1ST Lecture- Intro, Chemical Basis of Life, The Cell PDF

CHAPTER 1: INTRODUCTION TO ZOOLOGY, CHEMICAL BASIS OF LIFE & THE CELL  ZOOLOGY Gr. zoo/zoon, animal : logos, to study  Forms, physiology, behavior and ecology  zoologists usually s...

CHAPTER 1: INTRODUCTION TO ZOOLOGY, CHEMICAL BASIS OF LIFE & THE CELL  ZOOLOGY Gr. zoo/zoon, animal : logos, to study  Forms, physiology, behavior and ecology  zoologists usually specialize in one or more of the sub disciplines of zoology GENERAL ZOOLOGY 9/4/2023 2 ZOOLOGY: EVOLUTIONARY PERSPECTIVE Sterna antillarum (the least tern) is an oceanic shoreline and riverine bird distributed in three major breeding populations across North America (East-coast, West-coast and Central) European little tern (Sternula albifrons) 1942- redesignated- 1976 Least terns are predators of small fish Males establish nesting colonies 5-7 m apart Both sexes cooperate in creating nests and in parental care Parents/Adults become aggressive as hatching time nears GENERAL ZOOLOGY 9/4/2023 4 ZOOLOGY: EVOLUTIONARY PERSPECTIVE GENERAL ZOOLOGY 9/4/2023 5 ZOOLOGY: EVOLUTIONARY PERSPECTIVE Philippine Eagle (Pithecophaga jefferyi) is a giant forest raptor endemic to the Philippines. They are geographically restricted to the islands of Luzon, Samar, Leyte and Mindanao. Philippine eagles are monogamous and they bond for life. ( Sexually mature after 5-7 years) Nest building and Aerial displays (mutual soaring, dive chase and mutual talon presentation) Long lived species Preys- flying lemurs, squirrels, snakes, civets, hornbill, bats and monkeys (tree dwelling species) GENERAL ZOOLOGY 9/4/2023 6 ZOOLOGY: EVOLUTIONARY PERSPECTIVE PHILIPPINE EAGLE LEAST TERN KINGDOM - Animalia KINGDOM - Animalia PHYLUM- Chordata PHYLUM- Chordata CLASS- Aves CLASS- Aves ORDER- Accipitriformes ORDER- Charadriiforme FAMILY- Accipitridae FAMILY-Laridae GENUS- Pithecophaga GENUS- Sternula SPECIES- Pithecophaga jefferyi SPECIES- Sterna antillarum GENERAL ZOOLOGY 9/4/2023 7  Like all organisms, animals are named and classified into a hierarchy of relatedness Carolus Linnaeus- binomial nomenclature The first part is the genus name, and the second part is the species epithet Above the genus level, organisms are grouped into families, orders, classes, phyla, kingdoms, and domains, based on a hierarchy of relatedness GENERAL ZOOLOGY 9/4/2023 8 GENERAL ZOOLOGY 9/4/2023 9 ZOOLOGY: AN EVOLUTIONARY PERSPECTIVE Organic evolution- change in the genetic makeup of populations of organisms over time > source of animal diversity and explains family relationships within animal groups 10 ZOOLOGY: AN EVOLUTIONARY PERSPECTIVE 11 ZOOLOGY: AN EVOLUTIONARY PERSPECTIVE 12 ZOOLOGY: AN EVOLUTIONARY PERSPECTIVE Groups of individuals are more closely related if they share more of their genetic material (DNA) with each other than with individuals in other groups. These evolutionary relationships are ultimately based on shared DNA, they are reflected in inherited morphological characteristics, and they are represented by groupings in the classification system 13 ZOOLOGY: AN ECOLOGICAL PERSPECTIVE Ecology (Gr. okios, house + logos, to study) is the study of the relationships between organisms and their environment 14 ZOOLOGY: AN ECOLOGICAL PERSPECTIVE Rhabdotorrhinus waldeni, Rufous-headed Hornbill Anthracoceros montani, Sulu Hornbill Endemic to Western Visayas (Guimaras, Negros Endemic to Sulu with remaining population in and Panay) Tawi Tawi Aprroximately 1,500-4,000 individuals remains In 2019 it was reported that only 27 mature (2008) individual hornbills are still believed to be alive in GENERAL ZOOLOGY the wild. 9/4/2023 15 ZOOLOGY: