Basic Concepts Flashcards
True or false?
water is dipole
true
Describe how water has a partial positive and negative charge
oxygen (an electronegative atom) pulls the electrons from H, resulting in a partial positive charge
oxygen’s unpaired electrons result in a partial negative charge
the dipole characteristic of water allows ___ bonds to form
hydrogen
True or false?
Hydrogen bonding in water imparts its relatively low viscosity, surface tension, and boiling point
false; high
Hydrogen bonding between water and polar groups of bio-molecules allows water to be an excellent ___
solvent
Hydrogen bonding also occurs between various ___ groups of bio-molecules
polar
1 dl = ___ ml
100
50 g/L = ___ g/dl
5
Equivalent units are used for ions and are based on what?
available charges of the ion
For singly charged ions, one mole = ___ equivalent
one
For doubly charged ions, one mole = ___ equivalents
two ex: [Mg+2]
True or false?
pH can affect enzyme activity
true
Define osmolarity
the total number of solute particles in a solution
1M NaCL solution is ___ Osmolar
2
True or false?
Osmolality is the number of osmoles/kg solution
true
Osmotic pressure causes movement of H2O from ___ solution to ___ solution
dilute; concentration
True or false?
Cell membranes are impermeable to H2O
false; permeable
Define tonicity
relationship between two solutions separated by permeable membrane
Two solutions with equal osmolarities are considered ___
isotonic
A solution (A) with a greater osmolarity than another (B) is ___ with respect to B
hypertonic
H2O will move from a ___ solution to a ___ solution
hypotonic; hypertonic
What happens to cells bathed in a hypotonic solution?
they swell
hint: O in hypotonic looks like swollen cell
What happens to cells bathed in a hypertonic solution?
they shrink, as they become dehydrated
Hypertonic serum may also cause cellular dehydration which is thought to play a role in the CNS problems associated with what?
DKA
note: ions are too concentrated in the cell; the cells need water
A bronsted-lowry acid does what?
can donate an H+
A bronsted-lowry base does what?
can accept an H+
True or false?
strong acids only partially dissociate
false; completely dissociate
What is the normal blood pH range?
7.35-7.45
What does a large Ka mean in regards to dissociation
Larger Ka means more dissociation
Ka is a measure of the ___ of the weak acid
“strength”
A larger Ka is a ___ acid
stronger
A smaller Ka is a ___ acid
weaker
HA -> H+ A-
adding OH- will do what to this rxn?
decrease the [H+], driving net rxn to the right
Define a buffer system
a system that will resist large changes in pH from strong acids or bases
HA -> H+ A-
A- is the ____ ___ of HA
conjugate base
a buffer system has its best buffering capacity when pH = ?
pKa
At the greatest buffering capacity, relatively large amounts of base are required for relatively small changes in pH. true or false?
true
A buffering region on a titration curve, gives you a clue about the AA. Alanine has 2 buffering regions, therefore, has ___ titratable weak acid groups
2
CO2 + H2O -> H2CO3 -> HCO3- + H+
what enzyme reverses this reaction?
carbonic anhydrase
Bicarbonate is transported in the ___ to the ____
blood; lungs
CO2 + H2O -> H2CO3 -> HCO3- + H+
Carbon dioxide is expelled from the lungs, shifting the net reaction to the ___
left
What is the henderson hasselbach equation?
pH = pKa + log {A-}/{HA}
Keq = Ka = ?
[H+][A-}/[HA]
pH = ?
-log[H+]
DKA results in an excess of organic acids called ___ ___
ketone bodies
The “___” respirations are an attempt to decrease the [CO2] in the patient
kussmaul
