Day 1_ Membrane Structure Notes PDF

Cell Membrane Review Determine whether each statement describes lipids (L), carbohydrates (C), proteins (P), or nucleic acids (NA). ____ Includes sugars and starches ____ DNA and RNA ____ Made of monosaccharides ____ Building block is amino acids ____ Made by ribosome ____ Stores energy for later u...

Cell Membrane Review Determine whether each statement describes lipids (L), carbohydrates (C), proteins (P), or nucleic acids (NA). ____ Includes sugars and starches ____ DNA and RNA ____ Made of monosaccharides ____ Building block is amino acids ____ Made by ribosome ____ Stores energy for later use Cell membrane is also called the PLASMA MEMBRANE and is sometimes called the phospholipid bilayer  Structure of the cell membrane WHAT IS IT MADE OF? 1. Phospholipids: Creates the boundary Molecule composed of two parts: wate a. Hydrophilic (Polar) Head: ○ Hydrolovin = r ○ Phil = g This part of the phospholipid is Attracted to water molecules Contains phosphate WHAT IS IT MADE OF? b. Hydrophobic (Nonpolar) Tails: ○ Hydro = wate ○ Phobos= fearing r This part of the phospholipid is Repelled by water molecules Contains Fatty Acids (Lipids) T0DAY’S KEY IDEA Orange: Phospholipids Proteins: Help transport materials in and out of cell T0DAY’S KEY IDEA Orange: Phospholipids Purple: Proteins  CARBOHYDRATES Carbohydrates: Signal and identify particles outside the cell. Acts like an antenna T0DAY’S KEY IDEA Orange: Phospholipids Purple: Protein Blue: Carbohydrates Cholesterol: Keeps membrane fluid Prevents lipids tails from sticking together T0DAY’S KEY IDEA Orange: Phospholipids Purple: Proteins Blue: Carbohydrates Green: Cholesterol Structure Remember the main purpose of the cell membrane. Should it be easy for things to enter and leave?  WHAT ARE THE FUNCTIONS OF THE CELL MEMBRANE? Boundary (Flexible and Fluid) ○ Cell can move around and change shape FUNCTIONS OF CELL MEMBRANE Maintain Homeostasis (transport) ○ Transport materials in and out of cell to maintain balance WHAT ACTUALLY ENTERS AND LEAVES CELL Things that enter the cell: ○ Food, Water, Oxygen Things that leave the cell: ○ Waste, Carbon Dioxide  Selectively Permeable What does it mean to be selective? What does it mean to be permeable? What molecule is the membrane letting through? THE PLASMA MEMBRANE IS: Selectively Permeable: Only some particles are able to pass in and out of cell easily ○ Ex: Water can move across membrane but sugar can’t  Main function of the cell membrane 1. Made up of proteins and phospholipids that control what enters and leaves the cell to help maintain homeostasis.