Sci7 Cell Structure (1) PDF

1  a n d a r t s f a P n s o c ti o g s Fu n T h i n v i n g L i 2 Prepared by: Ms. Mary Angelique M. Mundin, LPT  Characteristics of Living Things 1. It has complex orga...

1  a n d a r t s f a P n s o c ti o g s Fu n T h i n v i n g L i 2 Prepared by: Ms. Mary Angelique M. Mundin, LPT  Characteristics of Living Things 1. It has complex organizational structure (from smallest to the last functional unit). 2. Metabolism, all organism has the ability to transform materials or substances into other chemical form to be utilized by its body up to the cellular level. 3. Responsiveness,having the ability of living organism to react or respond to certain stimuli. 3  Characteristics of Living Things 4. Growth, an organism is capable in increasing size and mass of its body as a result of metabolism. 5. Reproduction, a living organism is capable of producing the same offspring or organism as it is. 6. Evolution, the ability of organism to adapt to the changing environment. 4 Cell Structure (Plant Cell and Animal Cell) 5  Cell > “basic unit of life” > Smallest functional unit of an organism > Cella (word origin) means “small room” 6  Cell Size ▪ Most cells are relatively small because as size increases, volume increases much more rapidly. – longer diffusion time 7 Cell Sizes 8  Characteristics of a Cell 1. Reproduction is possible through cell division. 2. Utilization of enzymes. 3. Metabolism that facilitates building of cell components, converting energy and releasing of by-products or waste of the cell. 9  Characteristics of a Cell 4. Responsive to both external and internal stimuli such as change in pH or in temperature. 5. All cells are encapsulated by a membrane. 6. Cells are the building block of life. 10 Taxonomic Hierarchy (C. Linnaeus) Mnemonic: Dear King Philip Came Over For Green Spaghetti 11 12 Taxonomic Hierarchy (C. Linnaeus) 1. Species: group of population which is similar in form, shape, and reproductive features so that fertile siblings can be produced. 13 Taxonomic Hierarchy (C. Linnaeus) 2. Genus: a group of similar species. E.g. ePanthera (“Big Cats”): Tigr Lion Leopard Jaguar Panther) 14 Taxonomic Hierarchy (C. Linnaeus) 3. Family: a collection of similar group of genus. Eg. Felidae: Cat Lion 15 Taxonomic Hierarchy (C. Linnaeus) 4. Order: One or more than one similar families constitute order. Eg. Carnivora: (Felidae) Cat Lion 16 Taxonomic Hierarchy (C. Linnaeus) 5. Class: One or more than one order makes a class. Eg. Mammalia: Bats Rodents Kangaroos Humans Whales 17 Taxonomic Hierarchy (C. Linnaeus) 6. Phylum (Animals) / Division (Plants): collection of similar classes. 9 Phyla (major): Mollusca Porifera Cnidaria Platyhelminthes Nematoda Annelida Arthropoda Echinodermata Chordata 18 Taxonomic Hierarchy (C. Linnaeus) 6. Phylum (Animals) / Division (Plants): collection of similar classes. 5 Divisions (Main) Thallophyta. Bryophyta. Pteridophyta. Gymnosperms. Angiosperms. 19 Taxonomic Hierarchy (C. Linnaeus) 6. Phylum (Animals) / Division (Plants): collection of similar classes Eg. Eg. Chordata: Spermatophyta (Mammalia): (seeded plants): Bats Rodents Mango Kangaroos Orange Humans String beans Whales Okra 20 Taxonomic Hierarchy (C. Linnaeus) 7 Kingdom Classification 7. Kingdom:is a Archaebacteria. taxonomic rank that is Eubacteria. composed of smaller Protista. groups called phyla (or Chromista. division of plants) Fungi. Plantae. Animalia. 21 Taxonomic Hierarchy (C. Linnaeus) 8. Domain: the top most taxonomic category. 