Phospholipid Bilayer
What is another name for the phospholipid bilayer in cells?
Cell membrane
What is the difference in the concentration gradient between active transport and passive transport?
Passive transport moves from a high concentration to a low concentration, while active trasnport moves from a low concentration to a high concentration.
In relation to the water gradient, how does water move in osmosis?
From areas of high water concentration to areas of low water concentration.
What is tonicity?
A solution's ability to cause a cell to gain or lose water.
What is energy?
The ability to promote change or do work
What is the permeability of the phospholipid bilayer?
Semipermeable
What is the goal of passive transport?
Solutes want to be equal concentration on both sides.
What does it mean that osmosis is permeability dependent?
Equilibrium wants the concentration to be the same on both sides, so if solutes can't pass the membrane due to permeability, water will move instead to help the cell reach equilibrium.
What does Hypo- Iso- and hyper- mean?
Hypo- below
Iso-same
Hyper-above
If I am holding a ball 5 feet above the ground, what type of energy does it have? Then I drop the ball. What type of energy does it have now?
When the ball is being held it has a high potential energy but when the ball is dropped that changes to a high kinetic energy.
What creates space in the phospholipid bilayer?
Unsaturated fatty acids
What does facilitated diffusion do?
Allows for the passage of molecules that are impermeable to the membrane to pass through the membrane via channel proteins.
What is an aquaporin?
A channel that allows for the passage of water through the plasma membrane.
If I put an animal cell into a hypertonic solution, what will happen to the cell?
The cell will shrivel.
What are two examples of potential energy and kinetic energy?
potential: chemical and gradients
kinetic: movement, thermal energy, light
The rate of diffusion across the bilayer depends on....
size, polarity, and charge
How does the transport protein allow solutes to pass through in active transport?
The protein changes shape to allow specific molecules through.
How does water move in relation to solute concentration?
If I put a plant cell into a hypotonic solution, what will happen to the cell?
The cell membrane will swell creating pressure on the cell wall, which is normal for plant cells. This is called turgid.
What is the 1st law of thermodynamics?
Energy cannot be created or destroyed.
Why is the phospholipid bilayer a bilayer?
The tails are hydrophobic and do not want to touch water, and the heads are hydrophilic and like water, so they align so that each piece is satisfied.
What is the difference between endocytosis and exocytosis?
Exocytosis is the merging of a vesicle with the plasma membrane to export substances. Endocytosis is the inward pinching off of a vacuole or vesicle for import into the cell.
How do you calculate concentration?
solute/solvent
If I place an animal cell that has 10g of salt in its cytoplasm into a solution that has 5g of salt, what will happen to the cell?
The cell will swell because it has a higher concentration of solute, which will cause water to flow in.
What is the 2nd law of thermodynamics?
Energy conversion increases entropy, and heat will always be emitted.