AN ECOLOGICAL PERSPECTIVE THREATS NATURAL ANTHROPOGENIC (INCREASED HUMAN POPULATION) HABITAT LOSS/DESTRUCTION DEFORESTATION OVEREXPLOITATION OVERCONSUMPTION GENERAL ZOOLOGY 9/4/2023 16 ZOOLOGY: AN ECOLOGICAL PERSPECTIVE THREATS NATURAL ANTHROPOGENIC (INCREASED HUMAN POPULATION) HABITAT LOSS/DESTRUCTION DEFORESTATION OVEREXPLOITATION OVERCONSUMPTION GENERAL ZOOLOGY 9/4/2023 17 CHEMICAL BASIS OF LIFE MAJOR BIOLOGICAL MACROMOLECULES/ ORGANIC COMPOUNDS & INORGANIC COMPOUNDS  CHEMICAL BASIS OF LIFE - Chemicals that compose the structure and functions of living organisms - If you take any biological system apart you will eventually end up at the chemical level GENERAL ZOOLOGY 9/4/2023 19  LET’S REVIEW! Atom- smallest particle of matter (made up of smaller sub atomic particles- protons, neutrons and electrons) Element- made up of atom, the most basic form of matter Compound – combination of two or more elements (can be held together by ionic or covalent bonds) GENERAL ZOOLOGY 9/4/2023 20 WATER - Is an inorganic compound Waters unique properties support life High specific heat: Specific heat is the amount of energy required to change the temperature of a substance. Water's high specific heat allows for the moderation of the Earth's climate and helps organisms regulate their body temperature more effectively. Cohesion: The intermolecular attraction between like molecules. Surface tension results from cohesion of water. GENERAL ZOOLOGY 9/4/2023 21 WATER - Adhesion: The intermolecular attraction between unlike molecules. Capillary action results from the adhesive properties of water and the molecules that make up plant cells. Water expands and floats as it freezes. Ice is less dense than water so it floats in water.Ice can insulate large bodies of water and prevent it from freezing. It is a universal solvent: It is able to dissolve a large number of different chemical compounds. This feature also enables water to carry solvent nutrients in runoff, infiltration, groundwater flow, and living organisms. This is because water is polar and can dissolve other polar molecules. GENERAL ZOOLOGY 9/4/2023 22 ORGANIC COMPOUNDS Carbon is uniquely suited to form biological macromolecules It forms covalent bonds with other carbon: Because carbon has 4 electrons it can form 4 covalent bonds with other atoms. This makes it the only atom that can be used to build the variety of molecules needed for complex life. Biological macromolecules include- carbohydrates (sugars), lipids (fats), proteins (including enzymes) and nucleic acids (DNA, RNA) GENERAL ZOOLOGY 9/4/2023 23 CARBOHYDRATES Most abundant organic compound in the biosphere compounds of carbon, hydrogen, and oxygen. These elements usually occur in the ratio of 1 C: 2 H: 1 O serves as a major source of energy and structural components for living organisms Carbohydrates are usually grouped into the following three classes: 1. monosaccharides, or simple sugars; 2. disaccharides, or double sugars; and 3. polysaccharides, or complex sugars. GENERAL ZOOLOGY 9/4/2023 24 CARBOHYDRATES- MONOSACCHARIDES Monomers or simple sugars Most basic form of carbohydrates, can be combined to form larger carbohydrates. Glucose, Fructose and Galactose GENERAL ZOOLOGY 9/4/2023 25 CARBOHYDRATES-DISACCHARIDES Composed of two simple sugars bonded together Lactose or milk sugar, sucrose and maltose GENERAL ZOOLOGY 9/4/2023 26 CARBOHYDRATES-POLYSACCHARIDES Composed of thousands of monomers of glucose or other simple sugars Starch, cellulose, chitin and glycogen GENERAL ZOOLOGY 9/4/2023 27 LIPIDS fats and fatlike substances Functions as energy storage, as components of membranes, insulation