Week 1 The Cell PDF

The Cell Module w/ Lecture Notes Below September 11, 2023 8:42 AM Intro and Cell Physiology Week 1 Page 1 Cells are the basic unit of all living organisms Week 1 Page 2 Week 1 Page 3 - Atoms are building blocks of mocs: 0.01 to 0.1nm Atoms have subatomic particles: protons, neutrons, and...

The Cell Module w/ Lecture Notes Below September 11, 2023 8:42 AM Intro and Cell Physiology Week 1 Page 1 Cells are the basic unit of all living organisms Week 1 Page 2 Week 1 Page 3 - Atoms are building blocks of mocs: 0.01 to 0.1nm Atoms have subatomic particles: protons, neutrons, and electrons Neutrons, no charge, located between protons, which helps keep nucleus together Electrons circulate around nucleus If equal number of protons and electrons, they are neutral - Week 1 Page 4 Week 1 Page 5 - Protons will change the number of electrons that circulate around them, defines the type of element - Different elements arranged by protons/atomic # - If atom gives up or gains an electron, becomes an ion, either negative or positively charged - Ex. Ca, has lost 2 electrons, thus 2+ positively charged Week 1 Page 6 - Ex. Ca, has lost 2 electrons, thus 2+ positively charged Week 1 Page 7 How atoms interact Ionic & covalent bonds, forces that hold together Compound - atoms of 2 or more elements Ionic - when electron is transferred, Covalent - sharing electron between 2 atoms, single bond ( sharing 2 electrons), double bond, triple bond - Are electrons shared equally? Nonpolar bond - Electrons shared unequally? Polar covalent bond, ex. H & O2 atoms interacting to make water - Week 1 Page 8 Week 1 Page 9 Week 1 Page 10 97% of human body made of 6 compounds: carbon, O2, nitrogen, H2, sulfur, phosphorus - - 4 key categories: - Week 1 Page 11 Week 1 Page 12 - Body is organized with basic building blocks - Then cells work together with tissues and organs for homeostasis - Will focus how all work together to maintain homeostasis Week 1 Page 13 Week 1 Page 14 Week 1 Page 15 Week 1 Page 16 Week 1 Page 17 Week 1 Page 18 - Function: separate cellular fluids from extracellular fluids & cellular activity: - 4 functions of PM: ○ Physical isolation (cytosol from extracellular fluid ○ Regular exchange of envt: entry and exit of ions, nutrients, elimination fo ewaste and secretory products i.e. enzyomes and hormones ○ Communication between cells and envt - cells must inegreate in tissues, and tissues must work with organs and organs need to work with body, so adjacent cells nee to have physiological electroical or chemical signallying ○ Structural support for rigidty for cell - glycoproteins(outermembrane surfaces), carbohydrates attached to proteins and lipids are biological markers for cell recognition Transmembranous proteins Glycohalix (sugar on extracellular side), helps with recognition information between cells Week 1 Page 19 Week 1 Page 20 - Double bi-layer of lipids and dispered proteins Polar hydrophillic regions (facing fluid) Internal is the nonpolar hydrophobic region 3 types of lipid mocs: phospholipids, glycolipids, cholesterol ○ Glycolipids bounds with carbohydrate, and found on outer membrane ○ Phospholipids:  Hydrophili heads are polar, require phosphate group  Nonpolar hydrophic group contain fatty acids that require water  Not rigid, flexible structure, selective in what it lets in, large hydrophilic mocs can't pass membrane easily, but smaller hydrophilic mocs like O2 can slide through Semi-permeable membrance Week 1 Page 21 Week 1 Page 22 - Membrane spanning proteins - completely through bilayer 10-15 types of proteins in bilayer Transport mocs, relay signals, structure to maintain shape Cell junctions Enzymatic activity and catalyst activity Highly specific receptors Can trigger events within the cell Week 1 Page 23 Can trigger events within the cell Fluid part of cytoplasm, intrcellylar fluids, intragelatinous, - Ions, waste particles, - Cytoplasm = cytosol + organelles Week 1 Page 24 Week 1 Page 25 Membranous (double, inner and outer) - ATP production in ATP - unique DNA and RNA - Powerhouse - # of mitochondria depends on how much E the cell needs - Enzymes, ribosomes, granules - Inner membrane, cristae, ATP production, eletron transport chain Powerhouse of the cell, b/c makes ATP, currency in which cell does its job Cristae in double membrane Mitochondria has it's own DNA and RNA --newer information suggests that this DNA comes from maternal AND paternal line. Week 1 Page 26 Week 1 Page 27 Week 1 Page 28 - Membranous - Smooth - w/o ribosomes, synthesis for FA, steroids, lipids, regulation of Ca ion storage - Or rough - ribosomes, site of protein synthesis, modifies and folds