Physiology Flashcards Preview

DENT 291 > Physiology > Flashcards

Flashcards in Physiology Deck (16):

Describe BRCA 1

protein which aids in dsDNA break repair; acts as a tumor suppressor--a mutation in it may cause lack of repressor function and can cause breast cancer


describe CFTR

protein which pumps CL and bicarb; important for movement of water--mutation in BOTH alleles can lead to thickened mucous, resp infections, pancreas--malnutrition and diabetes


describe FAD

familial early onset alzheimer's disease (30-60 years of age); single-gene mutation can cause it-->amyloid precursor protein (presenilin 1 or 2)


what is LOAD?

late onset alz disease, after 60yrs; combination of factors contributes to the onset, progression and severity; genetics is a 60-80% risk factor; APOE is a risk factor-->involved in the synth of apolipoprotein E,, which is a cholesterol carrier to the brain; there are several alleles, one of which is protective; APOE e4 is present in 40% of all LOAD cases, is the risk factor allele.


what do unicellular organisms requir?

Information store (DNA/RNA)
Energy & substrate uptake
Excretion mechanism
--Makes energy extraction more efficient, but not required
Defense mechs
Growth & repair mechs
Volume (solute) control
Temperature control?
Border between internal and external environment


equation for mass balance?

Total amount (or load) of Substance X
= intake + production – excretion – metabolism


what are the body's options for output?

excretion--lungs, urine, feces, etc
metabolism-->metabolize to a different substance


what is clearance?

the rate at which a substance disappears from the body


mass flow definition and equation

Defined as the rate of intake, production or output of x
Mass flow = concentration x volume flow
amount/min = amount/vol x vol/min


how is body temp regulated?

hypothalamus is the control centre for body temp--it's at 37.1 C; if the body deviates from this, hypothal activates corrective mechs


Output methods for fluids?

kidneys, lungs, feces, sweat, skin


what is transcellular fluid, and give examples?

Specialized type of extracellular fluid counting for another 1 – 2 liters. The composition of this fluid differs and can be completely different from the main compartments.
Synovial space
Peritoneal space
-Digestive system cavity
Pericardial space
-CV system
Intraocular space
Cerebrospinal fluid


total body water in L, and the % or L of the fluid compartments?

60L in total; 40L is ICF; 12L is interstitial fluid; 3L is plasma


ECF composition?

The most important difference between plasma and interstitial fluid is the higher concentration of proteins in the plasma
ECF contains large amount of sodium and chloride
Reasonably high bicarbonate
But only small amounts of potassium, calcium, magnesium and phosphate
All carefully regulated mainly by the kidney


what molecules can pass through the lipid membrane without carriers?

O2, CO2, and other small, nonpolar molecues; some H2O molecules


what molecules can't pass through the lipid membrane without carriers?

glucose and other large polar, water sol molecules; ions (e.g. Na2+, Ca2+, K+, etc) most water molecules