Week 11 Flashcards
is there more water in the extracellular fluid or the intracellular fluid
intracellular fluid
2/3 of the body’s water
Do obese or lean people have more water per % body weight
Lean bodies have more water as % of body weight than obese individuals
how does the sodium-potassium pump help keep the water balanced in the body?
its moves ions against their concentration gradients by active transport. water moves into the area of greater concentration of Na+
where is there a greater concentration of K and Na+ ions, inside the cell or outside the cell
Higher concentration of Na+ outside the cell
Higher concentration of K inside the cell
If 3 Na+ ions are actively transported across the membrane into the cell how many K+ ions move out of the cell?
2
Define electrolytes
elements that separate into ions in water make the water able to conduct electrical current.
what are 5 functions of water in the body?
- helps maintain blood volume
- solvents for many reactions
- precursor for body fluids
- temperature regulation
- waste product removal
What is the AI for water?
15 cups for men
11 cups for women
what is the water AI based off?
80% from fluid intake, 20% from food
intake
what happens when there water deficiency? how does the body react?
dehydrations
body reacts by
- release of anti diuretic hormone
- renin-antiogension system
- aldosterone pathway
What happens in water toxicity?
Concentration of electrolytes is diluted, especially sodium = hyponatremia
Water from diluted blood is pulled into cells by osmosis
Diluted blood and swollen cells can cause headache, blurred vision, muscle cramps
What is hyponatremia?
Low sodium levels in blood
what is the functional unit of the kidneys?
the Nephron
what are the different parts of the nephron?
afferent arteriol glomerular capilaries bowmans capsule efferent arteriol Proximal convoluted tubule Distal convoluted tubule Collecting duct loop of henle
when and where is renin secreted?
secreted by the kidneys when sodium or blood volume is decreases (low blood pressure)
what is the function of renin?
converts angioteniogen to angiotensin 1
where is angioteniogen produced?
liver
how is angiotensin 1 (inactive) converted to angiotensin 2 (active form)?
by angiotensin converting enzyme (ACE)
what is the functionof angiotensin 2?
restriction of small blood vessels leading to a increased BP
promotes relsease of aldosterone
What is the function of aldosterone?
stimulates Na+ reabsorption increasing the ECF osmorality and thus fulid retention as water follows Na+
Anti-diuretic hormone (ADH) also known as vassiopressin is secreted from where?
posterior pituritary gland
When is ADH released?
when blood pressure is low
What is the function of ADH?
increases water permeablility and thus promotes water reabsorption, reducing urine output and increasing the blood pressure
when and where are Atrial natriuretic factor (ANF) released?
release by atrial myoctyes (heart) in response to raised blood pressure
what is the function of atrial natriuretic factor (ANF)?
to reduce sodium and water retention in the body by promoting sodium secretion. Thus reducing the blood volume and decreasing blood pressure.
what does alcohol consumption do to water balance in the body?
inhibits the action of ADH and thus causing dehydration
what is the difference between major minerals and trace (minor) minerals?
need:
>100mg per day = major minerals
<100mg per day = trace (minor) minerals
Which of the follow are major minerals and minor (trace) minerals?
calcium, iron, magnesium, zinc, chloride, sodium, sulfur, seleium, chromium, potassium, molybdem, flurine, iodine, copper, manganese, phosphorus
major
calcium, phospherus, potassium, sulfur, sodium, chloride, magnesium
Minor
iron, manganese, copper, iodine, flurine, molybdem, chromium, seleium, zinc
what factors impair the bioavailablity of minerals?
excess fibre oxlic acid polyphenols and tannis (phytochemicals) high doses of minerals antacids: because of reduced stomach acidity
how does excess fibre affect bioavailablity of minerals?
Phytic acid found in fibre (phytate in legumes and whole grains): binds to minerals & leads to excretion. decrease bioavailability
Leavened breads with yeast may break the bonds between the phytates and the minerals: ↑ bioavailability of minerals
how does oxlic acid decrease bioavailablity of minerals?
oxlic acid in dark green leafy vegetables: binds minerals and makes them less bioavailable