Term
|
Definition
|
|
Term
| what percent of an adult's body weight does water make up? |
|
Definition
|
|
Term
| lean tissue and adipose tissue |
|
Definition
lean tissue- 75% water
adipose tissue- 25% water |
|
|
Term
|
Definition
| fluid in the blood vessels and water found in tissues surrounding cells |
|
|
Term
|
Definition
|
|
Term
|
Definition
is a carrier of nutrients and waste, for example blood, the cytoplasm of the cell, and urinary excretion.
serves as a solvent, for example, for ionizing electrolytes and for molecules that are eligible for metabolic reactions.
participates in chemical or metabolic reactions as a substrate or a product.
lubricates joints and eyeball sockets.
is important in regulation of body temperature, both for cooling and heating.
maintains blood volume. |
|
|
Term
| adult water daily reccomendations |
|
Definition
| 1.0-1.5 mL/kcalorie, translates to two or three liters |
|
|
Term
|
Definition
| contribute to daily water intake |
|
|
Term
|
Definition
| intake must at least equal loss or there will be adverse complications |
|
|
Term
|
Definition
| on the order of 500 ml of urine per day and is essential for the excretion of waste |
|
|
Term
|
Definition
| excessive water loss due to sweating, vomiting, or diarrhea without adequate water intake |
|
|
Term
|
Definition
| thirst, fatigue, weakness, lack of appetite |
|
|
Term
| elderly people, active workers, and athletes are... |
|
Definition
| susceptible to dehydration |
|
|
Term
|
Definition
| the intake of over 10 liters of water over a short period of time, can lead to confusion, convulsions and even death, very rare |
|
|
Term
| electrolytes and other osmotic particles |
|
Definition
| are the major force in maintaining water compartments in the body and managing water balance |
|
|
Term
|
Definition
| potassium cations (K+) and phosphate anions (HPO4-2) |
|
|
Term
|
Definition
| sodium cations (Na+) and chloride anions (Cl-) |
|
|
Term
|
Definition
| moves Na+ and K+ across cell membranes as needed |
|
|
Term
| basics of the functioning nephron |
|
Definition
| filtration, reabsorption, excretion |
|
|
Term
| regulation of water and sodium balance |
|
Definition
Thirst, dry mouth, and dry mucus membranes are the first indicators of dehydration. As dehydration worsens blood pressure and blood volume drop, a rapid heartbeat develops, and general weakness occurs.
With a drop in blood volume, blood is concentrated with sodium, which signals the hypothalamus to stimulate the pituitary glands (in the brain) to release the hormone, anti-diuretic hormone (ADH).
ADH stimulates the kidneys to reabsorb more water from the nephron tubules back into the blood to dilute blood sodium concentration.
Dehydration can also reduce blood flow, that is, lower blood pressure. The kidney responds by releasing the enzyme renin into the blood, which activates the blood protein angiotensinogen converting it to angiotensin.
Angiotensin signals the adrenal glands to release the hormone, aldosterone. Aldosterone causes the kidney to reabsorb sodium (Na+). Na+ and other electrolytes attract water. When Na+ is retained or reabsorbed into blood, water follows via osmosis and blood volume and thus blood pressure is increased.
Angiotensin is also a powerful vasoconstrictor causing blood vessels to narrow which also increases blood pressure.
Overall, water is reabsorbed back into the body and blood pressure rises to prevent symptoms of dehydration. |
|
|
