BZ 110 1st Edition Lecture 2Outline of Last Lecture II.What are cells?III. Why are most cells small?IV. Components of Plasma MembraneV. Function of Cell MembranesVI. Movement across membranesOutline of Current Lecture VII. Organelles of Eukaryotic Cells a. Information/Command center of cellsb. Cytomembrane systemc. Golgi apparatusd. Lysosomese. Organelles that contain their own DNAf. Endosymbiont theoryg. Cytoskeletonh. Cilia and Flagella movementCurrent Lecture2.5 Organelles of a Eukaryotic cell- Phospholipids are the main organelle of the bilayerThese 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.Information/ Command center:- Nucleus: membrane bound organelleo Genetic material is in closed within a nuclear membraneo Surrounded by a nuclear envelope, which consists of a phospholipid bilayero Inner mass contains chromatin (DNA and Protien) DNA are found as chromatino Site of transcription (DNARNA) Translated into proteins that direct chemical reactionso Chromatin- in a non-dividing cell, not condensed- Nucleolus:o Present in non-dividing cellso Contain protein and RNA used to assemble ribosomes Ribosomes are cytoplasmic structures that function in protein syntheseso Preassembling point for ribosomesCytomembrane (endomembrane) System: - Used to compartmentalize cells- Endoplasmic reticulum: continuous with the nuclear envelope and extends into the cytoplasm of the cello Rough ER: Site of protein synthesis and transport Called rough because it has a rough appearance in microscope because it is studded with ribosomes Look like tubes or channelso Smooth ER:  Doesn’t have ribosomes, looks smoother Site of lipid production, detoxification of organic molecules, and storage of calcium ions in muscle cells- Calcium is necessary for muscle contractionGolgi apparatus:- Referred to as the post office of cells- Golgi receives products from the ER- Then modifies, sorts, packages, and secretes proteins and lipids- Budding vesicle- contains modified moleculeso Either stay in the cell or are sent out of the cellLysosomes:- Garbage disposal of the cells- cytoplasmic organelles that arise from golgi bodies- stays within the cells- contain acid hydrolases (destroy / dispose of unneeded cells)- digest organelles, foreign cells- apoptosis: programed cell death (in our DNA)o example: tadpoles lose their tails when they become frogs, because of the process of apoptosis- Diseases associated with abnormal lysosomal function:o Result from enzyme deficiency, that results in an accumulation of a substrate in the lysosomes in the cello Tay- sachs, morquio syndrome, pompe diseaseOrganelles that contain their own DNA:- Mitochondria:o “power generators” of the cell o Mitochondria are the site of oxidative metabolism/ cellular respirationo ATP synthesis happens within this organelleo Divides by binary fusiono All mitochondria come from mother- Chloroplasts:o Found in plantso Site of photosynthesisEndosymbiont Theory:- See page 32 in textbook- Proposed by Dr. Lynn Margulis in 1967- These organelles that are referred to as chloroplasts and mitochondria evolved within a prokaryotic cell- Symbiogenesis: The merging of different species produce evolutionarily new forms Cytoskeleton:- Cell skeleton- Made of 3 major components:o Microtubules: largest component Cylindrical structures consisting of tublin subunits Function in movement of organelles and chromosomes In nerve cells, function in the transport of moleculeso Intermediate filaments: medium size Consist of various types of proteins  Maintain cell shape and spatial organization See different proteins depending on what tissues the cells are in- Give us incite on cancer location and spreado Microfilaments: smallest, actin filaments Consist of strings of actin molecules Highly developed in muscle cells- Function in movement and allow muscle contractionsCilia and Flagella: movement- Cilia is short and numerous compared to flagella- Internal structure of cilia and flagella the same- 9+2 pattern of microtubules- Each cell in the body may have a single cilium (primary cilium) that functions as a signal- receiving “antenna”- Necessary for development especially brain