22  History of the Cell Robert Hooke (1665) - Examine a cork sample under his own microscope. cellula (Micrographia book) – little holes cell – the term coined by Robert Hooke 23 History of the Cell Antoine Van Leeuwenhoek - He created a microscope with much higher magnification. - Protists and bacteria – from the saliva of Leeuwenhoek’s mouth and focusing it under his own microscope 24  History of the Cell Robert Brown (1773-1858) - He was the first person to discover the nucleus (nuclei, pl.) of the cell by discovering pollen grain traveling in out of the “ovals” in the cells of orchids. 25  History of the Cell Matthias Schleiden (1804-1881) - discovered plant cells. 26  History of the Cell Theodore Schwann (1810-1882) - discovered animal cells. 27  History of the Cell Robert Remak (1815-1865) - “every cells arises from another cell”. 28  History of the Cell Rudolf Virchow (1821-1902) - drew a conclusions from “every cells arises from another cell” (Remak) to lay the groundwork for cellular pathology. 29  Three Postulates of “Cell Theory” All organisms are made up of one or more cells. Cell is the basic unit of life. All cells arise from pre-existing cell. (Omnis cellula e cellula) 30 Types of Cells and their Parts 31  and their - An organism may be either unicellular Parts or multicellular. 32  Types of Cells and their Parts unicellular organism - contains only one cell. e.g. 33  Types of Cells and their Parts multicellular organism – is made up of more than one cell. E.g. Animal and plant cells 34  Prokaryotic Cells prokaryotes – from the Greek words pro – meaning “before”, and karyon – meaning “kernel”, is a cell that has no nucleus. nucleoid – is an nucleoid cytoplasm irregularly shaped region within the cell of prokaryote that contains all or most of the genetic materials. Plasmid 35  Prokaryotic Cells plasmids – are small, double-strand DNA circular materials found outside the nucleoid - (advantages) antibiotic resistance nucleoid cytoplasm Plasmid 36  Prokaryotic Cells ribosomes – are small dense structures scattered all over the cytoplasm - they aid in protein synthesis nucleoid cytoplasm Plasmid 37  Prokaryotic Cells plasma membrane – the first one near the cytoplasm - also called “cell membrane” is a very thin bilayer made up of phospholipids. - functions: nucleoid cytoplasm - Selecting barrier - Separates cytoplasm from the surrounding environment Plasmid 38  Prokaryotic Cells cell wall – covers up the plasma membrane - gives structural support and protection to the prokaryotes nucleoid cytoplasm Plasmid 39  Prokaryotic Cells capsule – covering the cell wall - for protection, the presence of the capsules in most disease-causing bacteria prevents them from being eaten by our white blood cells. slime layer – capsule nucleoid cytoplasm of bacteria *some bacteria that does not have capsules generally does not cause diseases. Plasmid 40  Prokaryotic Cells pili – (singular: pilus) are small hair-like projections found mainly in Gram negative prokaryotes. - It allows the prokaryotes to attach to the cell surface sex pili – a specialize type of pili, which help the male donor transfer its nucleoid cytoplasm genetic materials to the female recipient by conjugation. Plasmid 41 42  Prokaryotic Cells flagellum – (flagella, pl.) of prokaryotes are long, whiplike appendages composed of many subunits of flagellin (a globular protein) Bacterial cell wall nucleoid cytoplasm Rotar y motor Flagelli Sheat n h Plasmid 43  Prokaryotic Cells flagellum – is responsible for movement *not all prokaryotes have flagellum. Eg. cocci Bacterial cell wall nucleoid cytoplasm Rotar y motor Flagelli Sheat n h Plasmid 44 Visualizing Cells 45 Prokaryotic nucleoid Cell cytoplasm Plasmid 46  Eukaryotic Cells ▪ From the Greek words eu- which means “true”, and karyon, which means “kernel” ▪ Is a cell that has a true nucleus bound by a nuclear membrane. 