W5 - Mineral Water Fibre Alcohol Flashcards
List the roles of Water in the Body
●● Carries nutrients and waste products throughout the body
●● Maintains the structure of large molecules such as proteins and glycogen
●● Participates in metabolic reactions
●● Serves as the solvent for minerals, vitamins, amino acids, glucose, and many other small molecules so that they can participate in metabolic activities
●● Acts as a lubricant and cushion around joints and inside the eyes, the spinal cord, and, in pregnancy, the amniotic sac surrounding the fetus in the womb
●● Aids in the regulation of normal body temperature, as the evaporation of sweat from the skin removes excess heat from the body
●● Maintains blood volume
What do cells direct the movement of to control the movement of water?
Minerals
What are electrolyte solutions and how are they formed?
When a mineral salt dissolves in water it separates into ions. The ions are called electrolytes, and they help with the conduction of electricity. The solution that contains them are called electrolyte solutions
Do you have the same number of anions (-ve) and cations (+ve) in an electrolyte solution?
Yes. If a fluid contains 1,000 -ve charges it must also contain 1,000 +ve charges. However there can be different types of ions. If an anion enters a fluid, so must a cation, or another anion has to leave.Therefore whenever sodium (Na+) leaves a cell potassium ions (K+) enter. In fact whenever Na+ & K= ions are moving they’re generally going in opp directions
Which electrolytes reside primarily outside the cells and which within?
o/s sodium and chlorid i/s potassium, magnesium, phosphate and sulphate. Cell membranes are sleectively permeable meaning they allow the passage of some molecules but not others
What happens when an electrolyte moves across a cell membrane?
Water follows (towards the more concentrated solutes), whether the ion is +v or -ve - OSMOSIS. -ve ions follow +ve and water flows towards the more concentrated solution
What is osmotic pressure?
the amount of water needed to prevent the movement of water across a membrane
What is the role of proteins in the movement of ions in the cell membranes?
They help transport them, for example a protein that helps regulate the flow of ions and fluids in and out of the cells is the Na= K= pump.
How do the kidneys affects the movement of water?
They reabsorb needed substances and water and excrete in urine waster with some water
What hormones instruct the kidney to retain or release substances/ water?
ADH, renin, angiotensin and aldosterone
What is ADH and what does it do?
If blood volume or pressure falls too low, ADH stimulates the kidneys to reabsorb water and also triggers thirst
What does renin do?
If blood volume or pressure falls too low, kidneys release renin which triggers the release of aldosterone which causes the kidneys to reaborb soium and therefore water. It also hydolyses a protein from the liver caleld angiotensin to angiotensin I which can then be converted to angio II. Angio II is a powerful vasoconstrictor narrow the diameter of blood vessels and raising blood pressure
What does Aldosterone do and how is it realeased?
Angio II stimulates it’s release from the adrenal glands , signalling the kidneys to retain more sodium. So aldosterone does similar to renin, but renin also causes release … of angio II which as well as vaso stimulates release of aldoesterone\
The body uses ions to maintain fluid base and electrolyte balance. What else does it use them for?
Regulate acidity (pH) of it’s fluids (determined by concentration of Hydrogen (H-) ions)
What 3 systems defend the body against fluctuations in pH?
blood buffers, respiration in the lungs and excretion in the kidneys
How do blood buffers work?
bicarbonate (a base) and carbonic acid (an acid) act as buffers, substances that can neutralise acids or bases
How do the lungs helps maintain the pH balance?
If too much bicarbonate builds up respiration slows, CO2 is retained and forms more carbonic acid and vice versa
And the kidneys, how do they help maintain the pH balance?
By either reabsorbing or excreting bicarbonate
How much urine does the body ‘need’ to excrete per day to remove waste products?
500ml, if the person consume any more than this this is also excreted as urine