Basic Structure of a Cell
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Glossary - Cellbiology
1 Glossary - Cellbiology Blotting: (Blot Analysis) Widely used biochemical technique for detecting the presence of specific macromolecules (proteins, mRNAs, or DNA sequences) in a mixture. A sample first is separated on an agarose or polyacrylamide gel usually under denaturing conditions; the separated components are transferred (blotting) to a nitrocellulose sheet, which is exposed to a radiolabeled molecule that specifically binds to the macromolecule of interest, and then subjected to autoradiography. Northern B.: mRNAs are detected with a complementary DNA; Southern B.: DNA restriction fragments are detected with complementary nucleotide sequences; Western B.: Proteins are detected by specific antibodies. Cell: The fundamental unit of living organisms. Cells are bounded by a lipid-containing plasma membrane, containing the central nucleus, and the cytoplasm. Cells are generally capable of independent reproduction. More complex cells like Eukaryotes have various compartments (organelles) where special tasks essential for the survival of the cell take place. Cytoplasm: Viscous contents of a cell that are contained within the plasma membrane but, in eukaryotic cells, outside the nucleus. The part of the cytoplasm not contained in any organelle is called the Cytosol. Cytoskeleton: (Gk. ) Three dimensional network of fibrous elements, allowing precisely regulated movements of cell parts, transport organelles, and help to maintain a cell’s shape. • Actin filament: (Microfilaments) Ubiquitous eukaryotic cytoskeletal proteins (one end is attached to the cell-cortex) of two “twisted“ actin monomers; are important in the structural support and movement of cells. Each actin filament (F-actin) consists of two strands of globular subunits (G-Actin) wrapped around each other to form a polarized unit (high ionic cytoplasm lead to the formation of AF, whereas low ion-concentration disassembles AF). -
Bacterial Cell Membrane
BACTERIAL CELL MEMBRANE Dr. Rakesh Sharda Department of Veterinary Microbiology NDVSU College of Veterinary Sc. & A.H., MHOW CYTOPLASMIC MEMBRANE ➢The cytoplasmic membrane, also called a cell membrane or plasma membrane, is about 7 nanometers (nm; 1/1,000,000,000 m) thick. ➢It lies internal to the cell wall and encloses the cytoplasm of the bacterium. ➢It is the most dynamic structure of a prokaryotic cell. Structure of cell membrane ➢The structure of bacterial plasma membrane is that of unit membrane, i.e., a fluid phospholipid bilayer, composed of phospholipids (40%) and peripheral and integral proteins (60%) molecules. ➢The phospholipids of bacterial cell membranes do not contain sterols as in eukaryotes, but instead consist of saturated or monounsaturated fatty acids (rarely, polyunsaturated fatty acids). ➢Many bacteria contain sterol-like molecules called hopanoids. ➢The hopanoids most likely stabilize the bacterial cytoplasmic membrane. ➢The phospholipids are amphoteric molecules with a polar hydrophilic glycerol "head" attached via an ester bond to two non-polar hydrophobic fatty acid tails. ➢The phospholipid bilayer is arranged such that the polar ends of the molecules form the outermost and innermost surface of the membrane while the non-polar ends form the center of the membrane Fluid mosaic model ➢The plasma membrane contains proteins, sugars, and other lipids in addition to the phospholipids. ➢The model that describes the arrangement of these substances in lipid bilayer is called the fluid mosaic model ➢Dispersed within the bilayer are various structural and enzymatic proteins, which carry out most membrane functions. ➢Some membrane proteins are located and function on one side or another of the membrane (peripheral proteins). -
There Is Not a Latin Root Word Clear Your Desk Protist Quiz Grade Quiz
