Garafalo Review Flashcards
Ionic composition - ecf / icf
Sodium- e- 135-147mEq/L
i - 10-15
Potassium - e - 3.5-5.0
i - 120-150
Chloride - e - 95-105
i - 20-30
Bicarbonate - e - 22-28
i - 12-16
Calcium - e- 2.1-2.8
i - 0.0000007
Component makeup of a cell membrane.
- Phospholipids (70%)
- Cholesterol (20%)
- Glycolipids (5%)
Six major functions of cell membrane
- Transport
- Enzymatic Regulation
- Signal transduction
- Cell-Cell recognition
- Intercellular joining
- Attachment to cytoskeleton and extracellular matrix.
Cytoskeleton components
(Provides cell structure)
- Microtubules
- Microfilaments
- Intermediate filaments
Substances permeable to the cell membrane
- Gases ( O2 and CO2)
- Non-polar hydrophobic molecules (benzene)
- Small polar molecules (water, ethanol)
Substances not permeable to the cell membrane
- Large polar molecules (Glucose)
- Amino acids
- Charged molecules ( H+, Cl-, Na+, Ca2+)
Most abundant body lipid
Phospholipid
Cytosol functions
- Enzymatic regulation
- “intermediary” metabolism
Protein’s critical role in membrane function
- Structural support
- Recognition
- Communication
- Transport
Membrane permeability factors
- Lipid solubility
- Size
- Charge
- Presence of channels and transporters
Membrane fluidity factors
- Membranes molecules held in place by relatively weak hydrophobic interactions.
- Most lipids and some proteins drift laterally.
- Influenced by temperature.
- Membranes rich in unsaturated (compared to saturated fatty acids) fatty acids are more fluid because of the the double bond kink in its structure that doesn’t allow tight packing.
Cell identity markers on membranes
carbohydrate groups join with lipids to form glycolipids and with proteins to form glycoproteins.
Resting membrane potential factors
- Presence of fixed non-diffusible anions inside the cell.
- Preferential permeability of the PM
- The sodium-potassium pump
Neuron location where ligand-gated channels are prevalent
Dendrites and Soma
Increase in Ach effect on the membrane potential
opens more depolarization