Term
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Definition
| Membrane permeability x Surface Area x Concentration gradient |
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Term
| Fluid composition in body |
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Definition
2/3 intracellular
1/3 extracellular
(Within extracellular, 75% interstitial fluid, 25% plasma)
- Plasma has more protein than interstitial fluid |
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Term
| Is blood considered connective tissue? |
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Definition
| Yes, blood is considered connective tissue because blood connects various body organs/tissues and blood cells have same embryonic origin as other connective tissue. |
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Term
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Definition
Concentration of solute particles (penetrating and non-penetrating)
- High osmolarity = high solute concentration = low water concentration |
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Term
| Concentration of pure water |
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Definition
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Term
| Relationship between Osmolarity and molarity |
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Definition
For non-dissociable solutes: Osmolarity = molarity
For dissociable solutes: osmolarity = molarity x number of particles/molecule |
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Term
| Does volume change with a membrane permeable to both solute and water? |
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Definition
| No, water movement accompanied by solute movement so no volume change. |
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Term
| Does volume change with membrane permeable to water only? |
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Definition
| Yes, because movement of water alone balances osmolarity. High osmolarity region expands volume compared to low osmolarity region because water flows towards high osmolarity. |
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Term
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Definition
Indicates a solution's effect on cell volume. Depends on non-penetrating solutes only.
- Hypertonic if cell shrinks (water flows out of cell)
- Hypotonic if cell swells (water flows into cell)
- Isotonic if no cell volume change |
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Term
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Definition
| Pressure caused by water flow from pure water to solute-containing solution. Water flows from lower osmotic pressure to higher pressure because higher pressure solution indicates more solute concentration. |
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Term
| Formula for Osmotic Pressure (pi symbol) |
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Definition
R x T x Osmotic coefficient (which looks like green lantern) x Osmolarity
R = gas constant
T = absolute temperature |
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Term
| Name 3 types of ion channels |
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Definition
1) Ligand-gated (neurotransmitters)
2) Voltage-gated (electrical)
3) Stretch-activated (mechanoreceptors, cytoskeletal network) |
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Term
| Name 3 mechanisms of diffusion |
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Definition
1) Diffusion across lipid bilayer
2) Osmosis of water
3) Diffusion through protein pores (ion channels) |
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Term
| Name 3 types of carrier-mediated transport |
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Definition
1) Facilitated diffusion
2) Active transport
3) Coupled Carrier transport |
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Term
| What is the mechanistic model of facilitated diffusion? |
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Definition
| 1) Molecule binds to transporter on one side of membrane. 2) Binding causes conformational change of transporter and exposes molecule to other side. |
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Term
| Primary active transport vs Secondary active transport |
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Definition
Primary: direct use of ATP
- Ex: Na/K ATPase pump (Na out, K in against concentration gradients)
Secondary: use of electrochemical gradient across a membrane
- Ex: coupled carrier transport |
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Term
| Facilitated diffusion example of insulin and glucose |
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Definition
Intracellular glucose concentration lower than extracellular b/c glucose is immediately metabolized. Constant net influx of glucose.
Insulin increases number of glucose transporters, therefore increasing glucose movement into cells. When insulin is not available (type I diabetes), glucose accumulates in extracellular fluid. |
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Term
| Define coupled carrier transport and its two types |
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Definition
When concentration gradient of one ion (electrical gradient) is used to drive transport of another solute against its concentration gradient.
1) Co-transport = same direction.
- Ex: Na and glucose
2) Counter-transport = opposite directions/exchange.
- Ex: Na and Ca exchange for cardiac muscle contraction |
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Term
| Regulation of Ca in cardiac muscle contraction |
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Definition
Na/Ca exchange
Both Ca influx and release from SR are important for activating cardiac muscle contraction. |
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Term
| Summary of transport mechanisms |
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Definition
Ion channels: Na, K, Cl, Ca
Facilitated diffusion: Glucose
Secondary active transport:
Cl and HCO3, Na and Ca, Na and H, Na and amino acids
Primary active transport: H pump outwards, Na/K pump, Ca pump outwards (SR) |
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Term
| 2 examples of epithelial transport |
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Definition
1) Na flows into epithelial cell through ion channel from intestinal lumen, Na/K ATP pump pumps Na into capillary.
2) Na/glucose cotransport from intestinal lumen into epithelial cell, then facilitated diffusion of glucose and Na/K ATP pump pumps Na into capillary |
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Term
| Relationship between water and Na across intestinal epithelium |
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Definition
| Diffusion of water follows Na transport across intestinal epithelium. Na ion channel from lumen to epithelial cell, ATP pump to pump Na into capillary |
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