Fluid Homeostasis and Blood Flashcards
Blood is comprised of % plasma and % cells?
55% plasma
45% cells
Serum is defined as?
Plasma, minus the clotting factors
Packed cell volume is also known as…? What is the value approximately?
Haematocrit, and 0.45
What is the most abundant white cell?
Neutrophil
What is the second most abundant white cell?
Lymphocyte
What is the intracellular and extracellular concentrations of Na+?
Intracellular = 10mM Extracellular = 142 mM
What is the intracellular and extracellular concentrations of K+?
Intracellular = 160 mM Extracellular = 4 mM
What is the intracellular and extracellular concentrations of Ca2+?
Intracellular = 0.1 uM Extracellular = 2.5 mM
Define Osmolarity / Osmolality
Concentration of solute particles in solution
What are the units for Osmolarity / Osmolality?
mOsm / kg
mOsm / l
Define osmosis
Movement of water down its concentration gradient from low osmolarity (less concentrated solution) to high osmolarity (more concentrated solution) across a semi permeable membrane
Define tonicity.
What are the names given to the extreme tonic states and what affects do they have on a cell?
The strength of solution as it affects cell volume
Hypertonic, will cause crenation
Hypotonic, will cause lysis
What is the functional unit of a kidney called?
Nephron
Describe the sequence of whereby blood fllters as it passes through the Nephron of kidneys
Proximal tubule (solutes resorbed) –> Loop of Henle (electrolytes resorbed) –> Distal tubule (ion regulation) –> Collecting duct (water resorbed)
Blood vessels are lined with endothelium - what is the histology of endothelium?
Simple squamous epithelium
What occurs in odema?
Movement of fluid in and out of interstitial fluid spaces is not in equilibrium, whereby hydrostatic forces > osmotic forces = leading to fluid build up in tissues
What are the two Starling forces?
Hydrostatic and Osmotic forces
If hydrostatic force > osmotic force at the arterial end - what happens?
Pushes fluid out of vessels into tissues (oedema)
If osmotic force > hydrostatic force at the venous end - what happens?
This pushes fluid into vessels from tissue (hypervolemia)
How is elephantiasis caused?
Blockage of lymph nodes due to a parasitic infection
