Terminology
The maintenance of equilibrium around a point or value
Homeostasis
A type of transport that does not require energy to move substances across membranes
Passive transport
Moves molecules across a membrane from low concentration to high concentration
Active transport
Tonicity
The name of the plasma membrane model
Fluid Mosaic Model
A change in the internal or external environment
Stimulus
Passive transport moves substances _____ the concentration gradient
down
Active transport moves molecules _____ the concentration gradient
Up
A solution is _____ to a cell if it has the same concentration of dissolved particles as the cell
Isotonic
Composed of two fatty acid chains attached to a glycerol backbone and a phosphate group
Phospholipids
Attracted to water
Hydrophilic
The movement of water across a semipermeable membrane down the concentration gradient
Osmosis
The gradient of both charge and concentration
True or False: If a solution is isotonic to a cell, that means that nothing is moving in or out of the cell
False! Molecules move in the cell at the same rate that they move out of the cell
What are the two types of proteins present in the plasma membrane?
Integral proteins and peripheral proteins
Materials move across the plasma membrane with the assistance of transport proteins
Facilitated diffusion
Which type of molecules moves more easily through the plasma membrane? (hydrophobic or hydrophilic)
Hydrophilic
This type of active transport uses ATP to alter the shape of the channel protein.
Sodium Potassium Pump
A ___ solution has a higher concentration of dissolved particles than a cell
Hypertonic
Name for a protein with a carbohydrate attached
Glycoprotein
Expels materials from the cell out into the extracellular fluid
Exocytosis
What is selective permeability?
Allows some but not all substances to cross
A type of active transport that moves particles into a cell by forming a pocket around the target particle
Endocytosis
A ____ solution has a lower concentration of dissolved particles than a cell
Hypotonic
Name for a lipid with a carbohydrate attached
Glycolipid