Ch. 3 Cells Part 1-2 PDF

Part 1: Overview of Cells, Cell Membrane  Basic unit of structure & function 200 different cell types Made of C, O, H, N + trace elements 3 main parts: 1. Plasma membrane 2. Cytoplasm 3. Nucleus Loading… ...

Part 1: Overview of Cells, Cell Membrane  Basic unit of structure & function 200 different cell types Made of C, O, H, N + trace elements 3 main parts: 1. Plasma membrane 2. Cytoplasm 3. Nucleus Loading…  nucleus orgla Eukaryote-organismsthathavea or nucleus e bacteria organelles g.. prokaryote - doesn't have Loading…  Kell Membrane Function: enclose cell contents, control exchange of substances with environment, cell communication Made of: Lipid bilayer Cholesterol Glycolipids Proteins  cell -how we describe the membrane ↳ many different components to it Proteins float in fluid lipid bilayer poler hydrophobic friends they have stay w/ hydrophobic to - ↳ are where the tails are Polar  Phospholipid:main components of cell membrane 1. Polar/hydrophilic (water-loving) “head” Nonpolar/hydrophobic (water-fearing) “tail” 1. Cholesterol 20% of membrane lipid Stabilize membrane Maintain fluidity 1. Glycolipids Lipid + sugar attached ew · 5% membrane lipid For cell recognition ↳ signalling/communication Loading… glycolipid 1. Integral Proteins Inserted into lipid bilayer Have both hydrophilic & hydrophobic regions Functions: enzymes, transport, receptors (relay messages) somemolecules willhave use a he glucose. is polar ⑫ e g Dr Cor. Top small non-polar things into the cell easily ↓.. molecules that can come integral proteins Y Bottom is non polar 1. Peripheral Proteins Attached loosely to membrane easily around - can move Functions: support, enzymes, movement, linkage peripheral protein  protein + sugar attached Serves as specific biological marker cell recognition Sugar I I glycoprotein protein Transport Receive chemical messages Maintain cell shape Enzyme activity Intercellular joining Cell-cell recognition “ID tags” Part 2: Membrane Transport  Interstitial fluid: Fluid outside cells Rich, nutritious “soup” – amino acids, sugars, fatty acids, vitamins, hormones, salts, wastes Loading… Selective Permeability: Plasma membrane only allows some substances to enter cell Nutrients in, wastes out By passive or active transport doesne  dimpfusimnoche s solute move) Osmosis needs channels No energy (ATP) needed Molecules move down concentration gradient from HIGH LOW concentration - Types: diffusion, filtration  Nonpolar & lipid-soluble substances diffuse directly through lipid bilayer Eg. (O2, CO2, fat-soluble vitaminsIonly small things a EXCEPT Loading… can come in brane water /sometimes Anthingthatpolarventcomintecl substances go are able to through because: Nonpolar slipid soluble the hydrophobic the tails They're passing through the same properties as. They have tails can't thats polar orhas a charge NB : Anything easily go through.  Transport proteins (carrier or channel proteins) needs chanel & assist molecules across membrane a carrier Eg.I glucose, amino acids, H2O, ions- facilitated come in via diffusion NB: Protein carrier changes shope NB : Protein channel doesn't change shape (channel only for water) carries channel channel  Water-filled channels Eg. ions  Binds to molecule, changes shape, ferries it across membrane Eg. glucose transporter  a more conc solution dilute solution to. Goes from a Diffusion of H2O Aquaporins: channel proteins for H2O passage  soa volue Loading… the membrane is onlypermeable  Ability of solution to change shape or tone of cells by changing water volume Isotonic = equal concentration solutes Hypertonic = higher conc. of solutes Hypotonic = lower conc. of solutes  NB : In plants if you place it in a hypertonic shrives up solution it also. + because plant cells have a not burs Butit will retains its shape wall which all from Water moves hypo > hyper -  Energy (ATP) is needed!! Move molecules against concentration gradient from LOW HIGH concentration Types: Primary and Secondary transport increases the magnitude of