Cell Membrane Worksheet
List 4 functions of the cell or plasma membrane:
1. Selective Permeability 2. Cell Recognition 3. Cell Junctions 4. Cell Identification
This pump uses ___ to move ions ___ the concentration gradient.
ATP against
The cell membrane is made of a phospholipid ____
Bilayer
Another type of lipid in the cell membrane is ____ that makes the membrane more fluid.
Cholesterol
Define Osmosis
Diffusion of water across a membrane from a region of high water concentration to a region of low water concentration.
Diffusion does not require ____ and the water or molecules are moving ___ through the concentration gradient.
Energy Down
Define Isotonic
Equal concentration of solute on each side of the membrane.
Define Hypertonic
Greater solute concentration outside of the cell.
cholesterol's function
Helps maintain flexibility of membrane
Phospholipids can move ___ and allow water and other ___ molecules to pass through into or out of the cell.
Laterally Non-polar
Define Hypotonic
Less solute concentration outside of the cell.
One active transport protein is called the ___ pump which helps muscle cells contract.
Na+/K+
The head of a phospholipid is made of an alcohol and ___ group, while the tails are chains of ____
Phosphate Hydrocarbons
The cell membrane is also called the ______
Plasma
Embedded in the phospholipid bilayer are ___ that also aid in diffusion and in cell recognition.
Proteins
What is diffusion?
The movement of particles from an area of high concentration to an area of low concentration.
What does hydrophilic mean?
Water Attracting
What does hydrophobic mean?
Water Repelling
. Large molecules like ___ or carbohydrates use proteins to help move across cell membranes.
amino acids (there are several correct answers here)
The phospholipids have a hydrophilic (water attracting) _____ and two hydrophobic (water repelling) ____
head tails
integral protein function
help transport certain materials across the cell membrane
Proteins called ___ go all the way through the bilayer, while ___ proteins are only on one side.
integral peripheral
glycoproteins and glycolipids functions
involved in cell-to-cell recognition
phospholipid bilayer function
make up the bilayer
Some of the membrane proteins have carbohydrate ___ attached to help cells in recognize each other and certain molecules.
moieties (it's a fancy word that means parts)
Integral proteins are also called ___ proteins.
transmembrane
The protein that is used to pump the ions through is called a ___ protein and it changes its ___ to move the ions across the cell membrane.
transport shape
