Lecture 1 (The Cell) - Biophysics (PHY261) PDF

Lecture 1 The Cell Biophysics (PHY261) The Cell 2  Definition of the Cell A cell is the smallest unit that is capable of performing life functions. 3 Cell Theory 4  Cel...

Lecture 1 The Cell Biophysics (PHY261) The Cell 2  Definition of the Cell A cell is the smallest unit that is capable of performing life functions. 3 Cell Theory 4  Cell Theory All living things are made up of cells. 5  Cell Theory All living things are made up of cells. Cells are the smallest working units of all living things. 6  Cell Theory All living things are made up of cells. Cells are the smallest working units of all living things. All cells come from preexisting cells through cell division. 7 Cell Size 8  Characteristics of All Cells A surrounding membrane 9  Characteristics of All Cells A surrounding membrane Protoplasm – cell contents in thick fluid 10  Characteristics of All Cells A surrounding membrane Protoplasm – cell contents in thick fluid Organelles – structures for cell function 11  Characteristics of All Cells A surrounding membrane Protoplasm – cell contents in thick fluid Organelles – structures for cell function Control center with DNA 12  Cell Types Prokaryotic Eukaryotic 13  Eukaryotic Cells Nucleus bound by membrane Include fungi, protists, plant, and animal cells Possess many organelles Protozoan 14 Representative Animal Cell 15  Plasma Membrane Contains cell contents Double layer of phospholipids & proteins 16 17  Phospholipids Polar o Hydrophylic head o Hydrophobic tail Interacts with water 18 Membrane Proteins 1. Channels or transporters o Move molecules in one direction 2. Receptors o Recognize certain chemicals 19 Membrane Proteins 3. Glycoproteins o Identify cell type 4. Enzymes o Catalyze production of substances 20  Movement Across the Plasma Membrane A few molecules move freely o Water, Carbon dioxide, Ammonia, Oxygen Carrier proteins transport some molecules o Proteins embedded in lipid bilayer 21 22  Cytoplasm Viscous fluid containing organelles components of cytoplasm o Interconnected filaments & fibers o Fluid = cytosol o Organelles (not nucleus) o storage substances 23 Membranous Organelles Functional components within cytoplasm Bound by membranes 24  Nucleus Control center of cell Double membrane Contains o Chromosomes o Nucleolus 25  Nuclear Envelope Separates nucleus from rest of cell. Double membrane 10-50 nm apart. The outer nuclear membrane is continuous with the membrane of the RER. Has pores. 26  DNA Hereditary material Chromosomes o DNA o Protiens o Form for cell division Chromatin 27  Nucleolus Most cells have 2 or more Directs synthesis of RNA Forms ribosomes 28 Endoplasmic Reticulum Helps move substances within cells Network of interconnected membranes Two types o Rough endoplasmic reticulum o Smooth endoplasmic reticulum 29  Rough Endoplasmic Reticulum Ribosomes attached to surface o Manufacture proteins o Not all ribosomes attached to rough ER 30  Smooth Endoplasmic Reticulum No attached ribosomes Has enzymes that help build molecules o Carbohydrates o Lipids 31  Golgi Apparatus Involved in synthesis of plant cell wall Packaging & shipping station of the cell 32 Golgi Apparatus Function 1. Molecules come in vesicles 2. Vesicles fuse with Golgi membrane 3. Molecules may be modified by Golgi 33  Golgi Apparatus Function (Continued) 4. Molecules pinched-off in separate vesicle 5. Vesicle leaves Golgi apparatus 6. Vesicles may combine with plasma membrane to secrete contents 34 35  Lysosomes Contain digestive enzymes Functions o Aid in cell renewal o Break down old cell parts o Digests invaders 36 Mitochondria 37  Mitochondria The cellular power plant. 38  Mitochondria The cellular power plant. They generate most of the Adenosine triphosphate (ATP) that is used by the cell as a source of chemical energy. 39  Mitochondria The cellular power plant. They generate most of the Adenosine triphosphate (ATP) that is used by the cell as a source of chemical energy. Have their own DNA. 40  Mitochondria The cellular power plant. They generate most of the Adenosine triphosphate (ATP) that is used by the cell as a source of chemical energy. Have their own DNA. Bound by double membrane. 41  Mitochondria The cellular power plant. They generate most of the Adenosine triphosphate (ATP) that is used by the cell as a source of chemical energy. Have their own DNA. Bound by double membrane. mitochondria are involved in other tasks such as signaling, cellular differentiation, control of cell cycle and cell growth. 42  Mitochondria Break down fuel molecules (cellular respiration) o Glucose o Fatty acids Release energy o ATP 43 Questions?? 44