Chapter 2 - Cell Physiology Flashcards
Passive forces
- forces that do not require the cell to expend energy to produce movement
Selectively permeable
- characteristic of the plasma membrane - permits some particles to pass through, while excluding others
Active forces
- forces that do require the cell to expend energy (ATP) to transport a substance across the membrane
Diffusion
-
Concentration gradient
- a difference in concentration between two adjacent areas
Net diffusion
- the difference between two opposing movements
Steady state
- movement of molecules from area A to area B that is exactly matched by the movement of molecules from area B to area A
Fick’s law of diffusion
- factors contributing to the rate of net diffusion across the membrane
Electrical gradient
- a difference in charge between two adjacent areas that promotes the movement of ions towards the area of opposite charge
Electrochemical gradient
- when both an electrical and a concentration gradient act simultaneously on a specific ion
Aquaporins
- channels used for the passage of water - formed by membrane proteins - allow about a billion water molecules can pass single file through this channel in one second
Osmosis
- net movement of water across a membrane down its concentration gradient - passive
Hydrostatic pressure
- the pressure exerted by a stationary fluid on an object (the plasma membrane)
Osmotic pressure
- a measure of the tendency for water to move into that solution because of its relative concentration of nonpenetrating solute sand water
Tonicity
- the effect the solution has on cell volume when the solution surrounds the cell
Isotonic solution
- a solution with the same concentration of nonpenetrating solutes as normal body cells do
Hypotonic solution
- a dilute solution - a solution with a below normal concentration of nonpenetrating solutes - causes RBCs to swell
Hypertonic solution
- a concentrated solution - a solution w an above normal concentration of nonpenetrating solutes - the cells shrink as they lose water by osmosis
Transport maximum
- the limit to the amount of a substance a carrier can transport across the membrane in a give time - related to carrier-mediated transport
Carrier-mediated transport
- a molecule to be transported attaches to a binding site within the interior of the carrier on one side of the membrane - binding causes the carrier to flip its shape so that the same site is now exposed to the other side of the membrane - the bound molecule detaches from the carrier - the carrier reverts to its original shape
Active transport
- requires the carrier to expend energy to transfer its passenger uphill against a concentration gradient, from an area of lower concentration to an area of higher concentration - used to transport specific ions or polar molecule
Hydrogen ion H+ pumps
- an example of the simple active transport - used by specialized stomach cells to transport H+ into the stomach lumen in association w he secretion of HCl during digestion of a meal - moves H+ against a tremendous gradient
Na+/K+ ATPase pump
- involves the transfer of three sodium ions out of the cell and two potassium ions in - an example of active transport
Cotransport carriers
- an example of secondary active transport - example: luminal carriers in intestinal and kidney cells - two binding sites, one for Na+ and one for the nutrient molecule
Secondary active transport
- Active transport - moves molecules against the concentration gradient - driven by ion gradient established by ATP requiring primary pump
Ion concentration gradient
-
Vesicular transport
- transfers large particles between the ECF and the ICF by wrapping contents in membrane enclosed vesicles - requires energy expenditures by the cell - active method of transport
Pinocytosis
- brings a small droplet of ECF into the cell - form of active, vesicular transport - plasma membrane dips inwards and pinches off at surface, forming an internalized vesicle
Receptor mediated endocytosis
- used to transport specific large polar molecule - active, vesicular transport - plasma membrane dips inwards and pinches off at the surface, forming an internalized vesicle
Phagocytosis
- used to transport multimolecular particles (bacteria and cellular debris) - active form of vesicular transport - cell extends pseudopods that surround particle, forming an internalized vesicle
Exocytosis
- used to transport secretory products and large molecules passing through the cell intact - active, vesicular transport
Nucleus
- DNA and specialized proteins enclosed by a double-layered membrane - acts as a control centre of the cell providing storage of genetic material
Cytoplasm
- the portion of the cell’s interior not occupied by the nucleus but contains numerous organelles, structural proteins, transport and secretory vesicles, and enzymes
Intermediary metabolism
- refers collectively to the large set of chemical reactions inside the cell that involve the degradation, synthesis, and transformation of small organic molecules.
