Tour of the Cell What the cell??! Basic unit of life 3.8 BYA Coacervates prokaryotes eukaryotes Von Leuwenhoek, Hooke, Schleiden, Virchowr Microscopes & resolution Prokaryotic and Eukaryotic cells compared Figure 4.4x5 PROKARYOTIC CELL EUKARYOTIC CELL Cell diversity many sizes many shapes to suit their function Stem cells are pluripotent can differentiate to become anything embryonic vs. adult Cell Theory All living things are made of cells Cells are basic unit of life All cells come from pre- existing cells All cells Plasma or Cell membrane Boundary for cell, cellular communication, cell attachment & support; cell metabolism Cytoplasm Site of most cellular metabolism Within membrane; within organelles DNA Ribosomes to follow the directions Nucleus Genetic control center Chromatin held on chromosomes Nucleolus Makes ribosomes Boundary Interface between the inside world and the outside world of the cell Semi-permeable fluid mosaic model Acts as doors and windows to the cell Cell membrane Cell membrane proteins function Markers - ID tags for recognition Transport channels for big molecules Cell surface receptors antennae of the cell Enzymes catalysts Cell adhesion cell to cell to form tissues Scaffolding support cytoskeleton attachment cell communication & junctions Cell wall & cell membrane Plasmodesmata & Gap junctions channels b/t cells Extracellular matrix glycoprotein glue cell adhesion to form tissues Tight Junctions Anchoring junctions Organelles (found only in Eukaryotes) Organelles organize the cell little organs Allow for specialization more efficient work Membrane bound Endomembrane System System of cellular connection & communication Formed from eukaryotic infolding of cell membrane Help to further compartmentalize the cellular activities Endoplasmic reticulum Golgi apparatus Vacuoles Compare Animal & Plant cell Animal cells No cell wall Few vacuoles Nucleus centered No plastids Plant cells Cell wall Large central vacuole Nucleus pushed to side Plastids Spherosomes instead of lysosomes Chloroplasts in plant cells Figure 4.5Bx2