the gradient · Active  Directly uses ATP to drive transport Eg. Ca2+ pump, H+ pump, Na+-K+ pump · 3 Net for 2 + 3 Nat for zet Low conc. > - High cone Sodium-Potassium Pump pbinds to pun changesatheof pump gets hydrolyzed to (reacts wl water ADP make Pb , is hosphat changes shape  Move more than 1 substance at a time Symport: 2 substances moved in same direction Na , Glucose cotransport g a. Antiport: 2 substances cross in opposite directions. Na , pemp g.e. Eg. cotransport of sugars, animo acids, ions  ↳ becauseit doesn't directly use atp only inthe beginning ulpans intestival cells Happensin the i goes from low to high sodiumis beingits gradint egainst forced set car soit us / a fro creates the electrochemical goes gradient Anteport Inside of all is symport thathe outside NB: much more negative ( T I primary Contrappedcondary ~ Thingadriving Nat un : Y Electroeal Outside (chemical grad :..a t of Nat conc :) There is. it positive lot of sodium come making very outside 2) There's insideelectrical grad) a the negative attracts Na to gradient  Active Transport Type of Fluid & large particles transported across membranes in vesicles (sacs) Exocytosis: “out of cell” – eject substances Endocytosis: “within the cell”- ingest substances  Cell eats large particles Phagocytosis: (cell eating) – engulf large or solid material eg. WBC engulf bacteria Bei MgS  easaller particles Pinocytosis: (cell drinking) – fluid w/dissolved molecules Eg. intestinal cells  Receptor-mediated endocytosis: concentrate specific substances (ligands) that bind to receptor proteins Eg. insulin, iron, cholesterol CHAPTER 3: CELLS Part 3: Cytoplasm & Nucleus CYTOPLASM  CYTOPLASM Between plasma membrane & nucleus Three elements: Cytosol: fluid Eg. water, proteins, salts, sugars little- > Loading… Organelles: specific functions Organs Inclusions: chemical substances that vary depending on cell type Eg. glycogen (liver), lipid droplets (fat cells), melanin (skin & hair) ORGANELLES “little organs” Specialized compartments specific functions Membranous = membrane-bound Mitochondria, peroxisomes, lysosomes, ER, Golgi apparatus Nonmembranous = no membrane cytoskeleton, centrioles, ribosomes NB : don't regenerate RNA in a process called NB : DNA becomes neurous ↳ doesn't have centrides transcription transcription DNA- > RNA in syribosomes Ired dots) ↓ translation made Protein ↳ where proteins are reticulum Brough endoplasmic ↳ found in the cytoplasm Limportant for cell division in mitosis Loading… ↳ In the nucleus ↳ makes ribosomes smallest largest  ENDOMEMBRANE SYSTEM System of organelles that work to 1. Produce, store, export biological molecules 2. Degrade harmful substances ~ degradesharmfu reses, testicles Nuclear envelope, rough ER, smooth ER, Golgi apparatus, secretory vesicles, lysosomes ↳ breaks down , destroy, remove ENDOMEMBRANE SYSTEM USPS operates likes sends stuff where its supposed to go of its mods i... one ( the process of adding Glycosilation - suger to a protein NUCLEUS  NUCLEUS Control center contains DNA Most cells have only 1 nucleus Multinucleate: many nuclei (muscle, some liver cells) Anucleate: no nucleus (mature RBC) Three main structures:. Nuclear envelope. Nucleoli. Chromatin ↳ makes ribosomes Multinucleated Muscle Cells Anucleated Red Blood Cells Multinucleated Liver Cells NUCLEAR ENVELOPE Double membrane barrier surrounds nucleus Outer part continuous with Rough ER Nuclear pores: control entry/exit of molecules Rna comes out of i Loading… NUCLEOLUS (NUCLEOLI) Dark-staining bodies in nucleus 1-2 per cell Site where ribosomes are made CHROMATIN DNA is negatively charged are positively charged Histores C Chromatin = DNA + Proteins Nucleosome = DNA wrapped around 8 histone proteins Histones allow for compact and orderly packing of long DNA molecules During cell division, chromatin condenses to form chromosomes. MITOSIS Not on Test Part of cell division Replicated DNA divided into 2 daughter cells Usually lasts about an hour Interphase prophase metaphase anaphase telophase & cytokinesis