47 48 49  Nucleus - is where the genetic material is located Directs activities of the cell ▪Usually single, RBC none Nucleolus - region of intensive ribosomal RNA synthesis. ▪Surface of nucleus bound by two phospholipid bilayer membranes (nuclear membrane) –Nuclear pores – protein gatekeepers ▪Usually proteins going in and RNA going out. 50 51  - the genetic material is linear and double stranded. Histone – a protein where the strands coiled twice 52 Nucleus 53  Chromosomes ▪ A threadlike of nucleic acids and protein found in the nucleus ▪ Carry genetic information in the form of genes. 54  Endomembrane System ▪ Compartmentalizes cell, channeling passage of molecules through cell’s interior. – Endoplasmic reticulum ▪Rough ER - studded with ribosomes ▪Smooth ER - few ribosomes 55  Endoplasmic reticulum ▪ Largest internal membrane ▪ Composed of lipid bilayer ▪ Serves as system of channels from the nucleus ▪ Functions in storage and secretion ▪ Rough ER is “rough” because of associated ribosomes (sites of protein synthesis) ▪ Smooth ER - lack associated ribosomes – contained embedded enzymes, catalyze synthesis of carbohydrate and lipid molecules. 56  Endomembrane System Golgi apparatus – collection of Golgi bodies ▪collect, package, and distribute molecules synthesized at one location in the cell and utilized at another location. ▪Front - cis , Back – trans ▪Cisternae – stacked membrane folds 57  Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Cisterna e cis face Protein s trans face Transport Golgi vesicle apparatu s Protein Vesicle Migratin Fusion budding g of vesicle from rough transport with endoplasmi vesicle Golgi c apparatus Ribosom reticulum e 58  Endomembrane System ▪ Vesicles – Lysosomes - membrane-bound vesicles containing digestive enzymes – from Golgi – Microbodies - enzyme-bearing, membrane-enclosed vesicles. ▪“exocytosis” – is how materials leave a cell through a cell membrane ▪Enzyme breaks down to water and oxygen. 59  Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Cytoplasm Endoplasmi c Phagocytosis reticulum Food Golgi vesicle apparatu s Lysosomes Transport vesicle Old or Plasma Digestion of damaged membran phagocytized organelle e food Breakdown particles of old Extracellula or cells organelle r fluid 60  Ribosomes ▪ Ribosomes are RNA-protein complexes composed of two subunits that join and attach to messenger RNA. – site of protein synthesis – assembled in nucleoli 61  Organelles With DNA ▪ Mitochondria – bounded by exterior and interior membranes – interior partitioned by cristae 62  Mitochondria ▪ "Powerhouse of the cell" - cellular metabolism ▪ Structure- outer and inner membranes, cristae ▪ Have their own DNA 63  Chloroplasts ▪ Chloroplasts are larger and more complex than mitochondria. ▪ Grana – closed compartments of stacked membranes. ▪ Thylakoids – disc shaped structure – light capturing pigment. ▪ Stroma – fluid matrix 64  Organelles With DNA ▪ Chloroplasts – have enclosed internal compartments of stacked grana, containing thylakoids – found in photosynthetic organisms 65  Cytoskeleton ▪ Network of protein fibers supporting cell shape and anchoring organelles. – Actin filaments ▪cell movement Microtubules – Microtubules Intermediate ▪Hollow tubes filaments ▪Facilitate cell movement ▪Centrioles – barrel-shaped organelles occur in pairs – help assemble animal cell’s Actin microtubules. – Intermediate filaments ▪Stable - don’t break down 66 Cytoskeleton 67  Plant Cells ▪ Central vacuole – often found at the center of a plant and serves as storage facility for water and other materials. ▪Cell wall ⮚ Primary walls – laid down while cell is growing ⮚ Middle lamella – glues cells together ⮚ Secondary walls – inside the primary cell walls after growth 68 Plant Cell 69  Animal Cells ▪ Animal cells lack cell walls. – form extracellular matrix ▪provides support, strength, and resilience 70 71 72 The End 73 74