much does water fluctuate daily with a person who does very little activity?
Very little
How much of the total water in a body is inside the cells?
2/3rds
What is fluid inside the body called?
Intracellular fluid (ICF)
Where is the remaining 1/3rd of fluid outside of the cells?
In the blood plasma and space between cells
What is the technical term for all fluid outside of the cells?
Extracellular fluid (ECF)
What is the primary determinant of if fluid will be intracellular or extracellular?
The quantity of sodium or potassium in the fluid.
What is an electrolyte?
They are molecules that contain positive or negative charges. Positive meaning there is one more positively charged proton than negatively charged electron, and negative being the opposite.
What is osmolality?
It is what regulates total body fluid and water allocation to all the compartments.
What determines how much water will remain extracellular or become intracellular?
Sodium levels in the body.
What are dipsogenic signals?
Signals such as high osmolality or low blood sugar that ignite sodium and water appetite. It is a key driver in thirst.
What happens when a person is hypovolemic?
Their blood pressure decreases due to a loss in total blood volume.
What are baroreceptors?
Nerves that detect pressure change in the heart or blood vessels. Detecting these changes stimulates thirst drive.
Does thirst drive match the amount of fluid loss during activity within the first few hours of activity?
No, so if a person is not conscious about fluid intake, then they make not be adequately replacing lost fluids.
What is a hypo-osmotic fluid?
A fluid with a lesser concentration of solutes.
What is one of the major adaptations of the body when being active in a warmer environment?
The body switches to a less-salty sweat.
Why does an active body switch to a more diluted sweat?
Fluid in an ICF space migrates to a ECF space so total volume does not decrease, which maintains blood pressure and limits the increase of plasma osmolality.
Why should people sweating during activity intake sodium with their fluids?
It helps in the retention of ingested fluids and naturally promotes fluid intake.
What happens when a considerable amount of fluid (but less than what was lost with sweat) is ingested after dehydration?
The majority of it remains as ECF. This decreases plasma osmolality-related thirst drive.
What is the gastric emptying rate (GER)?
The rate of which fluids and their contents pass through the stomach via the pyloric sphincter and into the small intestine.
What happens when GER is faster and more complete?
carbs and electrolytes are absorbed faster, where they feed the liver first and the rest of the body via the vascular system.