barriers, lipoproteins, waterproof coatings and chemical messengers Simple Lipids, Compound Lipid and Derived Lipids GENERAL ZOOLOGY 9/4/2023 28 LIPIDS- SIMPLE LIPIDS TRIGLYCERIDES/NEUTRAL OILS True fats Commonly found in adipose tissue, olive oil and lard Solid and semisolid (neutral fats) chiefly originates from animals while the liquid (neutral oil) originates from plants GENERAL ZOOLOGY 9/4/2023 29 LIPIDS- SIMPLE LIPIDS Saturated- animal triglycerides, higher melting point- all carbon atoms make single bonds to hydrogen – solid or semisolid Unsaturated- plant tryglycerides, lower melting point, higher proportion of unsaturated fatty acids- liquid at room temperature WAXES- found in the surfaces of leaves, fruits, feathers and animal fur, can repel water GENERAL ZOOLOGY 9/4/2023 30 LIPIDS- COMPOUND LIPIDS PHOSPHOLIPIDS Contains glycerol, fatty acids and phosphoric group (phosphate group) Hydrophilic phosphate head and a hydrophobic fatty acid tail Found in animal tissues, as a major component of cell membranes (lipid bilayer) GENERAL ZOOLOGY 9/4/2023 31 LIPIDS- COMPOUND LIPIDS SPHINGOLIPIDS Contains sphingosine as the backbone (amino alcohol) Sphingomyelin found in nervous tissue- roles in signal transmission GLYCOLIPIDS Lipids with carbohydrate attached to it Components of plasma membrane- serve as recognition sites for specific chemicals, maintain stability of the membrane, attach cells to each other for tissue formation GENERAL ZOOLOGY 9/4/2023 32 LIPIDS- DERIVED LIPIDS Terpenes Primary constituents of essential oils of plants and flowers, found in pigments, fat soluble vitamins Sterols Cholesterol, androgens and estrogens (sex hormones) Adrenal corticosteroids. Ergosterol (plants) Cellular structure, communication and metabolism GENERAL ZOOLOGY 9/4/2023 33 PROTEINS are large, complex molecules composed usually of hundreds to thousands of amino acids linked together in one or more chains Have many roles in cells and between cells, mediating and participating in several biological processes GENERAL ZOOLOGY 9/4/2023 34 PROTEINS- LEVEL OF ORGANIZATION Primary Structure Order of amino acids in a polypeptide strand Determines the overall structure and biological function of a protein Secondary Structure Local three-dimensional folding of the polypeptide chain in the protein Alpha-helix or beta pleated GENERAL ZOOLOGY sheet 9/4/2023 35 PROTEINS- LEVEL OF ORGANIZATION Tertiary Structure Three-dimensional folding of the entire polypeptide chain Quaternary Structure The fitting together of two or more polypeptide chains, forming a functional protein Ex. Keratin and hemoglobin GENERAL ZOOLOGY 9/4/2023 36 PROTEINS-MEDIATED BIOLOGICAL PROCESS Structural proteins & Transport proteins Most abundant protein found in the human body Forms cells parts Ex. Collagen- gives strength and support to tissues- skin and bone Regulatory proteins Controls numerous cell processes Ex, gene regulatory proteins GENERAL ZOOLOGY 9/4/2023 37 PROTEINS-MEDIATED BIOLOGICAL PROCESS Enzymes Facilitates many chemical reactions Ex. Amylase- helps change starches into sugars Lactase- Lactase breaks lactose into glucose and galactose. Hormones Chemical messengers Ex, estosterone, Progesterone, Estrogen, FSH GENERAL ZOOLOGY 9/4/2023 38 PROTEINS-MEDIATED BIOLOGICAL PROCESS Antibodies Immunoglobulins, highly specific proteins responsible for detecting a foreign substance or “antigen” Fluid balance Proteins exert oncotic pressure to capillary pores and through osmosis pulls fluid from interstitial spaces back to the intravascular space to prevent loss of fluid. Pulmonary edema and Ascites GENERAL ZOOLOGY 9/4/2023 39 NUCLEIC