proteins getting ready for packaging, inserted into PM or secreted to cell - ER is always connexted to nuclear envelope, b/c signals coming from nucleus - Ribosomes are non membranes, made of large and small subunits made by nucleolus, comes together in cytoplasm, can be free or attached to ER Continuation of the nuclear envelope Ribosomes - 2 subunits, responsible for making proteins, if a cell has a lot of ribosomes, the cell must be making a lot of protein - SMOOTH ER:thus if cell doesn't have ribosomes, the smooth ER makes lipids(cholesterol), Ca2+ sequestration Week 1 Page 29 - Modify concentrate sort , package, tranpsort proteins or lipids received from ER - Forms secreotry vesicles that sedns proteins out of cell via exocytosis into extracellular fluid - ***review this slide for the steps that occur*** Golgi is usually located outside the ER, double membrane It packages items for transport ex protein, then released outside cell via exocytosis Some items are packaged differently based on their function Week 1 Page 30 Week 1 Page 31 - Secretory vesicles - paakages of cell secretions transported within or outide cells, contains proteins, hromones or NT that are produced by ER or golgi - Most vesicles have speciaized functions or materials Week 1 Page 32 - Most vesicles have speciaized functions or materials - Lysosomes - membranous, over 60 types of enzymes withtin diff lysosomes, role is to clean up worn out or damaged ornalles and kill bacteria, protextive for cell, only activated in acidic conditions, packaged in golgi, enzymes are inactive when initially released as a safety mechanism, H ions are pumped into lysosomes and enzymes are activated ex. Tay Sachs - inherited lysosomal disease - Autophagosomes - older or unneeded organelles deliver to lysosomes for digestion - Peroxisome, membranous, using oxidase or catalyse to toxify or neutralize free radicals, found in liver, key role ot detofiy - Proteasomes: barrel shaped structures when dmaged or dysfunctionanl rpoteins need to be removed, these protein complexes with protein digesting enzymes degrading unneeded or damaged proteins by proteolysis, proteins tagged by ubiquitin, and smaller components are recycled Lysosomes: Vacuoles helps to dispose organelles? Pumps in H+ ions, which lowers the pH Ex. Tay Sachs- their lysosomes don't destroy properly, so they accumulate gangliosides?? Peroxisomes - drug detoxification Week 1 Page 33 - Fibers provide strength, stabilize struture, support, and transport Cytoskeleton: - Microtubules (dysfunction related to Alzheimer's Disease) Week 1 Page 34 Week 1 Page 35 Week 1 Page 36 - Found near nucleus, made of 2 parts: 2 centrioles, pericentriolar matrix Each centrioles: 9 cluster of 3 MTs, total 27MTs, arranged in circular patterns MT assemble tubulin mocs into MTs Surrounding centrioles, pericentriolarm matrix, ring shaped complexes of tubulin During cell division, centrosomes replicate and direct movement of DNA Cells too mature to under cell divion lack centrioles Week 1 Page 37 Week 1 Page 38 Most cells have 1 nucleus, RBCs none, SK have many Cell's control center Double membrane barrier, separating nucleus from cytoplasmic compartment Both membranes have pores to enable communication, contain large protein complexes with central channel. Ions and small mocs move freely through channel when open, but large proteins and RNA to transport require energy, this restricts DNA to nucleus and various enzymes to either cytoplasm or nucleus - The nucleolus is inside nucleus to produce RNA for ribosomes - In nucleus, chromosomes, which exist as a tangled mass of entagled chromatin in interphase cells, this ontains DNA, containing genome which is unique to every individual - - How cells communicate with other cells in body to maintain homeostasis Week 1 Page 39 How cells communicate with other cells in body to maintain homeostasis Week 1 Page 40 - Cells may communication directly via GJ or chemical messegers - Autocrine and paracrine - chemical messenger through extracellular fluid binds to receptor on same cell or nearby cell - Nerve - rapid transmission of Aps over long distances and release of NT at synapse - Endocrine - release of hormone into bloodstream and binding of hormone to a specific targe cell receptor - Neuroendocrine - release of hromone from nerve cell and transport of hormone from blood to a distance target cell, which will bind to a specific receptor Week 1 Page 41 Week 1 Page 42 Week 1 Page 43 Week 1 Page 44 Week 1 Page 45 Week 1 Page 46 Week 1 Page 47 Week 1 Page 48 Communication: - Junctions** ex. Gap junctions etc. - Types of communication - paracrine, autocrine Week 1 Page 49