Physiological Fluids Flashcards
What are physiological fluids ?
Are the fluids essential to the function of the cell.
The bodily fluids are weak solution of salts in water
They consist of intracellular fluid and the extra-cellular fluids
What’s the definition of a molar solution ?
Is the molecular weight of a substance in grammes, dissolved in one litre of water
What’s the definition of a millimolar solution ?
Is the molecular weight of a substance in grammes, dissolved in one litre of water
Explain why specialised systems had to be brought about for existence on land for ingestion and excretion ?
Ingestion and excretion cannot be by direct contact with an aqueous solution and thus specialised systems had to evolve to cope with this major change of environment
What do the specialised systems have to involve to develop an internal sea ?
Involve a waterproof covering, a means of water intake and excretion, fluid circulation and a monitoring system for osmotic pressure and volume
What 2 fluids produce physiological fluids ?
1- The extracellular fluids including blood plasma and
2- Intracellular fluids
What is extracellular and intracellular fluids in terms of dissolved ions ?
1- In terms of dissolved ions extracellular fluids, are weak solution of common salt in water
2- Intracellular fluids in terms of dissolved ions, are weak solutions of potassium chloride in water
Explain how solutes dissolved in water in specific concentrations define physiological fluids ?
They are in very low concentrations yet have profound effects upon animals cells
What percentage of vertebrates are water ?
Vertebrates have approx 60 percent of their body weight as water.
What percentage of water in the body is within cells and what percentage is outside of cells ?
Most of the water in the body is within cells ( 67%)
Of the remainder outside the cells most is interstitial fluid ( 26%)
What is the extracellular fluid a large solution of ?
Sodium chloride
How do the cation k+ and the anion cl- move freely across the membrane ?
The cell membrane is a semi permeable membrane and water movement between the compartment are entirely due to osmosis.
How does water end up being transported around the body ?
Water enters the body via the gut
Fluid is transferred from the gut to the plasma and thereby transported around the body
What is total water in the body regulated by ?
by thirst and antidiuretic hormone
Why are intracellular and extracellular fluids solute composition very different ?
As they are separated by semi-permeable membranes
