Diffusion and Osmosis
Main Jobs of the cell membrane
Isolate the cytoplasm from the external environment Regulate the exchange of substances Communicate with other cells Mark" the cell with proteins that identify it
What is osmosis?
The diffusion of water molecules through a semipermeable membrane.
Hypertonic
used to compare two solutions. The solution with the higher solute concentration is hypertonic to the other solution.
What type of membrane do cells have?
A Semi Permeable membrane.
What does the cell membrane do
Allows certain things through
Blood cell with Hypotonic solution
Burst
What are two processes that help maintain homeostasis in a cell?
Diffusion and Osmosis
What happens when there is a high concentration of water inside the human cell? in the plant cell?
Human cell-Water leaves and causes it to shrink. Then a plant cell wilt.
What is a semipermeable membrane
It allows certain things through and blocks out the others.
What role does the concentration gradient play in diffusion?
It determines the direction molecules will move.
Are the Hydrophobic heads water loving
No
Is energy involved in moving molecules down a concentration gradient
No
Is energy needed for passive transport?
No
True Or False Is a gradient an actual Slope
No
Blood Cell with Isotonic solution
Normal
Plant cell with Isotonic solution
Normal
Isotonic
Referring to two solutions when the concentrations of solutes are the same. For example when water moves out water moves in to take its place.
Blood Cell with Hypertonic solution
Shrink
Plant cell with Hypotonic solution
Swells
What is a concentration gradient
The gradual difference in the concentration of solutes in a solution in two areas.
What is homeostasis?
The internal environment of the cell stays the same. Or balanced
What is active transport?
The movement of molecules from a low concentration to a high concentration. Molecules are moving up the concentration gradient.
What is Diffusion
The movement of molecules from high concentration to an area of lower concentration. No energy.
Why are diffusion and osmosis important to cell function?
They allow other water and substances to enter and leave a cell. This movement provides a way for cells to maintain an internal balance.
How do these molecules move during osmosis?
They move from where they are more water molecules to where there are very few.
Molecules will move across a semipermeable membrane until they are?
Until they are balanced.
Hydrophobic
Water fearing repels any molecule with a charge
What is Hydrophilic
Water loving
What molecules move during osmosis?
Water molecules move during osmosis.
What happens in the plant cell when there is equal concentration of water inside and outside of the cell?
Water molecules move in and out at the same time.
What happens to red blood cells when there is more water outside of the cells?
Water moves into the cell and it swells. It may break.
What happens to red blood cells when there is less water outside of the cells?
Water moves out of the cell and it shrinks.
What is passive transport?
When molecules move down a concentration gradient and no energy is used.
How do molecules move during diffusion?
When molecules move from a high area of concentration to a low area of concentration.
Is Diffusion a type of passive transport?
Yes
Is the hydrophilic head in the phospholipid bilayer
Yes
Does Active Transport Require Energy?
Yes and it requires carrier molecules ( protein embedded in the membrane)
Solution
group of molecules that are mixed and evenly distributed. Ex. Salt water
Solvent
substance that dissolves another substance in a solution. For example, in salt water, salt is the solvent.
What is Osmosis
the diffusion of water through a thin membrane semi-permeable (selectively permeable)- decides what comes through
Solute
the substance that is dissolved in the solvent in a solution. For example, in salt water, salt is the solute.
Hypotonic
used to compare two solutions the solution with the lower solute concentration is hypotonic to the other solution.
Plant cell with Hypertonic solution
wilts
