Complete Biology Slides PDF

BIOLOGY 1 COMPLETED SLIDES GOOD LUCK!  BIOL 2101 General Biology I General Biology – BIOL 2101 – Sultan Qaboos University. Copy right© 2005 Pearson Education Inc. Publishing as Benjamin Cummings General Biology – BIOL 2101 – Sultan Qaboos Unive...

BIOLOGY 1 COMPLETED SLIDES GOOD LUCK!  BIOL 2101 General Biology I General Biology – BIOL 2101 – Sultan Qaboos University. Copy right© 2005 Pearson Education Inc. Publishing as Benjamin Cummings General Biology – BIOL 2101 – Sultan Qaboos University. Copy right© 2005 Pearson Education Inc. Publishing as Benjamin Cummings  Study Why study Biology? Life Interesting subject Diverse and rich field of study - Agricultural sciences - Environmental sciences - Medical sciences - Others (soil, marine, … etc) Bio-scientists observe organisms, ask questions and propose explanations General Biology – BIOL 2101 – Sultan Qaboos University. Copy right© 2005 Pearson Education Inc. Publishing as Benjamin Cummings  Monera Protista BIOL 2101 Units 1. Unifying themes in biology Fungi Plantae Animalia 2. Chemical basis of life 3. Cell, the basic units of life 4. Cell cycle and reproduction 5. Cellular energetics 6. Biotechnological and environmental applications of microorganisms General Biology – BIOL 2101 – Sultan Qaboos University. Copy right© 2005 Pearson Education Inc. Publishing as Benjamin Cummings  Unit 1.1: Features Common to all Organisms General Biology – BIOL 2101 – Sultan Qaboos University. Copy right© 2005 Pearson Education Inc. Publishing as Benjamin Cummings  This Lecture Outcomes - Recognize common features of life - Apply the concept of hierarchy in nature - Describe the concept of emergent properties in relation to hierarchy - Identify the cell as a basic unit of life - Compare the different types of cells General Biology – BIOL 2101 – Sultan Qaboos University. Copy right© 2005 Pearson Education Inc. Publishing as Benjamin Cummings  What are the properties of life? (b) Evolutionary (a) Order adaptation (c) Response to the environment (d) Regulation (g) Reproduction Figure 1.2 General Biology – BIOL 2101 – Sultan Qaboos University. Copy right© 2005 Pearson Education Inc. Publishing as Benjamin Cummings  Environmental Order adaptation Some properties of life General Biology – BIOL 2101 – Sultan Qaboos University. Copy right© 2005 Pearson Education Inc. Publishing as Benjamin Cummings  Response to the Regulation environment Some properties of life General Biology – BIOL 2101 – Sultan Qaboos University. Copy right© 2005 Pearson Education Inc. Publishing as Benjamin Cummings  Energy Growth and processing development Some properties of life General Biology – BIOL 2101 – Sultan Qaboos University. Copy right© 2005 Pearson Education Inc. Publishing as Benjamin Cummings Some properties of life Reproduction General Biology – BIOL 2101 – Sultan Qaboos University. Copy right© 2005 Pearson Education Inc. Publishing as Benjamin Cummings  Some properties of life (b) Evolutionary adaptation (a) Order (c) Response to the environment (e) Energy processing (d) Regulation (f) Growth and (g) Reproduction development Figure 1.2 General Biology – BIOL 2101 – Sultan Qaboos University. Copy right© 2005 Pearson Education Inc. Publishing as Benjamin Cummings  A hierarchy of organization Rule Hierarchy Sacred Hierarchy: a series or chain of ordered things or ranked subjects General Biology – BIOL 2101 – Sultan Qaboos University. Copy right© 2005 Pearson Education Inc. Publishing as Benjamin Cummings  A hierarchy of organization Life’s basic characteristic is a high degree of order – Based on a hierarchy of structural levels General Biology – BIOL 2101 – Sultan Qaboos University. Copy right© 2005 Pearson Education Inc. Publishing as Benjamin Cummings  Population Organism All individuals of a species in a specific area Community Organs systems All organisms in a particular ecosystem Organs Tissues Ecosystem Cells All living and nonliving Example things in a specific area Organelles Macromolecules Biosphere All environments Molecules on Earth General Biology – BIOL 2101 – Sultan Qaboos University. Copy right© 2005 Pearson Education Inc. Publishing as Benjamin Cummings  Extension through many levels Biosphere Ecosystems Communities Macroscopic Populations Individual Organisms Size and Complexity Organ Systems Multicellular Organs Based on a hierarchy of structural levels Tissues ✧Each level is building on the level Cells Unicellular Microscopic below it Organelles ✧Extends through many levels of Macromolecules biological organization Molecules Atoms General Biology – BIOL 2101 – Sultan Qaboos University. Copy right© 2005 Pearson Education Inc. Publishing as Benjamin