Biology: Osmosis

about osmosis duhhhh

Fluid Mosaic Model

Description of what the cell membrane looks and functions like; the components of the model flow and change position

What are the components of the fluid mosaic model?

Phospholipids, cholesterol, proteins, carbohydrates

What is the purpose of phospholipids in the FMM?

diffuse rapidly and laterally in the membrane, make up the hydrophilic surface and hydrophobic inside of the membrane 

What is the purpose of Cholesterol in the FMM?

regulates fluidity of the membrane and changes based on the temperature of the cell’s environment

What is the purpose of protein in the FMM?

serve as channels or pumps to move materials in and out of cells, serve as enzymes, as structured attachments for the fibers of the cytoskeleton, or as part of the cell’s recognition sites

What is the purpose of carbohydrates in the FMM?

form specialized sites on the cell surface that allows cells to recognize each other

Plasma Membrane 

Separates cell from external environment, controls passage of organic molecules, ions, water, oxygen, and waste into and out of the cell

Phospholipid

major components of the plasma membrane, composed of a hydrophilic head and a hydrophobic tail

Phospholipid Bilayer 

makes up the cell membrane, the heads face out and the tails face each other 

Selectively Permeable

allows for certain materials to pass and not others

Diffusion

movement of molecules from a high area of concentration to an low area of concentration

Concentration Gradient

difference of concentration across space

Passive Transport

movement of substances from an area of high concentration to an area of low concentration without any energy (ATP) use 

Facilitated Diffusion

the diffusion of particles through the cell membrane with the help of transport proteins that cannot pass through the cell membrane alone

Osmosis

the movement of water molecules across the cell membrane from an area of high water concentration (low solute concentration) to an area of low water concentration (high solute concentration)

Isotonic 

water moves in and out of the cell in equal amounts 

Hypertonic

water moves out of the cell due to the lesser concentration of water in thee extracellular fluid

Hypotonic

water moves into the cell due to lower concentration of solutes in the extracellular fluid

Active Transport

movement of molecules or ions across a cell membrane from an area of low concentration to an area of high concentration, against their concentration gradient and with the use of energy (ATP)

Endocytosis

type of active transport that moves particles into a cell via vesicles

Exocytosis 

a process that expels material from the cell into the extracellular fluid via a vesicle; fuses with the cell membrane and is then let out