There is not a Latin Root Word Clear your desk Protist Quiz Grade Quiz Malaria Fever Wars Classification Kingdom Protista contains THREE main groups of organisms: 1. Protozoa: “animal-like protists” 2. Algae: “plant-like protists” 3. Slime & Water Molds: “fungus-like protists” Basics of Protozoa Unicellular Eukaryotic unlike bacteria 65, 000 different species Heterotrophic Free-living (move in aquatic environments) or Parasitic Habitats include oceans, rivers, ponds, soil, and other organisms. Protozoa Reproduction ALL protozoa can use asexual reproduction through binary fission or multiple fission FEW protozoa reproduce sexually through conjugation. Adaptation Special Protozoa Adaptations Eyespot: detects changes in the quantity/ quality of light, and physical/chemical changes in their environment Cyst: hardened external covering that protects protozoa in extreme environments. Basics of Algae: “Plant-like” protists. MOST unicellular; SOME multicellular. Make food by photosynthesis (“autotrophic prostists”). Were classified as plants, BUT… – Lack tissue differentiation- NO roots, stems, leaves, etc. – Reproduce differently Most algal cells have pyrenoids (organelles that make and store starch) Can use asexual or sexual reproduction. Algae Structure: Thallus: body portion; usually haploid Body Structure: 1) unicellular: single-celled; aquatic (Ex.phytoplankton, Chlamydomonas) 2) colonial: groups of coordinated cells; “division of labor” (Ex. Volvox) 3) filamentous: rod-shaped thallus; some anchor to ocean bottom (Ex. Spyrogyra) 4) multicellular: large, complex, leaflike thallus (Ex. Macrocystis- giant kelp) Basics of Fungus-like Protists: Slime Molds: Water Molds: Once classified as fungi Fungus-like; composed of Found in damp soil, branching filaments rotting logs, and other Commonly freshwater; decaying matter. some in soil; some Some white, most yellow parasites. -
Standard 2: CELL BIOLOGY – REVIEW of BASICS
Standard 2: CELL BIOLOGY – REVIEW OF BASICS CELL PART OR TYPE OF CELL WHERE FOUND WHAT DOES IT FUNCTION: MISCELLANEOUS ORGANELLE Prokaryotic cell Plant cell LOOK LIKE: Job it does in INFORMATION: things Eukaryotic cell Animal cell Describe or Draw the cell such as color, what it is Both Both made of, size, etc. plasma/cell See diagram Holds cell together Phospholipid bilayer with membrane both both Regulates what goes proteins in/out of cell Semipermeable cytoplasm both Clear thick jelly- Supports/protects both like material in cell cell organelles See diagram Control center nucleus eukaryotic both Contains DNA See diagram Where proteins are ribosome both both made See diagram Process proteins Golgi complex eukaryotic both that go to other /apparatus parts of cell Membrane-bound Digests materials lysosome eukaryotic animal sac of digestive within the cell enzymes Membrane-bound Stores water, food, One large one in plants vacuole eukaryotic both storage area waste and dissolved Many smaller ones in minerals animals endoplasmic Network of Transport materials Can be rough (with reticulum eukaryotic both membrane tubes throughout the cell ribosomes attached) or smooth (without ribosomes) See diagram Where cell respiration Called Powerhouse of cell mitochondria eukaryotic both occurs (releases Makes ATP from energy for cell to use) breaking down glucose See diagram Where photosynthesis Contains chlorophyll chloroplast eukaryotic plant takes place Converts light energy into chemical energy in glucose Some pro- and plant (also fungi Rigid structure -
Microorganisms – Protists: Euglena
Microorganisms – Protists: Euglena Euglena are unicellular organisms classified into the Kingdom Protista, and the Phylum Euglenophyta. All euglena have chloroplasts and can make their own food by photosynthesis. They are not completely autotrophic though, euglena can also absorb food from their environment. Euglena usually live in quiet ponds or puddles. Euglena move by a flagellum (plural flagella), which is a long whip-like structure that acts like a little motor. The flagellum is located on the anterior (front) end, and twirls in such a way as to pull the cell through the water. It is attached at an inward pocket called the reservoir. Color and label the reservoir grey. Color and label the flagellum black. The Euglena is unique in that it is both heterotrophic (must consume food) and autotrophic (can make its own food). Chloroplasts within the euglena trap sunlight that is used for photosynthesis and can be seen as several rod-like structures throughout the cell. Color and label the chloroplasts green. Euglena also have an eyespot at the anterior end that detects light, it can be seen near the reservoir. This helps the euglena find bright areas to gather sunlight to make their food. Color and label the eyespot red. Euglena can also gain nutrients by absorbing them across their cell membrane, hence they become heterotrophic when light is not available, and they cannot photosynthesize. The euglena has a stiff pellicle outside the cell membrane that helps it keep its shape, though the pellicle is somewhat flexible, and some euglena can be observed scrunching up and moving in an inchworm type fashion. -