Cummings  Emergent properties Due to increasing complexity ⮚ New properties emerge with each step upward in the hierarchy of biological order General Biology – BIOL 2101 – Sultan Qaboos University. Copy right© 2005 Pearson Education Inc. Publishing as Benjamin Cummings  Emergent properties Biological systems are much more than the sum of their parts - Example: a cell is much more than a bag of organelles General Biology – BIOL 2101 – Sultan Qaboos University. Copy right© 2005 Pearson Education Inc. Publishing as Benjamin Cummings  What is the basic unit of life? The cell is the lowest level of organization that can perform all activities required for life E.g. Cells divide (reproduction, growth, repair) General Biology – BIOL 2101 – Sultan Qaboos University. Copy right© 2005 Pearson Education Inc. Publishing as Benjamin Cummings  Two main types of cells No Ye s Prokaryotic Eukaryotic karyon : nucleus Prokaryotic cells Eukaryotic cells Bacteria and Archaebacteria Protists, fungi, plants and animals General Biology – BIOL 2101 – Sultan Qaboos University. Copy right© 2005 Pearson Education Inc. Publishing as Benjamin Cummings  Prokaryotes Eukaryotes No nucleus Have nuclei enclosed by a No membranous similar membrane Many membranous organelles organelles contain DNA DNA is not separated DNA is enclosed in from cytoplasm ribosomes nucleus Almost all have similar metabolic Some have cell walls pathways cell walls (e.g. plants) General Biology – BIOL 2101 – Sultan Qaboos University. Copy right© 2005 Pearson Education Inc. Publishing as Benjamin Cummings General Biology – BIOL 2101 – Sultan Qaboos University. Copy right© 2005 Pearson Education Inc. Publishing as Benjamin Cummings  Unit 1.2: Unity, diversity and classification of organisms General Biology – BIOL 2101 – Sultan Qaboos University. Copy right© 2005 Pearson Education Inc. Publishing as Benjamin Cummings  Unit 1.2: - Discuss the concepts of unity and diversity of organisms - Identify the concept of classification - List the different taxonomic levels - Define the term species - Apply binomial nomenclature - Recognize the different domains and kingdoms General Biology – BIOL 2101 – Sultan Qaboos University. Copy right© 2005 Pearson Education Inc. Publishing as Benjamin Cummings  Unity, diversity and classification of organisms Diversity and unity are the dual faces of life on Earth Diversity of life is seen through the high number of different organisms Plants and animals 2,000,000 to 4,500,000 Unity of life is seen by looking at the lower level of organization General Biology – BIOL 2101 – Sultan Qaboos University. Copy right© 2005 Pearson Education Inc. Publishing as Benjamin Cummings FUN FACT Obama coronatious Neopallia donaldtrumpi - Looks like Obamas ears -looks like trump hair SOME SPECIES HAVE INTERESTING NAMES  2- humped camel (Camelus bactrianus) 3- date palm (Phoenix dactylifera) 1- humped camel (Camelus dromedarius)  Fun fact One example out of the millions of interesting organisms in the world  Diversity General Biology – BIOL 2101 – Sultan Qaboos University. Copy right© 2005 Pearson Education Inc. Publishing as Benjamin Cummings  All are Unity made of cell(s) General Biology – BIOL 2101 – Sultan Qaboos University. Copy right© 2005 Pearson Education Inc. Publishing as Benjamin Cummings  Classifying Organisms Scientists categorize diverse items into a smaller number of groups. Taxonomy is the branch of biology that names and classifies species into a hierarchical order Example The hierarchy of biological classification has eight major taxonomic ranks which encompass all known life. Figure 1.14 General Biology – BIOL 2101 – Sultan Qaboos University. Copy right© 2005 Pearson Education Inc. Publishing as Benjamin Cummings How about a trick to help us remember biological classification ? Kids Keep Prefer Ponds Chocolat Clean e Over Or Fresh Frogs Green Get Salad Sick …or make up your own! General Biology – BIOL 2101 – Sultan Qaboos University. Copy right© 2005 Pearson Education Inc. Publishing as Benjamin Cummings  What is a species? Species is a Latin word meaning “kind” or “appearance”. Organisms with similar structural appearance are not necessarily from the same species Although humans can look different they are all one species General Biology – BIOL 2101 – Sultan Qaboos University. Copy right© 2005 Pearson Education Inc. Publishing as Benjamin Cummings  What is species? Species: individuals able to breed together and produce fertile offspring Based on fertility individual of species A + individual of species (e.g. cow ♀) (e.g. bull ♂) Fertile offspring of species A (Cows and bulls) General Biology – BIOL 2101 – Sultan Qaboos University. Copy