9 11 12 Chapter 5 Cells The working units of life Cell theory Schledien and Schwann Living things are made up of cells and cell products New cells formed by division of pre existing cells Fundamental similarities in chemical construction and metabolic activities of all cells The activity of the entire organism can be of its independent cell units Robert Hooke 1665 Cells in cork Crude light microscope 1000X Electron microscope more powerful than light 250 000X Transition electron microscope 2D Scanning electron microscope 3D Cell interior Complex Cell interior highly organized and highly complex Nucleoplasm stuff that is inside the nucleus Endoplasmic reticulum and ribosomes Complex system of membranes Creates fluid filled spaces inside Tubules elongated areas part of ER Expanded flattened sacks cisternae ER membrane contains a variety of enzymes 2nd part of ER secretion Rough ER Ribosomes Contains lots of ribosomes protein synthesis Composed of RNA and protein Can be free in ER or attached to ER Provide a site physical place for protein synthesis Golgi Bodies complex Processing and packaging proteins Biochemical reacting occurs on the ER System for transporting chemical substances Temporary storage of material Smooth ER No ribosomes detoxification steroid production calcium storage cellular Gamillo Golgi 1898 Highly developed in the cell Secrete materials out of the cell Secretory vesicles packages that are secreted out of the cell In golgi bodies proteins may be concentrated modified Lysosomes Carbs added Produced by Golgi bodies contain digestive enzymes Hydrolytic enzymes Lysosomes secrete enzyme on to bacteria WBC Digest foreign matter When cell dies it is digested by lysosomes Arthritis may be caused by a lysosome malfunction Mitochondria most Reactions of cellular respiration occur here Outer membrane Inner Membrane Cristae folds Matrix Thousands of mitochondria in a single active cell The membrane of the cristae contains enzymes These enzymes are very important to ATP production Cytochromes are also found in the membrane of the cristae These help to maximize the light gathering ability Chlorophyll Both mitochondria and chloroplasts contain DNA RNA and Ribosomes Plastids Plants and algae Food synthesis of storage Chloroplasts Thylakoid flattened sac Grana group of thylakoids They can divide independently of the cell Peroxisomes Organelle containing oxidative enzymes Utilize O2 for reactions Microtubules Hollow cylindrical structures Help to maintain cell shape Important in cilia and flagella structure Microfilaments Solid strings of protein molecules Important for cell structure and movement Amoeboid motion Cytoplasmic streaming plants cells Microtubules and microfilaments make up a framework for the cell This is referred to as a cytoskeleton Microtrabecular lattice grouping of organelles together System of microtubules microfilaments ER and mitochondria Contains contractile properties Acts similar to muscles System can cause redistribution and reorientation of internal components Causes localized contractions to occur The shape of the cell may change Centrioles become active when the process of cell division begins to occur Centrioles Function in cell division Each cell contains two centrioles Cilia and Flagella Flagella long whip like Cilia short many of them Involved in cell movement Similar structure Microtubules 9 2 arrangement 2 pairs in the center 9 pairs around the outside Vacuole Nucleus Bubble like space More common in plant cells Stores food salt pigments and wastes Control center of cellular processes Contains genes which determine the physical traits of an organism Coded into nucleic acids DNA Nuclear envelope surrounds nucleus Double membrane containing nuclear pores Chromosomes are found here Chromatin made up of DNA and protein DNA double stranded helix Strands are anti parallel and complementary 46 chromosomes Diploid 23 pairs 46 chromosomes Haploid 23 chromosomes Nucleolus Rich in RNA Responsible for making ribosomal RNA Contained inside the nucleus