Module 2 Flashcards
(24 cards)
What are the three anatomical compartments:
1) The Cranial cavity2) The thoracic cavity (pleural sac and pericardial sac)3) Abdominopelvic cavity (Abdominal cavity and Pelvic cavity)
What are the two Functional compartments:
1) The Extracellular fluid (Blood plasma and Interstitial fluid)2) Cells - Intracellular fluid (intracellular compartments)
What are the Four functions of a cell membrane?
1) Physical isolation: a physical barrier separating ICF and ECF as well as cell from environment2) Regulation of exchange with the environment: Controls entry, elimination and release3) Communication between the cell and its environment: contain proteins that allow for responding or interacting with the external environment4) Structural support: proteins in the membrane are used to make cell-to-cell connections (tissue) and to anchor the cytoskeleton
What is the cell membrane composed of? To be more metabolically active, the membrane must contain more of what component?
-Proteins, lipids, and small amounts of carbohydrates-The more protein a membrane has, the more metabolically active it is.
Label a general diagram of a lipid. How can they be arranged?
-Polar head (hydrophilic) and a non-polar fatty acid tail (hydrophobic) – amphipathic-Bilayers: sheet-Micelles: droplets of phospholipids-Liposomes have an aqueous center
What are the three types of lipids that can be found in the cell membrane?
Phospholipids, Sphingolipids, Cholesterol
Describe the fluid mosaic model
Proteins are dispersed throughout the membrane, and the extracellular surface contains glycoproteins and glycolipids
Distinguish between integral and peripheral proteins:
Integral:
-Transmembrane proteins-Lipid anchored proteins
-Roles: Membrane receptors, Cell adhesion molecules, transmembrane movement, Enzymes, mediators of intracellular signalling.
Peripheral:
-Attach to integral proteins or loosely attached to phospholipid heads-
Roles: Participate in intracellular signaling, form submembraneous cytoskeleton
What are the two types of lipid rafts and what is their importance?
Lipid rafts: Sphingolipid clusters with a high cholesterol content and high abundance of proteins.-Planar lipid raft: Flotillin-Caveolae: (Caveolin)
important in cell signal transduction
Describe the functions of a glycoproteins:
Serve as recognition sites for cell-to-cell interactions
How much of the body is water? Intracellular fluid, Plasma, Interstitial?
60% of the body is water. Total Body water: 2/3 ICF, 1/3 ECF (1/4 Plasma, 3/4 Interstitial Fluid)
Define osmotic equilibrium:
Fluid concentrations are equal; the amount of solute per volume of solution is equal.
Define osmosis
The movement of water across a membrane in response to a solute concentration gradient.
Describe the locations of solutes within the ICF and ECF.
Intracellular Fluid: High K+ and Proteins Interstitial fluid: High Na+ and Cl-Plasma: High Na+ Cl-, and Proteins
Define osmotic pressure.
The pressure that would have to be applied to oppose and prevent osmosis.
Define osmolarity
Is the overall solute concentration of a compartment, takes into account all solutes in the compartment, penetrating and non-penetrating. (relative/comparable term
Define isosmotic, hyperosmotic, and hypoosmotic
Isosmotic: equal Hyperosmotic: higher osmolarity Hyposmotic: lower osmolarity
Define tonicity
How a solution would affect cell volume if a cell were placed in the solution and allowed to come to equilibrium. Concerned with non-penetrating solutes only
Define Hypotonic, isotonic, hypertonic
Hypotonic: Burst/Swell (cell has low solute concentration)Isotonic: Equal concentrations Hypertonic: Shriveled (cell has low solute concentration)
Define diffusion:
The movement of molecules from an area of higher concentration to an area of lower concentration.
What are the general properties of diffusion?
1) Diffusion does not require and outside energy source
2) Diffuse from an area of high to low concentration
3) Diffusion continues until concentrations come to equilibrium
4) Diffusion is faster along higher concentration gradients, shorter distances, higher temperatures, for smaller molecules.
5) Can take place in an open system or across partition
Describe simple diffusion.
-For small uncharged molecules-Rate of diffusion is faster if the membranes surface area is larger, the membrane is thinner, the concentration gradient is larger, the membrane is more permeable to the molecule.-Membrane permeability depends on the molecules lipid solubility, size, and the lipid composition of the membrane.
Describe facilitated diffusion using channels and carriers.
-Move down concentration gradient
-No energy required-Stops once equilibrium is reached
Channel proteins:
-Mainly smaller substances
-Open channels: “leak channels”
-Gated channels: chemically gated (ligand), voltage gated, mechanically gated
Carrier proteins:
-Change conformation to move molecules
-Slower
-Small organic molecules that cannot pass through channels
