BIOL 120 1st Edition Lecture 9 Outline of Last Lecture I Protein Structure a denatured renatured II Catalyst and Enzymes a catalyst activation energy enzymes III Cell Structure Intro a cell theory resolution IV Prokaryotic cells beginning a Plasmids Outline of Current Lecture I Prokaryotic Cells cont a flagella II Eukaryotic Cells a nucleolus nuclear envelope nuclear pore chromatin Rough ER endocytosis pinocytosis thylakoids grana stroma III Cell to cell interactions and connections Current Lecture I Prokaryotic cells 1 Internal Structures A Most have 1 supercoiled circular chromosome located in the nucleoid 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 B Plasmids C Ribosomes consist of RNA molecules and protein D Many have internal photosynthetic membranes i e bacteria 2 External Structures A Flagella tail like features that spin around to move the cell B Most have a cell wall i Bacterial Archaeal cells have tough fibrous layer that surrounds the plasma membrane as a cell wall composed of peptidoglycan ii Cell walls of fungi plants and other protest are different iii many have an additional layer outside the cell wall of lipids called capsule II Eukaryotes 1 These cells are compartmentalized A it is difficult for large molecules to travel across the large cell solved by breaking up the cell into smaller membrane bound organelles i Advantages a separation of incompatible chemical reactions b increases the efficiency of chemical reactions 2 Differences from prokaryotes A Eukaryotic chromosomes are inside the nucleus which is a membrane bound compartment B Eukaryotic cells are bigger C Eukaryotic cells have lots of internal membrane bound compartments D Eukaryotic cells have a diverse and dynamic cytoskeleton 3 Animal Cell A 4 Plant cell A 5 The nucleus A stores genetic information B The nucleolus region where ribosomal RNA is synthesized C Nuclear envelope a double membrane surrounding the nucleolus with nuclear pores to control what goes in and out of the nucleus D Has linear chromosomes instead of circular E has Chromatin chromosomes and proteins which are in charge of folding 6 Endomembrane System A a series of membranes throughout the cytoplasm divides cell into compartments B a distinction between eukaryotes and prokaryotes 7 Rough endoplasmic reticulum A rough ER a network of membrane bound tubes and sacs studded with ribosomes interior is called the lumen B It is continuous with the nuclear envelope C Used to synthesize proteins and then folded and processed in the lumen 8 Smooth ER A Similar to rough ER but lacks the ribosomes B Enzymes within the Smooth ER synthesize fatty acids and phospholipids used for membranes C Also breaks down poisonous lipids and stores calcium ions 9 Golgi apparatus A Golgi apparatus a flattened stack of interconnected membranes B Function transport system a packs molecules into packages vesicles b distributes molecules synthesized at one location to be used at another C cis is towards ER and trans is towards outside 10 Ribosomes A are non membranous and not considered organelles B large and small subunits containing RNA molecules and protein C attached to rough ER or free in the cytosol D made of rRNA E Functions a protein synthesis primary structure i also needs mRNA and tRNA 11 Microbodies A they are enzyme bearing membrane enclosed vesicles B Peroxisomes a contain enzymes involved in oxidation of fatty acids hydrogen peroxide produced as a by product that is broken down by catalase b in plants it is glyoxysomes use enzymes that oxidize fats to form a compound used to store energy 12 Lysosomes A they are single membrane bound structures containing about 40 different digestive enzymes B Found in animal cells C Function used for digestion and waste processing D Delivered through a phagocytosis b Autophagy E Endocytosis a process by which the cell membrane can pinch off a vesicle to bring outside material into the cell F Pinocytosis a process that brings fluid into the cell c receptor mediated endocytosis 13 Vacuoles A they are in plant not animal cells B Functions a storage turgidity etc b contain digestive enzymes c some specialized for digestion d most used for water and ion storage C Types a central vacuole b storage vacuoles c contractile vacuole some fungi and protists 14 Mitochondria A bounded by membranes outer and inner B Cristae finger like projections that give more surface area C on the surface and within are proteins that carry out oxidative metabolism ATP synthesis D They have their own DNA and make their own ribosomes 15 Chloroplast A found in plant and algal cells that have a double membrane and container their own DNA like mitochondria B contain thylakoids membrane bound flattened vesicles C That are stacked into piles known as grana D outside of these is the solution called stroma E Function covert light energy to chemical energy photosynthesis 16 Cell walls A found in plants fungi and many protists B plants and protists made of cellulose C Fungi made of chitin 17 Cytoskeleton A a network of protein fibers that support the shape of the cell and keeps organelles in fixed locations B A dynamic system that is constantly forming and disassembling C Aids in cell movement and transports materials within cell D Three types of fibers a microfilaments actin filaments two protein chains loosely twined together b microtubules dimers of alpha and beta tubulin subunits c intermediate filaments very stable 18 Centrosomes A region surrounding centrioles help move chromosomes during cell division B found in animal cells and most protest C plants and fungi lack them 19 Extracellular matrix A Animal cells lack a wall secrete a mixture of glycoproteins into the area around them i e collagen which forms a protective layer over the cell surface III Cell to cell interaction and connections 1 interactions A surface cells give the cell an ID which other cells read and react a glycolipids are the most tissue specific cell surface markers b MHC proteins allow for the recognition of self and nonself cells by the immune system 2 Connections A Tight junction Connect the plasma membrane of adjacent cells B Anchoring junction attaches cytoskeletons of neighboring cells C Communication junction chemical or electrical signal passes directly from one cell to an adjacent cell D Plasmodesmata specialized openings in cell walls similar to communication