CBIO 2200 1st Edition Lecture 4 Outline of Last Lecture I Chemistry of Life II The Chemical Elements III Electrolytes IV Isotopes and Radioactivity V Radiation and Madame Curie VI Physical vs Biological Half Life VII Water and Mixtures VIII Acids Bases and pH IX Metabolism X Carbon Compounds and Functional Groups XI Monomers and Polymers XII Carbohydrate XIII Lipids Outline of Current Lecture Chapter 2 cont d I Lipids II Proteins III ATP Other Nucleotides and Nucleic Acids These notes represent a detailed interpretation of the professor s lecture GradeBuddy is best used as a supplement to your own notes not as a substitute Chapter 3 I Cell Shapes and Sizes II Membrane Transport Current Lecture I II III Lipids a Classified as i Saturated solid at room temp ii Unsaturated has double bonded carbons iii Polyunsaturated multiple double bonds iv Essential fatty acids must obtain from your diet body can t make them b Trans Fat Cardiovascular health c Trans fatty acids d Cis fatty acids natural fats and oils e Eicosanoids 20 carbon compound derived from a fatty acid called arachidonic acid i Includes prostaglandins perceive pain present in all body tissue f Steroids a lipid with 17 of its carbons in 4 rings i Cholesterol the parent steroid from which other steroids are present 1 i e estrogen testosterone cortisol etc g Good and Bad Cholesterol i HDL high density lipoprotein good cholesterol high amount of protein in it ii LDL low density lipoprotein bad cholesterol associated with cardiovascular disease high amount of lipids in it and a low amount of protein Proteins a Greek meaning of first importance b Amino acid central carbon atom with 3 attachments i Amino group NH2 carboxyl group COOH radical group R c Proteins are polymers of amino acids d Peptide bonds are what join the amino acids in a protein together formed by dehydration synthesis i Dehydration synthesis monomers covalently bond together to form a polymer done by the removal of a water molecule ATP other nucleotides and Nucleic Acids a 3 components of nucleotides i Nitrogenous base single or double bonded C N ring ii Sugar monosaccharide iii One or more phosphate groups b ATP best known nucleotide its 3 components i Adenine the nitrogenous base ii Ribose sugar iii Phosphate groups 3 c We obtain ATP from the food we eat and our body converts it to energy for things like i Muscle contractions ii Ciliary breathing iii Active transport iv Synthesis reactions d Nucleic Acids i Monomers ii Polymers or nucleosides iii DNA deoxyribonucleic acid iv RNA ribonucleic acid three types all used for protein systhesis 1 Messenger RNA mRNA 2 Ribosomal RNA rRNA 3 Transfer RNA tRNA Chapter 3 I Cell Shapes and Sizes a All living organisms are composed of cells b Cells are responsible for all structure and functional properties that make us who we are c Cell shapes squamous cuboidal columnar polygonal many sides stellar starshaped spheroid discoid fusiform spindle shape fibrous d Human cell i Most are 10 15 micrometers microns in diameter 1 Egg cells are 100 micrometers in diameter but you still need a microscope to see it ii Need a light microscope to observe human cell iii Resolution of electron microscope reveals the ultrastructure inside of cell organisms e Basic composition of cell i Plasma cell membrane composed of protein lipids ii Cytoplasm cytosol intracellular fluid ICF inside plasma membrane iii Extracellular membrane ECF outside plasma membrane f Plasma Membrane phospholipid bilayer i Forms border of cell ii Oily film of lipids with embedded proteins 1 Lipids hydrophobic tails with hydrophilic heads II 2 Transmembrane pass all the way through membrane and peripheral on surface proteins g 98 of the molecules in our cells are lipids i Phospholipid ii Cholesterol iii Glycolipid protective coating against microorganisms iv Transmembrane proteins channels for passage of hydrophilic molecules h Functions of membrane proteins i Receptors chemical messenger ii Enzymes breakdown products iii Channels some gated molecules must bond to them for gates to open iv Cell identity markers v Cell adhesion molecule CAM attaches one cell to another i Second messenger i Chemical reaches first messenger epinephrine which binds to the surface receptor ii Receptor activates the signal to adenylate cyclase which converts ATP to cAMP second messenger the end goal is to get to the nucleus Membrane Transport a Plasma membrane barrier and gateway between cytoplasm and ECF b Passive transport requires no ATP c Active transport mechanisms require ATP d Carrier mediated mechanisms molecule that binds to it caused other molecules to be able to pass through e Passive Transport i Filtration passage of particles through selectively permeable membrane by hydrostatic pressure ii Diffusion movement of particles from area of high concentration to low concentration down concentration gradient 1 Simple diffusion a Factors affecting rate of molecule diffusion through membrane i Temperature ii Molecule weight iii Steepness of concentration gradient iv Surface area of membrane v Membrane permeability b Diffusion through lipid bilayer hydrophobic molecules c Diffusion through channel proteins hydrophilic molecules iii Osmosis flow of water from one side of selectively permeable membrane to the other from area of high concentration to area of lower concentration 1 Aquaporins proteins in the membrane increase when cells need more water decrease when cells become overly hydrated controlled by the kidney 2 Osmotic pressure when pressure is applied to membrane to stop passage of water to a certain extent a Tonicity measure of the osmotic pressure i Hypertonic concentration of water is higher within the cell than outside the cell water flows out of cell ii Isotonic water concentration is the same within and outside the cell iii Hypotonic water concentration is higher outside the cell than it is inside the cell b Effects of tonicity on Red Blood Cells i Hypertonic solution water loss of RBC causes cell to crenate shrivel ii Isotonic no net movement of water iii Hypotonic cell will gain water and lyse burst