ACIDS Large organic molecules with the chief function of carrying the genetic information in the form of a code Made up of polymers of nucleotides Deoxyribonucleic acid (DNA) & Ribonucleic acid (RNA) GENERAL ZOOLOGY 9/4/2023 40 NUCLEIC ACIDS Nucleotide is made up of a nitrogenous base, pentose sugar and a phosphate group. Nitrogenous bases can be either purine or pyrimidine GENERAL ZOOLOGY 9/4/2023 41 NUCLEIC ACIDS GENERAL ZOOLOGY 9/4/2023 42 CELL: BASIC UNIT OF LIFE PROKARYOTES EUKARYOTES lack nuclei and other membrane-bound larger and more complex than prokaryotic cells organelles cells with a membrane-bound nucleus containing classified into two domains: Archaea and DNA (true nucleus) Eubacteria contain many other structures called organelles (“little organs”) that perform specific functions network of specialized structures called microfilaments and microtubules organized into the cytoskeleton, which gives shape to the cell and allows intracellular movement GENERAL ZOOLOGY 9/4/2023 43  THE ANIMAL CELL EUKARYOTIC CELLS 1. The plasma membrane is the outer boundary of the cell. It separates the internal metabolic events from the environment and allows them to proceed in organized, controlled ways 2. Cytoplasm (Gr. kytos, hollow vessel 1 plasm, fluid) is the portion of the cell outside the nucleus. The semifluid portion of the cytoplasm is called the cytosol. Suspended within the cytosol are the organelles. 3. The nucleus (pl., nuclei) is the cell control center. It contains the chromosomes and is separated from the cytoplasm by its own nuclear envelope. GENERAL ZOOLOGY 9/4/2023 44 THE ANIMAL CELL 45  THE ANIMAL CELL The outer bilayered boundary of the cell; composed of protein, cholesterol, and phospholipids Protection; regulation of material movement; cell-to-cell recognition GENERAL ZOOLOGY 9/4/2023 46 THE ANIMAL CELL Semifluid enclosed within plasma membrane; consists of fluid cytosol and cytomembrane system Dissolves substances; houses organelles and vesicles The cytomembrane (or endomembrane) system consists of well-defined structures, such as the endoplasmic reticulum, Golgi apparatus, vacuoles, and vesicles. (2) The fluid cytosol suspends the structures of the cytomembrane system and contains various dissolved molecules. 9/4/2023 47 THE ANIMAL CELL Spherical structure surrounded by a nuclear envelope; contains nucleolus and DNA Contains DNA that controls cell’s genetic program and metabolic activities It has two major functions: (1) It directs chemical reactions in cells by transcribing genetic information from DNA into RNA, which then translates this specific information into proteins (e.g., enzymes) that determine the cell’s specific activities (functions). (2) It stores genetic information and transfers this information during cell division from one cell to the next, and from one generation of organisms to the next. 9/4/2023 48 THE ANIMAL CELL non-membrane-bound structures that are the sites for protein synthesis Contains RNA and protein; some are free and some attach to ER 9/4/2023 49 THE ANIMAL CELL Organelle with double, folded membranes Converts energy into a form the cell can use are double-membrane bound organelles that are spherical to elongated in shape. A small space separates the outer membrane from the inner membrane. The cristae increase the surface area available for the chemical reactions that trap usable energy for the cell 9/4/2023 50 THE ANIMAL CELL Extensive membrane system extending throughout the cytoplasm from the plasma membrane to the nuclear envelope Storage and internal transport; rough ER is a site for attachment of ribosomes; smooth ER makes lipids 