Cell Structure and Function Lesson 6 PDF

Cell Structure and Function Lesson : 6 Biol 101  OBJECTIVES Know about Microscope and cell fractionation Differentiate between Eukaryotic and Prokaryotic cells Know about Cells organelles Know the types and functions of the cytoskeleton Know the Extrac...

Cell Structure and Function Lesson : 6 Biol 101  OBJECTIVES Know about Microscope and cell fractionation Differentiate between Eukaryotic and Prokaryotic cells Know about Cells organelles Know the types and functions of the cytoskeleton Know the Extracellular components and connections between cells 2  Microscope and Cell fractionation Biologists use microscopes and cell fractionation to study cell structure and function. Two types of microscopy used Light microscopy , and electron microscopy where Improvements in the magnification and resolution have catalyzed progress in the study of cell structure. Centrifuge technique or cell fractionation is the separation of organelles and other subcellular structures from one another at different speeds to obtain pellets enriched in particular cellular components Biol 101  The Cell The cell is the basic structural, functional and biological unit of all known living organisms. All cells have plasma membrane, cytoplasm, genetic information and ribosomes There are two types of cells Prokaryotic (bacteria, Archaea) and Eukaryotic cells (animal, plant, fungi, protist) Biol 101 Prokaryotic / Eukaryotic Cells Biol 101  Cell Organelles An organelle is a membrane-bounded structure found within the Cytosol and carrying out specific activities for the cell. Biol 101  Cell Organelles: Genetic Instructions 1)Nucleus The control center of the cell. Contains the DNA code for the cell coiled into Chromosomes. Contains nucleoli where ribosomal subunits are made 2)Ribosomes Are made in nucleoli Consist of ribosomal RNA (rRNA) and proteins Make Proteins. Each Ribosome has 2 subunits LARGE Ribosomal subunit and SMALL one. Some are free, but others are attached to the Endoplasmic Reticulum, producing the Rough Endoplasmic Reticulum (RER). Biol 101  Cell Organelles: Endomembrane System 1)Rough endoplasmic reticulum (RER) 2)Smooth endoplasmic reticulum (SER) Extensive network of Membrane Are made up of lipid membranes. bounded tubules and Sacks. Has no Ribosomes. SES is involved in: RER function: Lipid synthesis Help in synthesis of proteins Carbohydrate metabolism and other secretions that produced from Ribosomes Make cells membranes Add carbohydrate to protein to Calcium storage in muscles. make Glycoproteins Detoxification of drugs and poisons Produces new membrane Biol 101  Cell Organelles: Endomembrane System 3)Golgi Apparatus 4)Lysosomes Found in Animal Cells. It is a set of stacked membranes Contain Hydrolytic Enzymes. Golgi apparatus function: Function : Break down of : -Cell macromolecules and ingested Modify Proteins. substances (Phagocytosis) Modify Carbohydrates on proteins - Damaged organelles for recycling (Autophagy) and phospholipids. Synthesis of many Polysaccharides. 5)Vacuole Sorting of Golgi products, which are Are large membrane-bounded vesicle then released in vesicles. Function : Digestion, storage, waste deposal, water balance, cell growth and protection Biol 101  Cell Organelles: Powerhouses / Metabolism 1)Mitochondria 2)Chloroplast Is covered by double membrane Is covered by two membranes Function: Location of cellular respiration Function: starch storage, Photosynthesis (make ATP) 3) Peroxisome Is covered by single membrane Function : contains oxidative enzymes, alcohol detoxification, oxidation of fatty acids... Biol 101  Cytoskeleton The cytoskeleton is a complex network of interlinking filaments and tubules that extend throughout the cytoplasm helps in structural support, in motility and signal transmission. It contains 3 types: Microtubules (made of tubulin, for organelles movement) Intermediate filaments (like Keratin, for supporting cell’s shape) Microfilaments (made of actin, for muscle contraction) Biol 101  Extracellular Components Cell wall in plant: made of cellulose fibers embedded in other polysaccharides and proteins. Extracellular matrix (ECM) in animal: made of Glycoproteins Extracellular components are involved in support, adhesion, movement and regulation Biol 101  Connections between cells / Cell Junctions Cell junctions connect neighboring cells in plants and animals Plasmodesmata in plant Pass through adjoining cell walls. Tight junctions, desmosomes and gap junctions in animal Biol 101 Biol 101