right© 2005 Pearson Education Inc. Publishing as Benjamin Cummings  Biological nomenclature of organisms Binomial nomenclature - Carolus Linnaeus in the late 1800 - Each species has name of 2 parts ( 1^st part: Genus ,2^nd part: species) 1. Order Genus species Homo sapiens 2. Italic or underlined 3. Genus with capital letter and species with small letter General Biology – BIOL 2101 – Sultan Qaboos University. Copy right© 2005 Pearson Education Inc. Publishing as Benjamin Cummings  Domains & kingdoms of life 3 domains: 5 kingdoms: – Archaea Prokaryotic cells - Monera – Bacteria - Protista – Eukarya Eukaryotic cells - Fungi - Plantae - Animalia General Biology – BIOL 2101 – Sultan Qaboos University. Copy right© 2005 Pearson Education Inc. Publishing as Benjamin Cummings  The Kingdoms 1. Protista is primarily unicellular but includes the multicellular algae in many classification schemes. 1. Plants produce their own sugars and food by photosynthesis. 1. Fungi are decomposers that break down dead organisms and organic wastes. 1. Animals obtain food by ingesting other organisms. 1. Monera prokaryotic unicellular organisms. The kingdoms Plantae, Fungi, and Animalia are primarily multicellular. General Biology – BIOL 2101 – Sultan Qaboos University. Copy right© 2005 Pearson Education Inc. Publishing as Benjamin Cummings  Domains: higher than kingdoms Figure 1.15 General Biology – BIOL 2101 – Sultan Qaboos University. Copy right© 2005 Pearson Education Inc. Publishing as Benjamin Cummings  Unit 1.3: Prokaryotes Domain Archaea and Bacteria General Biology – BIOL 2101 – Sultan Qaboos University. Copy right© 2005 Pearson Education Inc. Publishing as Benjamin Cummings  Cellular organisms Bacteria Archaea Eukarya 5 Kingdoms Moner Protista Fung Planta Animali a i e a Prokaryotic cells Eukaryotic cells General Biology – BIOL 2101 – Sultan Qaboos University. Copy right© 2005 Pearson Education Inc. Publishing as Benjamin Cummings  This Lecture Outcomes - Recognize prokaryotic organisms - Distinguish the types of bacterial morphology - Differentiate gram positive and gram negative cells - Identity key structural components of bacterial cells - Define bacterial replication - Describe the importance of bacteria - Identify the categories of symbiotic relationships General Biology – BIOL 2101 – Sultan Qaboos University. Copy right© 2005 Pearson Education Inc. Publishing as Benjamin Cummings  What are prokaryotes? - single-celled organisms - no nucleus - lack other membrane- bound organelles have cell walls - microscopic General Biology – BIOL 2101 – Sultan Qaboos University. Copy right© 2005 Pearson Education Inc. Publishing as Benjamin Cummings  Where are prokaryotes found? Prokaryotes dominate the biosphere – Found wherever there is life – Some thrive in harsh habitats – what they lack in size they more than make up for in numbers Fig. 27.1 General Biology – BIOL 2101 – Sultan Qaboos University. Copy right© 2005 Pearson Education Inc. Publishing as Benjamin Cummings  Fun fact -how many prokaryotes do you think in this handful soil? -more than the number of people who ever lived  Prokaryotic diversity About 5,000 known species Estimation: 400,000 _ 4,000,000 species Two Domains Archaea Bacteria Halophiles Some canare Some cause salt beneficial diseases Methanogen Harmless Some are s methane harmful Pathogenic Thermophiles (Pathogenic) high temperature General Biology – BIOL 2101 – Sultan Qaboos University. Copy right© 2005 Pearson Education Inc. Publishing as Benjamin Cummings  How small are prokaryotes? Most prokaryotes have diameters of 1-5 µm - small compare to most eukaryotic(1-1ooµm) - some are large Figure 26.4 General Biology – BIOL 2101 – Sultan Qaboos University. Copy right© 2005 Pearson Education Inc. Publishing as Benjamin Cummings  How do we classify bacteria? 1 Cell Morphology Cell shape 2 1. Coccus (plural: Cocci ) -spherical 2. Bacillus (plural: Bacilli ) 3 -Rod-shaped 3. Spirillum (plural: Spirilla) -flagellated with a spirally twisted Rod-shaped form 4 4 Vibrio (plural: Vibrios) -curved bacteria General Biology – BIOL 2101 – Sultan Qaboos University. Copy right© 2005 Pearson Education Inc. Publishing as Benjamin Cummings  How do we classify bacteria? Cell Morphology Cell shape Cell arrangement 1. Diplococci -Two together 1. Streptococci -a chain 1. Staphlococci -irregular clusters General Biology – BIOL 2101 – Sultan Qaboos University. Copy right© 2005 Pearson Education Inc. Publishing as Benjamin Cummings  How do we classify bacteria? Cell Morphology Cell shape Cell arrangement Gram Staining Gram-negative Bacteria Gram-positive Bacteria General Biology – BIOL 2101 – Sultan Qaboos University. Copy right© 2005 