Chapter 14 Part One - Water Flashcards
How long can you survive without water?
a few days
Water accounts for ___ to ___% of our body weight
50-75%
Intracellular
Found inside of the cell
- 2/3 of body water is this
Extracellular
Found outside of the cell
Interstital Fluid
extracellular fluid between cells
Intravascular Fluid
extracellular fluid in the blood and lymph
Solute
Substance dissolved in another substance (solvent), forming a solution.
Electrolytes
Compounds that separate into ions in water, making them able to conduct an electrical current.
- Type of solute
Ions
Atoms with an unequal number of protons and electrons
Concentration Gradient
Difference in the concentration of a solute from one area to another. Normally, a solute moves from where it is most concentrated to where it is least concentrated. When sodium is pumped outside the cell and potassium is pumped inside the cell, they are moving instead to where each is most concentrated- that is, against the concentration gradient.
Osmosis
Passive diffusion of water across a semipermeable membrane, ex: a cell membrane
Roles of Water
- maintenance of blood volume
- transport of nutrients and oxygen throughout the body
- basis for fluids synthesized in the body
- joint lubricant
- solvent in metabolic processes
- reactant in chemical reactions
- temperature regulation
- waste product removal
Specific Heat
Heat required to raise the temperature of one gram of any substance by one degree Celsius
Water has a (high or low) specific heat?
High → tends to resist large temperature fluctuations as a result
Typical daily urine output
1-2 L
Minimum daily urine output
600 mL
What is the greatest food source of water?
Beverages and Liquid Foods (Soup/Broth)
What are other sources of water?
Fruits and Vegetables;
Potatoes and Chicken/Steak
AI for Water
3.7 L for men, 2.7 L for women
How much water is produced from metabolism every day?
250-350 mL
Insensible Water Losses
Losses we don’t notice (sweat, respiration)
What two body parts are known for recycling water
kidneys and the intestines
Antidiuretic Hormone (ADH) (AKA Arginine Vasopressin)
Hormone secreted by the pituitary gland that signals the kidneys to decrease water excretion
Renin
Enzyme formed in the kidneys that is released in response to a low blood pressure.
Acts on the blood protein angiotensinogen I to angiotensinogen II.
Angiotensinogen II
Compound, produced from angiotensinogen I, that increases blood vessel constriction and triggers the production of the hormone aldosterone
Aldosterone
Hormone, produced in the adrenal glands, that acts on the kidneys, causing them to retain sodium and water
What can lead to dehydration?
- diarrhea
- vomiting
- fever
- heavy exercise
- hot weather
- dry environment
- high altitudes
Signs of Dehydration
- dry mouth and skin
- fatigue and muscle weakness
- decreased urine output
- deep yellow (concentrated) urine
- headaches
- dizziness
Hyponatremia
Low sodium levels in the blood