Introduction to the Cell Cell History Cell Structures and Functions
Introduction to the cell cell history cell structures and functions CK-12 Foundation December 16, 2009 CK-12 Foundation is a non-profit organization with a mission to reduce the cost of textbook materials for the K-12 market both in the U.S. and worldwide. Using an open-content, web-based collaborative model termed the “FlexBook,” CK-12 intends to pioneer the generation and distribution of high quality educational content that will serve both as core text as well as provide an adaptive environment for learning. Copyright ©2009 CK-12 Foundation This work is licensed under the Creative Commons Attribution-Share Alike 3.0 United States License. To view a copy of this license, visit http://creativecommons.org/licenses/by-sa/3.0/us/ or send a letter to Creative Commons, 171 Second Street, Suite 300, San Francisco, California, 94105, USA. Contents 1 Cell structure and function dec 16 5 1.1 Lesson 3.1: Introduction to Cells .................................. 5 3 www.ck12.org www.ck12.org 4 Chapter 1 Cell structure and function dec 16 1.1 Lesson 3.1: Introduction to Cells Lesson Objectives • Identify the scientists that first observed cells. • Outline the importance of microscopes in the discovery of cells. • Summarize what the cell theory proposes. • Identify the limitations on cell size. • Identify the four parts common to all cells. • Compare prokaryotic and eukaryotic cells. Introduction Knowing the make up of cells and how cells work is necessary to all of the biological sciences. Learning about the similarities and differences between cell types is particularly important to the fields of cell biology and molecular biology. -
Can Protozoa Prove the Beginning of the World?
Southeastern University FireScholars Classical Conversations Spring 2020 Can Protozoa Prove the Beginning of the World? Karina L. Burton Southeastern University - Lakeland, [email protected] Follow this and additional works at: https://firescholars.seu.edu/ccplus Part of the Cell Biology Commons, and the Evolution Commons Recommended Citation Burton, Karina L., "Can Protozoa Prove the Beginning of the World?" (2020). Classical Conversations. 9. https://firescholars.seu.edu/ccplus/9 This Term Paper is brought to you for free and open access by FireScholars. It has been accepted for inclusion in Classical Conversations by an authorized administrator of FireScholars. For more information, please contact [email protected]. 1 Can Protozoa Prove the Beginning of the World? Karina L. Burton Classical Conversations: Challenge 4; Southeastern University ENGL 1233: English Composition II Grace Veach April 16, 2020 2 Abstract Protozoa are magnificent creatures. They exhibit all of the functions intrinsic to living organisms: irritability, metabolism, growth and reproduction. Within these functions, there are numerous examples of mutations that occur in order for organisms to adapt to their given environments. Irritability is demonstrated in protozoa by their use of pseudopodia, flagella, or cilia for motility; it has been shown that such locomotors exhibit diversity while maintaining similar protein and chemical structures that appear to be a result of evolutionary processes. Metabolism in protozoa is similar to that of larger animals, but their diet is unique. They primarily feast upon bacteria, which have begun mutating to evade easy ingestion and digestion by protozoa, therefore increasing their survival rate and making it necessary for protozoa to adapt. -
The Structure, Function, and Biosynthesis of Plant Cell Wall Pectic Polysaccharides