Pearson Education Inc. Publishing as Benjamin Cummings  Why are some bacteria Gram-positive and some are Gram-negative? Gram-positive Gram-negative – have simpler cell walls – have complex cell walls – large amounts of – less peptidoglycans peptidoglycans – outer layer of – lipopolysaccharides (Fig. 27.5 p. 528) General Biology – BIOL 2101 – Sultan Qaboos University. Copy right© 2005 Pearson Education Inc. Publishing as Benjamin Cummings  Prokaryotic cell wall What is the main component of bacterial cell walls? -most bacterial cell walls contain peptidoglycan - peptidoglycan: polymer of modified sugars cross-linked by short polypeptides Why do bacteria need cell walls? – Maintain the cell shape – Provide physical protection – Prevent the cell from bursting General Biology – BIOL 2101 – Sultan Qaboos University. Copy right© 2005 Pearson Education Inc. Publishing as Benjamin Cummings  Prokaryotes Introduction to prokaryotes Prokaryotic classification – Cell morphology – Gram staining Shape Arrangement Bacterial structure – Cell wall – Genome – Flagella – Plasmid – Specialized membranes General Biology – BIOL 2101 – Sultan Qaboos University. Copy right© 2005 Pearson Education Inc. Publishing as Benjamin Cummings  Many prokaryotes are capable of taxis in heterogeneous environment Taxis: movement toward or away from a stimulus – Chemotaxis ✧ Positive chemotaxis ✧ Negative chemotaxis – Phototaxis – Thermotaxis – Barotaxis General Biology – BIOL 2101 – Sultan Qaboos University. Copy right© 2005 Pearson Education Inc. Publishing as Benjam  How can some bacteria move? Flagella – Mechanism of motility – Two or more helical filaments attached to a basal motor – Rotation of filaments move the prokaryotic cell like a corkscrew General Biology – BIOL 2101 – Sultan Qaboos University. Copy right© 2005 Pearson Education Inc. Publishing as Benjamin Cummings  How can prokaryotes perform their smetabolic function? - with specialized membranes Figure 27.8 General Biology – BIOL 2101 – Sultan Qaboos University. Copy right© 2005 Pearson Education Inc. Publishing as Benjamin Cummings  Prokaryotic genome Describe the Genophore or Bacterial chromosome - Smaller and simpler than eukaryotic cells - Single strand of circular DNA - Located in the nucleoid region (not nucleus) General Biology – BIOL 2101 – Sultan Qaboos University. Copy right© 2005 Pearson Education Inc. Publishing as Benjamin Cummings Prokaryotes may have smaller rings of DNA (plasmids) Extra-chromosomal DNA Consist of only a few genes – Resistance to antibiotics – Metabolism of unusual nutrients Capable of autonomous replication – Replicate independently of chromosome and can be transferred between partners during conjugation – Conjugation leads to increased genetic variation General Biology – BIOL 2101 – Sultan Qaboos University. Copy right© 2005 Pearson Education Inc. Publishing as Benjamin Cummings  Prokaryotes Introduction to prokaryotes Prokaryotic classification – Cell morphology – Gram staining Bacterial structure – Cell wall – Genome – Flagella – Plasmid – Specialized membranes Bacterial replication General Biology – BIOL 2101 – Sultan Qaboos University. Copy right© 2005 Pearson Education Inc. Publishing as Benjamin Cummings  How do prokaryotic cells reproduce? Prokaryotes reproduce only asexually via binary fission - Synthesizing DNA almost continuously Figure 12.10 General Biology – BIOL 2101 – Sultan Qaboos University. Copy right© 2005 Pearson Education Inc. Publishing as Benjamin Cummings A single cell in favorable conditions will produce a colony of offspring Colonies Figure 27.9 General Biology – BIOL 2101 – Sultan Qaboos University. Copy right© 2005 Pearson Education Inc. Publishing as Benjamin Cummings  Prokaryotes Introduction to prokaryotes Prokaryotic classification – Cell morphology – Gram staining Bacterial structure – Cell wall – Genome – Flagella – Plasmid – Specialized membranes Bacterial replication Importance of prokaryotes General Biology – BIOL 2101 – Sultan Qaboos University. Copy right© 2005 Pearson Education Inc. Publishing as Benjamin Cummings  Why are prokaryotes important? Many are beneficial – Intestinal bacteria produce important vitamins – Recycling of chemical elements in ecosystems Some cause serious illness (pathogenic bacteria) General Biology – BIOL 2101 – Sultan Qaboos University. Copy right© 2005 Pearson Education Inc. Publishing as Benjamin Cummings  Pathogenic bacteria Some pathogens are opportunistic – Travelers diarhoea caused by E. coli Some pathogens invade host tissues – TB caused by Mycobacterium tuberculosis General Biology – BIOL 2101 – Sultan Qaboos University. Copy right© 2005 Pearson Education Inc. Publishing