Cell Membrane Cell Membrane Location the cell Function

Cell Membrane

Cell Membrane? Location? ________ the cell Function? 1. ________ and _____ for the cell 2. Regulation of what ____ and _____ the cell WHY? -Essential in order to maintain *homeostasis within the cell *maintaining _____ internal conditions

Composition of Cell Membrane Phospholipid Bilayer 1. ________: § § Hydrophilic Head; “water-_____” Hydrophobic Tail; “water-_____” 2. Bilayer § _______-layers (of phospholipids)

Composition of Cell Membrane ______ embedded throughout phospholipid bilayer Integral Proteins: ______ the width of the cell membrane ______ Proteins: Located on one side of the cell membrane (or on the ‘periphery’) A variety of different ____ of proteins within the cell membrane, each with different ______

Composition _______: another lipid that maintains the _______ stability of the cell membrane Carbohydrates: allow for cell-tocell _______; a “fingerprint” for each cell Allows for the immune system to recognize ‘foreign’ cells and attack them Attached to proteins or phospholipids on _____ layer of cell membrane

Fluid Mosaic Model Break it down: FLUID: The cell membrane is ______ due to the lipid “tails” on its interior; they “wiggle” This means that the cell membrane is pliable The cell membrane has the consistency of olive oil at body temp. MOSAIC: _________ of different types, ________ positioned throughout the membrane create a “mosaic” appearance The cell membrane is a constantly moving assemblage of parts.

Cell Membrane Function Transport of molecules from one side of the membrane to the other in order to maintain homeostasis within the cell. _______ Permeable: Only _____ substances can move across the membrane while others cannot. _____, non-charged molecules (H 20, CO 2, etc. ) can ____ cross the cell membrane. This is referred to as Passive Transport: molecules are ‘freely’ or ‘passively’ traveling through the cell membrane This occurs through one of two ways: ______ or ______ diffusion

Passive Transport: Diffusion No ______ is required Diffusion: the movement of molecules from a _____ concentration to a _____ concentration until equilibrium is reached Concentration: the amount of solute in the solvent ______: dissolved substance (in the solvent) solvent: the liquid containing the dissolved substance Equilibrium: occurs when the _____ concentration is the same throughout the system; ______ on both sides of the membrane

Passive Transport: Facilitated Diffusion A form of Passive Transport (so no _____ required) Facilitated Diffusion: ______ molecules (that are unable to passively cross the cell membrane) are “carried” through via a channel protein. Specific protein channels carry specific types of molecules For example: _____ is transported across the cell membrane via facilitated diffusion