Carbohydrate Research 344 (2009) 1879–1900 Contents lists available at ScienceDirect Carbohydrate Research journal homepage: www.elsevier.com/locate/carres The structure, function, and biosynthesis of plant cell wall pectic polysaccharides Kerry Hosmer Caffall a, Debra Mohnen a,b,* a University of Georgia, Department of Biochemistry and Molecular Biology and Complex Carbohydrate Research Center, 315 Riverbend Road Athens, GA 30602, United States b DOE BioEnergy Science Center (BESC), 315 Riverbend Road Athens, GA 30602, United States article info abstract Article history: Plant cell walls consist of carbohydrate, protein, and aromatic compounds and are essential to the proper Received 18 November 2008 growth and development of plants. The carbohydrate components make up 90% of the primary wall, Received in revised form 4 May 2009 and are critical to wall function. There is a diversity of polysaccharides that make up the wall and that Accepted 6 May 2009 are classified as one of three types: cellulose, hemicellulose, or pectin. The pectins, which are most abun- Available online 2 June 2009 dant in the plant primary cell walls and the middle lamellae, are a class of molecules defined by the pres- ence of galacturonic acid. The pectic polysaccharides include the galacturonans (homogalacturonan, Keywords: substituted galacturonans, and RG-II) and rhamnogalacturonan-I. Galacturonans have a backbone that Cell wall polysaccharides consists of -1,4-linked galacturonic acid. The identification of glycosyltransferases involved in pectin Galacturonan a Glycosyltransferases synthesis is essential to the study of cell wall function in plant growth and development and for maxi- Homogalacturonan mizing the value and use of plant polysaccharides in industry and human health. -
Cell Structure and Function in the Bacteria and Archaea
4 Chapter Preview and Key Concepts 4.1 1.1 DiversityThe Beginnings among theof Microbiology Bacteria and Archaea 1.1. •The BacteriaThe are discovery classified of microorganismsinto several Cell Structure wasmajor dependent phyla. on observations made with 2. theThe microscope Archaea are currently classified into two 2. •major phyla.The emergence of experimental 4.2 Cellscience Shapes provided and Arrangements a means to test long held and Function beliefs and resolve controversies 3. Many bacterial cells have a rod, spherical, or 3. MicroInquiryspiral shape and1: Experimentation are organized into and a specific Scientificellular c arrangement. Inquiry in the Bacteria 4.31.2 AnMicroorganisms Overview to Bacterialand Disease and Transmission Archaeal 4.Cell • StructureEarly epidemiology studies suggested how diseases could be spread and 4. Bacterial and archaeal cells are organized at be controlled the cellular and molecular levels. 5. • Resistance to a disease can come and Archaea 4.4 External Cell Structures from exposure to and recovery from a mild 5.form Pili allowof (or cells a very to attach similar) to surfacesdisease or other cells. 1.3 The Classical Golden Age of Microbiology 6. Flagella provide motility. Our planet has always been in the “Age of Bacteria,” ever since the first 6. (1854-1914) 7. A glycocalyx protects against desiccation, fossils—bacteria of course—were entombed in rocks more than 3 billion 7. • The germ theory was based on the attaches cells to surfaces, and helps observations that different microorganisms years ago. On any possible, reasonable criterion, bacteria are—and always pathogens evade the immune system. have been—the dominant forms of life on Earth. -
Plant:Animal Cell Comparison
Comparing Plant And Animal Cells http://khanacademy.org/video?v=Hmwvj9X4GNY Plant Cells shape - most plant cells are squarish or rectangular in shape. amyloplast (starch storage organelle)- an organelle in some plant cells that stores starch. Amyloplasts are found in starchy plants like tubers and fruits. cell membrane - the thin layer of protein and fat that surrounds the cell, but is inside the cell wall. The cell membrane is semipermeable, allowing some substances to pass into the cell and blocking others. cell wall - a thick, rigid membrane that surrounds a plant cell. This layer of cellulose fiber gives the cell most of its support and structure. The cell wall also bonds with other cell walls to form the structure of the plant. chloroplast - an elongated or disc-shaped organelle containing chlorophyll. Photosynthesis (in which energy from sunlight is converted into chemical energy - food) takes place in the chloroplasts. chlorophyll - chlorophyll is a molecule that can use light energy from sunlight to turn water and carbon dioxide gas into glucose and oxygen (i.e. photosynthesis). Chlorophyll is green. cytoplasm - the jellylike material outside the cell nucleus in which the organelles are located. Golgi body - (or the golgi apparatus or golgi complex) a flattened, layered, sac-like organelle that looks like a stack of pancakes and is located near the nucleus. The golgi body modifies, processes and packages proteins, lipids and carbohydrates into membrane-bound vesicles for "export" from the cell. lysosome - vesicles containing digestive enzymes. Where the digestion of cell nutrients takes place. mitochondrion - spherical to rod-shaped organelles with a double membrane. -
Cell Life Cycle and Reproduction the Cell Cycle (Cell-Division Cycle), Is a Series of Events That Take Place in a Cell Leading to Its Division and Duplication
Cell Life Cycle and Reproduction The cell cycle (cell-division cycle), is a series of events that take place in a cell leading to its division and duplication. The main phases of the cell cycle are interphase, nuclear division, and cytokinesis. Cell division produces two daughter cells. In cells without a nucleus (prokaryotic), the cell cycle occurs via binary fission. Interphase Gap1(G1)- Cells increase in size. The G1checkpointcontrol mechanism ensures that everything is ready for DNA synthesis. Synthesis(S)- DNA replication occurs during this phase. DNA Replication The process in which DNA makes a duplicate copy of itself. Semiconservative Replication The process in which the DNA molecule uncoils and separates into two strands. Each original strand becomes a template on which a new strand is constructed, resulting in two DNA molecules identical to the original DNA molecule. Gap 2(G2)- The cell continues to grow. The G2checkpointcontrol mechanism ensures that everything is ready to enter the M (mitosis) phase and divide. Mitotic(M) refers to the division of the nucleus. Cell growth stops at this stage and cellular energy is focused on the orderly division into daughter cells. A checkpoint in the middle of mitosis (Metaphase Checkpoint) ensures that the cell is ready to complete cell division. The final event is cytokinesis, in which the cytoplasm divides and the single parent cell splits into two daughter cells. Reproduction Cellular reproduction is a process by which cells duplicate their contents and then divide to yield multiple cells with similar, if not duplicate, contents. Mitosis Mitosis- nuclear division resulting in the production of two somatic cells having the same genetic complement (genetically identical) as the original cell. -
Chapter 7 Cell Structure and Function, TE
Name______________________________ Class __________________ Date ______________ Chapter 7 Cell Structure and Function Section 7–1 Life Is Cellular (pages 169–172) This section explains what the cell theory is. It also describes the characteristics of two categories of cells, prokaryotes and eukaryotes. Introduction (page 169) 1. What is the structure that makes up every living thing? The cell The Cell Theory (pages 169–170) 2. What was Anton van Leeuwenhoek the first to see in the 1600s? He was the first person to see tiny living organisms in a drop of water. 3. What did a thin slice of cork seem like to Robert Hooke when he observed it through a microscope? The cork seemed to be made of tiny chambers. 4. What did the German botanist Matthias Schleiden conclude? He concluded that all plants are made of cells. 5. What did the German scientist Theodor Schwann conclude? He concluded that animals were also made of cells. 6. How did Rudolph Virchow summarize his years of work? He stated that where a cell exists, there must have been a preexisting cell. 7. What are the three concepts that make up the cell theory? a. All living things are composed of cells. b. Cells are the basic units of structure and function in living things. c. New cells are produced from existing cells. Basic Cell Structures (page 171) 8. Complete the table about structures that are common to most cells. COMMON CELL STRUCTURES Structure Description Cell membrane A thin, flexible barrier around the cell Cell wall A strong layer around the cell membrane in many cells © Pearson Education, Inc.