as Benjamin Cummings  Pathogenic bacteria Some cause disease by producing toxins – Exotoxins: toxic proteins that produce specific symptoms even in the absence of the bacteria E.g. Travelers diarrhea caused by E. coli – Endotoxins : components of outer membranes of some Gram-negative bacteria responsible of fever and ache E.g. Food poisoning caused by Salmonella General Biology – BIOL 2101 – Sultan Qaboos University. Copy right© 2005 Pearson Education Inc. Publishing as Benjamin Cummings Why are prokaryotes important? Many are beneficial Some cause serious illness (pathogenic bacteria) Role in many symbiotic relationships – Interact with other species of prokaryotes or eukaryotes with complementary metabolisms Symbiont: smaller organism Host: larger organism General Biology – BIOL 2101 – Sultan Qaboos University. Copy right© 2005 Pearson Education Inc. Publishing as Benjamin Cummings Three categories of symbiotic relationships Commensalisms (Latin com mensa: sharing a table) – Symbiont receives benefits while host is not harmed or helped Many bacteria in the human body Mutualism: Vitamin producing intestinal – Both the symbiont and host bacteria benefit Parasitism – Symbiont (the parasite) benefits at the expense of host Mycobacterium tuberculosis General Biology – BIOL 2101 – Sultan Qaboos University. Copy right© 2005 Pearson Education Inc. Publishing as Benjamin Cummings  Prokaryotes Introduction to prokaryotes Prokaryotic classification – Cell morphology – Gram staining Bacterial structure – Cell wall – Genome – Flagella – Plasmid – Specialized membranes Bacterial replication Importance of prokaryotes – Beneficial bacteria – Pathogenic bacteria – Symbiotic bacteria General Biology – BIOL 2101 – Sultan Qaboos University. Copy right© 2005 Pearson Education Inc. Publishing as Benjamin Cummings  Unit 1.4: Eukaryotes Domain Eukarya General Biology – BIOL 2101 – Sultan Qaboos University. Copy right© 2005 Pearson Education Inc. Publishing as Benjamin Cummings  Cellular organisms Bacteria Archaea Eukarya Monera Protista Fungi Plantae Animalia Prokaryotic cells Eukaryotic cells General Biology – BIOL 2101 – Sultan Qaboos University. Copy right© 2005 Pearson Education Inc. Publishing as Benjamin Cummings  This Lecture Outcomes - Recognize the four different eukaryotic kingdoms - Classify Protista into subkingdoms and phyla - Relate and describe two key examples of Protista (Dinoflagellates and Apicomplexan) - Describe how fungi acquires its nutrients - Identify key structural components fungi - Define fungal reproduction - Describe the importance of fungi, focusing on three main examples (yeast, lichen, mycorrhizae) - Differentiate between plant and animal cells General Biology – BIOL 2101 – Sultan Qaboos University. Copy right© 2005 Pearson Education Inc. Publishing as Benjamin Cummings  Protista Many kingdoms – Neither plants, animals, nor fungi Protista defined partly by their structure – Most are Unicellular microscopic organisms E.g. Paramecium sp. – Simple multicellular organisms E.g. Slime mold – Complex multicellular organisms E.g. Seaweeds or kelps General Biology – BIOL 2101 – Sultan Qaboos University. Copy right© 2005 Pearson Education Inc. Publishing as Benjamin Cummings  Sub-kingdoms Protista Protozoa Slime molds Algae Animal-like Fungus-like Plant-like Amoebas Flagellates Ciliates Sporozoa Flagella Unicellular Multicellular Pseudopodia Cilia Non-motile 4 phyla Protista: a highly-diverse kingdom General Biology – BIOL 2101 – Sultan Qaboos University. Copy right© 2005 Pearson Education Inc. Publishing as Benjamin Cummings  Flagellates: Dinoflagellates whirling Flagellated protists Many have chloroplasts - Most are free-living - Mutualistic symbionts - Heterotrophic Some are bioluminescent General Biology – BIOL 2101 – Sultan Qaboos University. Copy right© 2005 Pearson Education Inc. Publishing as Benjamin Cummings  Ecological impact of Dinoflagellates Dinoflagellate blooms – Explosive growth – Aka red tides – Color comes from pigment in plastids Produce toxins – Kill many fish – Also deadly to humans Pollution of coastal Frequency of dinoflagellate blooms waters with fertilizers increased in the past decade, why? General Biology – BIOL 2101 – Sultan Qaboos University. Copy right© 2005 Pearson Education Inc. Publishing as Benjamin Cummings  Copyright © 2002 NASA General Biology – BIOL 2101 – Sultan Qaboos University. Copy right© 2005 Pearson Education Inc. Publishing as Benjamin Cummings  Sub-kingdoms Protista Protozoa Slime molds Algae Animal-like Fungus-like Plant-like Amoebas Flagellates Ciliates Sporozoa Flagella Unicellular Multicellular Pseudopodia Cilia Non-motile General Biology – BIOL 2101 – Sultan Qaboos University. Copy right© 2005 Pearson Education Inc. Publishing as Benjamin Cummings  Non-motile: Apicomplexans or Sporozoa All are parasites of animals and some cause serious human diseases – Plasmodium causes malaria Most apicomplexans have intricate life cycles - Life cycles both sexual and asexual stages - Often require two or more different host species General Biology – BIOL 2101 – Sultan Qaboos University. Copy right© 2005 Pearson Education Inc. Publishing as Benjamin Cummings  Plasmodium life cycle Copyright © CDC General Biology – BIOL 2101 – Sultan Qaboos University. Copy right© 2005 Pearson Education Inc. Publishing as Benjamin Cummings  Cellular organisms Bacteria Archaea Eukarya Monera Protista Fungi Plantae Animalia Prokaryotic cells Eukaryotic cells General Biology – BIOL 2101 – Sultan Qaboos University. Copy right© 2005 Pearson Education Inc. Publishing as Benjamin Cummings  Fungi – Nutritional mode Heterotrophs and acquire nutrients by absorption – Structural organization Distinctive structure; fungi are composed of hyphae – Growth and reproduction asexually or sexually – Importance General Biology – BIOL 2101 – Sultan Qaboos University. Copy right© 2005 Pearson Education Inc. Publishing as Benjamin Cummings  How do fungi acquire their nutrients? Heterotrophs – Acquire their nutrients by absorption Release Exoenzymes Hydrolytic ⮚ Powerful hydrolytic enzymes enzymes Digestion ⮚ Digest food outside body to simple molecules ⮚ Fungus can absorb and use Absorption General Biology – BIOL 2101 – Sultan Qaboos University. Copy right© 2005 Pearson Education Inc. Publishing as Benjamin Cummings  What is the structure of fungi? Most fungi are multicellular - With tiny filaments called hyphae - Hyphae form an interwoven mat called a mycelium Figure 31.2 General Biology – BIOL 2101 – Sultan Qaboos University. Copy right© 2005 Pearson Education Inc. Publishing as Benjamin Cummings  What are the two types of hyphae? Septate hyphae Coenocytic hyphae Figure 31.3 What are the cell walls of fungi made from? ⮚Cell walls of fungal hyphae are made of chitin General Biology – BIOL 2101 – Sultan Qaboos University. Copy right© 2005 Pearson Education Inc. Publishing as Benjamin Cummings  How do fungi reproduce? Most fungi release spores – produced either sexually or asexually – Trillions of spores can be produced at once Figure 31.3 /p. 619 General Biology – BIOL 2101 – Sultan Qaboos University. Copy right© 2005 Pearson Education Inc. Publishing as Benjamin Cummings  What are the key stages a of fungal sexual lifecycle? General Biology – BIOL 2101 – Sultan Qaboos University. Copy right© 2005 Pearson Education Inc. Publishing as Benjamin Cummings What are the key stages a of fungal sexual lifecycle? General Biology – BIOL 2101 – Sultan Qaboos University. Copy right© 2005 Pearson Education Inc. Publishing as Benjamin Cummings  Are all fungi multicellular? Yeast is an example of a unicellular fungi Reproduce sexually or asexually – Asexual reproduction by budding Figure 31.15 /p. 626 Importance: – Fermentation – Scientific research – Cause problems General Biology – BIOL 2101 – Sultan Qaboos University. Copy right© 2005 Pearson Education Inc. Publishing as Benjamin Cummings  Lichen Mutualistic association of fungi and a photosynthetic microorganism (e.g. algae or cyanobacteria) – Fungus minerals – Algae organic nutrients General Biology – BIOL 2101 – Sultan Qaboos University. Copy right© 2005 Pearson Education Inc. Publishing as Benjamin Cummings  Importance of lichen: – Important pioneers on newly cleared rock and soil surfaces – Nitrogen-fixing lichens add organic nitrogen to some ecosystems – Food for organisms in severe cold or desiccation ✧ Herds of caribou and reindeer – Lichens are particularly sensitive to air pollution General Biology – BIOL 2101 – Sultan Qaboos University. Copy right© 2005 Pearson Education Inc. Publishing as Benjamin Cummings  Mycorrhizae Mutualistic association of plant roots and fungi – Fungus Minerals from the soil for plant Organic nutrients – Plant General Biology – BIOL 2101 – Sultan Qaboos University. Copy right© 2005 Pearson Education Inc. Publishing as Benjamin Cummings  Ecological Role 1. Decomposers (saprobes) – Absorb nutrients from nonliving organisms 2. Parasites (of plants and humans) – Absorb nutrients from the cells of living hosts – Produce compounds that are harmful to humans ⮚ Aspergillus sp. produce aflatoxins (carcinogenic chemicals) 1. Mutualistic symbionts – Absorb nutrients from a host organism but, benefit their partner in some way 2G4eneral Biology – BIOL 2101 – Sultan Qaboos University. Copy right© 2005 Pearson Education Inc. Publishing as Benjamin