Larry M. Frolich, Ph.D. Biology Department, Yavapai College Cells: Prokaryote and Eukaryotes Cells as fundamental living unitCells as fundamental living unit Prokaryotic and Eukaryotic CellsProkaryotic and Eukaryotic Cells Protein synthesis (quick overview)Protein synthesis (quick overview) Organelles and parts of a cellOrganelles and parts of a cell

Larry M. Frolich, Ph.D. Biology Department, Yavapai College Cells are the basic and fundamental unit of life The first life was cellular life The Molecules of Life are what cells and all their internal parts are made up of Cells are fundamental unit of life

Larry M. Frolich, Ph.D. Biology Department, Yavapai College Two types of cells Prokaryotic cells –Relatively Simple –Relatively Small –No organelles with Molecules of Life distributed throughout cytoplasm –Bacteria are all prokaryotic cells Eukaryotic cells –More complex –Much bigger (100 x size of prokaryotic cells) –Internally organized with membrane-bound organelles –Multi-cellular organisms, like plants and animals, are all made up of eukaryotic cells

Larry M. Frolich, Ph.D. Biology Department, Yavapai College Prokaryotic cells have: Cell membrane DNA molecule loose in cytoplasm Small Ribosomes where proteins are assembled from DNA information Microtubule structures like flagella and cilia Mitochondria and chloroplasts share most of these features, including their own independent DNA

Larry M. Frolich, Ph.D. Biology Department, Yavapai College WHAT EUKARYOTIC CELLS HAVE: Cell membrane Nucleus Mitochondria (and sometimes chloroplasts for photosynthesis) Larger ribosomes for protein assembly from DNA information Internal membranes that organize cellular spaces and distribution of Molecules of Life within cell (“cytoskeleton”) Eukaryotic cells (like our human cells) have:

Larry M. Frolich, Ph.D. Biology Department, Yavapai College Eukaryotic cell

Larry M. Frolich, Ph.D. Biology Department, Yavapai College WHAT CAN EUKARYOTIC CELLS DO? WHAT STRUCTURES ARE INVOLVED? Separate inside of cell from external environment and control what substances pass across membrane Cell Membrane Produce proteins/enzymes that catalyze chemical reactions or control movement across membrane Nucleus (DNA), Ribosomes on rough endoplasmic reticulum Break down sugars to form energy which is stored in phosphate bonds of ATP Mitochondria Organize distribution of Molecules of Life (macromolecules) and ions throughout cell Internal membrane system and “cytoskeleton” (ER, lysosomes, vessicles, microtubules) MoveFlagella, cilia, pseudopods

Larry M. Frolich, Ph.D. Biology Department, Yavapai College What structures are involved in protein synthesis? Nucleus Ribosomes Endomembrane system Protein synthesis

Larry M. Frolich, Ph.D. Biology Department, Yavapai College What is the structure and function of ribosomes? Organelles made of RNA and protein Found bound to the endoplasmic reticulum and free floating in the cell Site of protein synthesis Protein synthesis

Larry M. Frolich, Ph.D. Biology Department, Yavapai College Protein synthesis Remember that proteins control cell metabolism—how and where are they made, or synthesized in the cell?

Larry M. Frolich, Ph.D. Biology Department, Yavapai College What is the endomembrane system? A series of membranes in which molecules are transported in the cell It consists of the nuclear envelope, endoplasmic reticulum, Golgi apparatus, lysosomes and vesicles Protein synthesis

Larry M. Frolich, Ph.D. Biology Department, Yavapai College How does the endomembrane system function and appear? Protein synthesis

Larry M. Frolich, Ph.D. Biology Department, Yavapai College Summary of the parts of the endomembrane system? Rough endoplasmic reticulum – studded with ribosomes used to make proteins Smooth endoplasmic reticulum – lacks ribosomes but aids in making carbohydrates and lipids Golgi apparatus – flattened stacks that process, package and deliver proteins and lipids from the ER Lysosomes – membranous vesicles made by the Golgi that contain digestive enzymes Vesicles – small membranous sacs used for transport Protein synthesis

Larry M. Frolich, Ph.D. Biology Department, Yavapai College What are cilia and flagella? Both are made of microtubules Both are used in movement Cilia are about 20x shorter than flagella

Larry M. Frolich, Ph.D. Biology Department, Yavapai College What is the structure and function of the nucleus? Bound by a porous nuclear envelope Houses DNA and associated proteins called chromatin Contains nucleoplasm Nucleolus region(s) that contain ribosomal RNA (rRNA) Protein synthesis

Larry M. Frolich, Ph.D. Biology Department, Yavapai College What do mitochondria do and what do they look like? A highly folded organelle in eukaryotic cells Produces energy in the form of ATP They are thought to be derived from an engulfed prokaryotic cell

Larry M. Frolich, Ph.D. Biology Department, Yavapai College Endosymbiotic origin of mitochondria and chloroplasts Eukaryotic cells evolved from fusion or integration of prokaryotic cells Best evidence is in bacterial or prokaryotic appearance of mitochondria and chloroplasts These organelles are like little bacterial cells within our cells, now fully functionally integrated They perform fundamental cell functions. Mitochondria process sugars to produce energy; chloroplasts make sugars by photosynthesis But they maintain their own DNA and genetic control