| Front |
Back |
| What does the plasma membrane do? | Controls passage of material into & out of cell (acts a barrier b/w internal & external enviro) Basic structural unit (phospholipid bilayer); Membrane proteins-amphipathic |
| What type of proteins make up the membrane proteins? | Integral proteins, Extrinsic Proteins, Glycoproteins |
| Integral Proteins | Extend through entire membrane (Transmembrane) must have hyrophobic & hydrophilic regions |
| Extrinsic Proteins | Assoc. w/ either cytoplasmic or extracellular region of membrane |
| Glycoproteins | Covalently linked to sugar residues on outside of cell. Sugar acts as recognition site |
| Membrane proteins serve what functions? | Enzymes, Transport, & Receptors |
| What is the purpose of the nucleus? | A repository of genetic information |
| What is the nuclear envelope? | A double membrane made up of nuclear pores which regulate passage of material b/w nucleus and cytoplasm |
| What is DNA? | 2 comlimentary strands of nucleotides held together by hydrogen bonds b/w bases |
| Chromatin DNA is packaged with what type of proteins? | Histone proteins-Heterochromatin and Euchromatin |
| Heterochromatin | Not very active DNA |
| Euchromatin | DNA is more active & chromatin is dispersed |
| What is the Nucleolus? | Place where ribosomes are organized & synthesized. Most DNA stored here |
| What is the function of the Nucleus? | Replication of DNA to provide continuity of genetic info and Transcription of DNA to mRNA for protein synthesis |
| Endoplasmic reticulum | An organelle that is an interconnected network of tubules and contains the Rough Endoplasmic Reticulum (RER) and Smooth Endo. Ret. (SER) |
| Rough Endo. Reticulum | Ribosomes are attached and protein synthesis is carried out |
| Smooth Endo. Reticulum | NO ribosomes attached; No protein synthesis; Synthesis of lipids & steroids; Detox of some drugs; sequesters Ca ions in muscle cells |
| Golgi Apparatus | Stack of flatteneds sacs which process and package secreted proteins and integral membrane proteins, Lysosomal proteins (ex. postal service-sends everything on its way) |
| Lysosomes | Organelles that contain digestive enzymes; Resp. for breaking down or digesting material that has worn away or destined for disposal; Cellular recycling; Over 40 hydrolytic enymes that breakdown macromolecules; active in acidic environ. |
| Mitochondrion | Membrane-enclosed organelle where most of the energy of the cell is generated. Has 2 membranes inner/outer. Inner membrane contains proteins of elect. trans. system; Contains circular DNA and ribosomes |
| Peroxisomes | aka Microbodies; prevalent in kidney & liver cells; Contain catalase & peroxidases; Generate & breakdown hyrdo. peroxide into H20 and O2; also break down long chain fatty acids |
| Ribosomes | Site of protein synthesis; Composed of ribosomal protein and rRNA; Found in mitochondria, cytoplasm, and RER; found in both prokaryotic & eukaryotic cells |
| Cytoskeleton | Provides internal framework for cell; Provides for cellular mvmt. (internal-chromosomes during cell division, external-cilia & flagella); Provide binding sites for organelles; Controls vesicular traffic; Composed of microtubules, int. filaments, microfila |
| Microtubules | Biggest and hollow tubes; Composed of alpha & beta tubulin; form cilia & flagella; Functions incl. positioning of organelles; mvmt of cells; mvmt of organelles; changes in cell shape during embryogenesis |
| Microfilaments | Much thinner rod-like; Composed of actin; G-actin (unpolymerized), F-actin (polymerized) Function incl. muscle contraction, amoeboid mvmt of phagocytic cells, Cytoplasmic streaming, cleavage furrow during cell division |
| Intermediate Filaments | Intermediate in size; Fibrous; more diverse in composition than other skeletal elements; stable; provides mechanical strength |