Cummings  Commercial importance – Food ✧ Fruiting bodies of mushrooms – Preparation of other foods (e.g. flavoring) ✧ Bule cheeses Baking and winemaking - Production of antibiotics To treat bacterial disease The first antibiotic discovered was penicillin made by the common mold penicillium General Biology – BIOL 2101 – Sultan Qaboos University. Copy right© 2005 Pearson Education Inc. Publishing as Benjamin Cummings  Cellular organisms Bacteria Archaea Eukarya Monera Protista Fungi Plantae Animalia Prokaryotic cells Eukaryotic cells General Biology – BIOL 2101 – Sultan Qaboos University. Copy right© 2005 Pearson Education Inc. Publishing as Benjamin Cummings  Plantae - Land plants evolved from green algae - Primary producers - Autotrophs - Photosynthesis - Plants have diversified into roughly 290,000 living species Figure 29.1 2G7eneral Biology – BIOL 2101 – Sultan Qaboos University. Copy right© 2005 Pearson Education Inc. Publishing as Benjamin Cummings  Plant Cell Distinguishing features of plant cells: - Cell wall - Central vacuole - chloroplast Figure 7.7 & 7.8 /p.112 General Biology – BIOL 2101 – Sultan Qaboos University. Copy right© 2005 Pearson Education Inc. Publishing as Benjamin Cummings  Animalia Welcome to our kingdom – Multicellular, Eukaryotic – Move independently – Heterotrophic They digest food in an internal chamber – Lack rigid cell walls This differentiates them from Figure 32.1 plants and algae – Develop from embryonic layers General Biology – BIOL 2101 – Sultan Qaboos University. Copy right© 2005 Pearson Education Inc. Publishing as Benjamin Cummings  Animal Cell Distinguishing features of animal cells: - Lysosomes - Centrioles - flagella Figure 7.7 & 7.8 /p.112 General Biology – BIOL 2101 – Sultan Qaboos University. Copy right© 2005 Pearson Education Inc. Publishing as Benjamin Cummings  Unit 1.5: Biodiversity Conservation Biology General Biology – BIOL 2101 – Sultan Qaboos University. Copy right© 2005 Pearson Education Inc. Publishing as Benjamin Cummings  This Lecture Outcomes - Describe the importance of biodiversity - Recognize the importance of the three levels of biodiversity - Justify the existence of the biodiversity crisis - Identify the main threats to biodiversity - Relate biodiversity threats to the Omani environment - Describe the ways to conserve biodiversity General Biology – BIOL 2101 – Sultan Qaboos University. Copy right© 2005 Pearson Education Inc. Publishing as Benjamin Cummings  What is Biodiversity? The variety of different organisms in the world Each organism depends on the other and on the physical environment General Biology – BIOL 2101 – Sultan Qaboos University. Copy right© 2005 Pearson Education Inc. Publishing as Benjamin Cummings Why do we care about biodiversity? Human biophilia – Allows us to recognize the value of biodiversity for its own sake Practical benefits – Brings humans many practical benefits – E.g. many pharmaceuticals contain substances originally derived from Rosy periwinkle Figure 55.4 General Biology – BIOL 2101 – Sultan Qaboos University. Copy right© 2005 Pearson Education Inc. Publishing as Benjamin Cummings  There are Three Levels of Biodiversity Biodiversity has three main components -genetic diversity -species diversity -ecosystem diversity General Biology – BIOL 2101 – Sultan Qaboos University. Copy right© 2005 Pearson Education Inc. Publishing as Benjamin Cummings  Genetic Diversity Genetic variation within population Genetic variation between population – If a local population becomes extinct, then the entire population of that species has lost some genetic diversity General Biology – BIOL 2101 – Sultan Qaboos University. Copy right© 2005 Pearson Education Inc. Publishing as Benjamin Cummings  Species Diversity The variety of species in an ecosystem or throughout the biosphere Threatened Species that are likel to become endangered in the foreseeable future Endangered Species that is in danger of becoming extinct throughout its range Extinct Species that has no living member General Biology – BIOL 2101 – Sultan Qaboos University. Copy right© 2005 Pearson Education Inc. Publishing as Benjamin Cummings  Ecosystem Diversity Ecosystem diversity – Identifies the variety of ecosystems in the biosphere – Is being affected by human activity General Biology – BIOL 2101 – Sultan Qaboos University. Copy right© 2005 Pearson Education Inc. Publishing as Benjamin Cummings  Ecosystem Diversity Why is ecosystem diversity important? – Ecosystem services all the processes through which natural ecosystems and the species they contain help sustain human life on earth – Ecosystem services include Purification of air and water Detoxification and decomposition