Anabolic
- processes that favour the synthesis of molecules for building up organs and tissues
Catabolic
- processes that favour the breakdown of complex molecules into more simpler ones
Adenosine triphosphate (ATP)
- consists of adenosine with three phosphate groups attached - the universal energy carrier - cells use ATP to pay for the cost of operating he body’s cells
Adenosine diphosphate
- adenosine with two phosphate groups attached plus inorganic phosphate and energy -
Reverse
- characteristic of the plasma membrane - permits some particles to pass through, while excluding others
Selectively permeable
Reverse
- forces that do not require the cell to expend energy to produce movement
Passive forces
Reverse
- forces that do require the cell to expend energy (ATP) to transport a substance across the membrane
Active forces
Reverse
-
Diffusion
Reverse
- a difference in concentration between two adjacent areas
Concentration gradient
Reverse
- the difference between two opposing movements
Net diffusion
Reverse
- movement of molecules from area A to area B that is exactly matched by the movement of molecules from area B to area A
Steady state
Reverse
- factors contributing to the rate of net diffusion across the membrane
Fick’s law of diffusion
Reverse
- a difference in charge between two adjacent areas that promotes the movement of ions towards the area of opposite charge
Electrical gradient
Reverse
- when both an electrical and a concentration gradient act simultaneously on a specific ion
Electrochemical gradient
Reverse
- channels used for the passage of water - formed by membrane proteins - allow about a billion water molecules can pass single file through this channel in one second
Aquaporins
Reverse
- net movement of water across a membrane down its concentration gradient - passive
Osmosis
Reverse
- the pressure exerted by a stationary fluid on an object (the plasma membrane)
Hydrostatic pressure
Reverse
- a measure of the tendency for water to move into that solution because of its relative concentration of nonpenetrating solute sand water
Osmotic pressure
Reverse
- the effect the solution has on cell volume when the solution surrounds the cell
Tonicity
Reverse
- a solution with the same concentration of nonpenetrating solutes as normal body cells do
Isotonic solution
Reverse
- a dilute solution - a solution with a below normal concentration of nonpenetrating solutes - causes RBCs to swell
Hypotonic solution
Reverse
- a concentrated solution - a solution w an above normal concentration of nonpenetrating solutes - the cells shrink as they lose water by osmosis
Hypertonic solution
Reverse
- the limit to the amount of a substance a carrier can transport across the membrane in a give time - related to carrier-mediated transport
Transport maximum
Reverse
- a molecule to be transported attaches to a binding site within the interior of the carrier on one side of the membrane - binding causes the carrier to flip its shape so that the same site is now exposed to the other side of the membrane - the bound molecule detaches from the carrier - the carrier reverts to its original shape
Carrier-mediated transport
Reverse
- requires the carrier to expend energy to transfer its passenger uphill against a concentration gradient, from an area of lower concentration to an area of higher concentration - used to transport specific ions or polar molecule
Active transport
Reverse
- an example of the simple active transport - used by specialized stomach cells to transport H+ into the stomach lumen in association w he secretion of HCl during digestion of a meal - moves H+ against a tremendous gradient
Hydrogen ion H+ pumps
Reverse
- involves the transfer of three sodium ions out of the cell and two potassium ions in - an example of active transport
Na+/K+ ATPase pump
Reverse
- an example of secondary active transport - example: luminal carriers in intestinal and kidney cells - two binding sites, one for Na+ and one for the nutrient molecule
Cotransport carriers
Reverse
- Active transport - moves molecules against the concentration gradient - driven by ion gradient established by ATP requiring primary pump
Secondary active transport
Reverse
-
Ion concentration gradient
Reverse
- transfers large particles between the ECF and the ICF by wrapping contents in membrane enclosed vesicles - requires energy expenditures by the cell - active method of transport
Vesicular transport
Reverse
- brings a small droplet of ECF into the cell - form of active, vesicular transport - plasma membrane dips inwards and pinches off at surface, forming an internalized vesicle
Pinocytosis
Reverse
- used to transport specific large polar molecule - active, vesicular transport - plasma membrane dips inwards and pinches off at the surface, forming an internalized vesicle
Receptor mediated endocytosis
Reverse
- used to transport multimolecular particles (bacteria and cellular debris) - active form of vesicular transport - cell extends pseudopods that surround particle, forming an internalized vesicle
Phagocytosis
Reverse
- used to transport secretory products and large molecules passing through the cell intact - active, vesicular transport
Exocytosis
Reverse
- DNA and specialized proteins enclosed by a double-layered membrane - acts as a control centre of the cell providing storage of genetic material
Nucleus
Reverse
- the portion of the cell’s interior not occupied by the nucleus but contains numerous organelles, structural proteins, transport and secretory vesicles, and enzymes
Cytoplasm
Reverse
- refers collectively to the large set of chemical reactions inside the cell that involve the degradation, synthesis, and transformation of small organic molecules.
Intermediary metabolism
Reverse
- processes that favour the synthesis of molecules for building up organs and tissues
Anabolic
Reverse
- processes that favour the breakdown of complex molecules into more simpler ones
Catabolic
Reverse
- consists of adenosine with three phosphate groups attached - the universal energy carrier - cells use ATP to pay for the cost of operating he body’s cells
Adenosine triphosphate (ATP)
Reverse
- adenosine with two phosphate groups attached plus inorganic phosphate and energy -
Adenosine diphosphate