9/4/2023 51 THE ANIMAL CELL (named for Camillo Golgi, who discovered it in 1898) is a collection of membranes associated physically and functionally with the ER in the cytoplasm Stacks of disk-like membranes Sorts, packages, and routes cell’s synthesized products 9/4/2023 52 THE ANIMAL CELL 9/4/2023 53 PROTOZOANS AND METAZOANS a protozoan (Gr. proto, first 1 zoa, animal) is a complete organism in which all life activities are carried on within a single plasma membrane. Protozoans lack collagen and chitinous cell walls. Protozoa display unicellular (cytoplasmic) eukaryote organization Maintains homeostasis Reproduction 54 PROTOZOANS AND METAZOANS COMMON ANIMAL FEATURES Heterotrophs Eukaryotic Multicellular No cell wall, no chloroplasts Motile 55 PROTOZOANS AND METAZOANS PORIFERA Asymmetrical Pores—filter feeders Not motile (sessile) Three cell types: pinacocytes, mesenchyme cells, and choanocytes Central cavity, or a series of branching chambers, through which water circulates during filter feeding No tissues or organs Provide habitat for other animals (a) Verongia sp. (b) The elephant ear sponge (Agelas clathrodes) 56 ACTIVITY 5: PROTOZOANS AND METAZOANS 57 PROTOZOANS AND METAZOANS CNIDARIA Digestive cavity called a coelenteron Radial/Biradial symmetry Diploblastic, tissue-level organization Predators-feed on crustaceans Corals provide important habitat for fish Specialized cells, called cnidocytes, used in defense, feeding, and attachment 58 PROTOZOANS AND METAZOANS 59 PROTOZOANS AND METAZOANS PLATYHELMINTHES Usually flattened dorsoventrally, triploblastic, acoelomate, bilaterally symmetrical Cephalization- head and brain Acoelomate- no body cavity Incomplete digestive system (one opening) Some are parasites in digestive tract 60 PROTOZOANS AND METAZOANS NEMATODA Also called nematodes Complete digestive system-separate mouth and anus (2 openings) Decomposers, predators (bacteria, inverts) 61 PROTOZOANS AND METAZOANS ANNELIDA Body metameric, bilaterally symmetrical, and worm-like i.e. earthworms, leeches True coelom Sensitive to vibrations on ground-rain Prey for robins, shrews, jays, snakes Leeches have cornified knobs to break skin, anticoagulant and anesthetic 62 PROTOZOANS AND METAZOANS MOLLUSCA Bilateral symmetry Mantle that secretes a calcareous shell and covers the visceral mass i.e. snails, slugs, clams, mussels, scallops, oysters, octopus and squid Variety in form 63 PROTOZOANS AND METAZOANS ARTHROPODA Have bilateral symmetry Have a separate mouth and anus Have jointed body sections / appendages and have a hard exoskeleton (chitin) Metamorphosis often present; reduces competition between immature and adult stages Examples include insects, crustaceans, spiders, scorpions and centipedes 64 PROTOZOANS AND METAZOANS ECHINODERMATA Adults with pentaradial symmetry and larvae with bilateral symmetry Calcareous endoskeleton in the form of ossicles that arise from mesodermal tissue Water-vascular system composed of water- filled canals used in locomotion, attachment, and/or feeding i.e. sea stars = starfish, sea urchins Important predators 65 PROTOZOANS AND METAZOANS CHORDATA Bilaterally symmetrical, deuterostomate animals A unique combination of characteristics present at some stage in development: notochord, pharyngeal slits or pouches, dorsal tubular nerve cord, postanal tail, and an endostyle or thyroid gland Complete digestive tract Ventral, contractile blood vessel (heart) i.e. fish, sharks, amphibians, reptiles, birds, mammals Notochord, nerve cord, gill slits, tail 66 PROTOZOANS AND METAZOANS 67 PROTOZOANS AND METAZOANS 68 THANK YOU! ANY QUESTIONS? GENERAL ZOOLOGY 9/4/2023 69