GBIO 106 1st Edition Exam #2 Study Guide LECTURE 8: Cell Structure and Function: -Robert Hooke: Coined the term "cells". He worked with Sir Isaac Newton. -Leeuwenhoek: Discovered living cells. -Schleiden and Schwann: All living things are composed of cells. Cells are the basic unit of life,if all living things are made of cells. These hypotheses have become known as cell theory. -Virchow: Studied leukemia patients. All cells come from pre-existing cells. -General characteristics of cells: -Plasma membrane: Protects, absorbs, communicates. -Genetic information: DNA; blueprint of how to build new cells. Also all the instructions on how to perform chemical reactions. -Chemical reactions: Used for energy for cells. -Cytoplasm: All material inside the cell and outside the nucleus. Holds water, salt, and organic molecules. Some cells have organelles. 70-90% water. -Two major types of cells:-Prokaryotic: No nucleus. Bacteria (strep, staph, e. coli, anthrax). Archaea live in extreme habitats. -Eukaryotic: Have a nucleus. In living things. Parts of a Cell: Membrane-bound Organelles-Nucleus: Control center of the cell.-Chromatin: DNA and protein. Later on has to do with chromosomes. -Nucleolus: Where ribosomes are made. -Ribosomes: No membrane. They are a place where proteins are built; a table to work on. Two types, some are mobile, some are stationary. -Free ribosomes: Proteins made here will function as enzymes within the cytosol. -Bound ribosomes: Attached to rough ER. Proteins are made specific, like lysosome enzymes, membrane proteins, or secretory proteins. -Endoplasmic Reticulum: Network of membrane. Two types.-Rough ER: Contains ribosomes. Involved in protein synthesis, membrane production, and transporting. -Smooth ER: Does not make proteins. Involved in lipid and carb synthesis. In the liver it helps detox drugs.-Golgi complex: A bunch of flat sacks of membrane, looks like pita bread. The cell's warehouse. Stores, modifies and distributes molecules. -Vesicles: Small sacks of membrane. Carry materials around the cell.LECTURE 9: -Data in DNA orders a secretion to be made. RNA lays out instructions and is sent to rough ER into the bound ribosomes. Vesicles carry the protein to the Golgi body. There it will either be stored or it will be modified. Then it can be put back in a vesicle and secreted from the cell. The vesicle is used as a new bit of cell membrane. DNA -> RNA -> Protein ; Nucleus -> Rough ER -> Vesicle -> Golgi -> Vesicle -> Plasma membrane. -Lysosomes: Cell's digestive system. Essentially a bigger vesicle with acid that acts as a stomach of sorts. Can digest molecules, and even complete microorganisms and defective organelles. -Mitochondria: Oval, round or tubular organelles made from a double membrane system. Thereis an inner and outer membrane. Location of aerobic respiration. -Cristae: Formed from folding of inner membrane. -Matrix: Inner space that contains enzymes and breaks down food molecules. -Cytoskeleton: Network of 3 different protein filaments that are responsible for shape, internal organization, and movement of the cell. Only in eukaryotic cells. -Microtubules: Guide vesicles through the cell to form cilia and flagella. -Microfilaments: Help amoeba and WBCs crawl and cause muscle cells to contract. -Intermediate filaments: Networks of these filaments help determine a cell's shape. PLANT CELLS: Organelles exclusive to plants-Cell Wall: causes pressure within the cell by pushing back against stored water. -Chloroplasts-Central Vacuole: balloon that holds water and creates pressure. LECTURE 10: -Chloroplast: One of many types of plastids. This is where photosynthesis happens. -Thylakoids: contain chlorophyll which traps light energy. Stacks of green disks inside the chloroplast. -Stroma: Space not containing chlorophyll where CO2 is turned into glucose. Other Plastids: -Amyloplasts: Store starch-Chromoplasts: store pigments of color, like red, orange, yellow for the flowers. -Vacuoles: In animals, vacuoles are usually temporary. In plants, they are permanent. It maintains the cells water balance. -Turgor pressure: pressure of water in the vacuole that pushes the cytoplasm against the cell wall.-Storage: pigments, ions, proteins, and poisons for defense. -Disposal of metabolic waste/toxinsThe Plasma Membrane-All cells have a membrane. It isolates the cells contents, and regulates what moves in and out of the cell. The fluid mosaic model is the most accurate model of the cell membrane. The fluid portion is made of phospholipids and the mosaic part is made of proteins. -Phospholipid bilayer: Two layers of phospholipids. -Membrane proteins: move substances across the membrane and communicating with other cells. -Transport proteins: form channels or act as carriers. Shapes specifically fit to certain things. -Receptor proteins: when a specific molecule binds to them, it triggers a specific cellular response, as with secretion and initiation of cell division. -Recognition proteins: serve as cells ID tag or surface attachment sites. LECTURE 11:-Cholesterol makes the bilayer stronger and less permeable to water-soluble substances like ions and sugars. Basically a sealant for the cracks in the cell membrane. These are LDLs ("bad"cholesterol). Necessary for healthy cell membranes. Cell membrane has to be flexible, to allow itto flex, expand and move. -The plasma membrane does not allow most dissolved substances to pass through. It is selectively permeable. Water and oxygen move freely through the cell membrane because of how essential they are. Smaller molecules move faster because they have less resistance. -Types of Transport: -Passive transport: Simple diffusion, osmosis, facilitated diffusion. "Go with the flow from high to low". Does not require ATP/energy. -Simple diffusion: Molecules moving from high to low concentration. The concentration gradient is the difference in concentration of a substance between two areas. Brownian motion has to do with the random motion of molecules. It is influenced by temperature and concentration gradient. Smaller molecules move faster, and diffuse faster. -Osmosis: Movement of water molecules from high to low concentration through a selectively permeable membrane. Osmosis is also affected by temperature and the concentration gradient. Solutes are dissolved substances, where solvents are the liquid in which things are being dissolved. Isotonic means that there are equal amounts of solute inside