of wastes Cycling of nutrients Moderation of weather extremes And many others General Biology – BIOL 2101 – Sultan Qaboos University. Copy right© 2005 Pearson Education Inc. Publishing as Benjamin Cummings  How are ecosystem services affected by biodiversity loss?? Human Deforestation Use of pesticides Activities Reduce plant Reduce Reduce Insect and fungi Biodiversity species species reduce pollination, Reduce decomposition of wastes Ecosystem Services Reduce and cycling of nutrients purification of air General Biology – BIOL 2101 – Sultan Qaboos University. Copy right© 2005 Pearson Education Inc. Publishing as Benjamin Cummings  Three Levels of Biodiversity They are all connected Loss of Loss of Degradation of species specific genes Ecosystems Less Reduction in human genetic benefit diversity General Biology – BIOL 2101 – Sultan Qaboos University. Copy right© 2005 Pearson Education Inc. Publishing as Benjamin Cummings Do we have a biodiversity crisis? Yes!! The current rate of species extinction is high – Although it is difficult to determine the rate of species extinction under natural conditions – Globally, the rate of species loss may be as much as 1,000 times higher than at any time in the past 100,000 years General Biology – BIOL 2101 – Sultan Qaboos University. Copy right© 2005 Pearson Education Inc. Publishing as Benjamin Cummings  What is the biggest threat to biodiversity? Human activities – Are altering ecosystem processes on which we and other species depend Most species loss can be traced to four major threats 1-habitat destruction 2-introduced species 3-overexploitation 4-disruption of “interaction networks” General Biology – BIOL 2101 – Sultan Qaboos University. Copy right© 2005 Pearson Education Inc. Publishing as Benjamin Cummings  Habitat Destruction Human alteration of habitat – Is the single greatest threat to biodiversity throughout the biosphere General Biology – BIOL 2101 – Sultan Qaboos University. Copy right© 2005 Pearson Education Inc. Publishing as Benjamin Cummings  Habitat Destruction Massive destruction of habitat – Brought about by many types of human activity Agriculture Urban development Mining Pollution  Habitat Destruction Figure 55.5 Many natural landscapes have been broken up – Fragmenting habitats into small patches In almost all cases – Habitat fragmentation and destruction leads to loss of biodiversity General Biology – BIOL 2101 – Sultan Qaboos University. Copy right© 2005 Pearson Education Inc. Publishing as Benjamin Cummings  Introduced Species Introduced species – Are those that humans move from the species’ native locations to new geographic regions Introduced species that gain a foothold in a new habitat – Usually disrupt their adopted community Brown tree snake, Introduced kudzu introduced to Guam in cargo thriving in South Carolina Figure 55.6 (a,b) General Biology – BIOL 2101 – Sultan Qaboos University. Copy right© 2005 Pearson Education Inc. Publishing as Benjamin Cummings  Overexploitation Generally refers to the human harvesting of wild plants – At rates exceeding the ability of populations of those species to rebound – E.g. the fishing industry commercial hunting, over grassing Figure 55.7 General Biology – BIOL 2101 – Sultan Qaboos University. Copy right© 2005 Pearson Education Inc. Publishing as Benjamin Cummings  Ecosystem dynamics The extinction of one species can doom others General Biology – BIOL 2101 – Sultan Qaboos University. Copy right© 2005 Pearson Education Inc. Publishing as Benjamin Cummings  Threats to biodiversity in Oman Hunting – Most large mammals are now very rare because they were: ✧ Predators that threatened livestock (Arabian leopard and Arabian wolf) ✧ A food source (Arabian oryx, Arabian Tahr and Arabian gazelle). – All are now officially protected. Leopard Oryx Tah r General Biology – BIOL 2101 – Sultan Qaboos University. Copy right© 2005 Pearson Education Inc. Publishing as Benjamin Cummings  Threats to biodiversity in Oman Habitat destruction -large scale farming -large numbers of goats(and Dhofar, camels)selectively eating native plants -Urbanization -tourist resort development General Biology – BIOL 2101 – Sultan Qaboos University. Copy right© 2005 Pearson Education Inc. Publishing as Benjamin Cummings  How do we solve the biodiversity crisis? Understanding the organism at different levels – The organism itself (e.g. Genetics and Biochemistry) – How the organism interacts with other organisms – How the organism interacts with its physical environment Conservation biology: is the scientific study of nature and of Earth's biodiversity with the aim of protecting species, their habitats, and ecosystems. Restoration ecology: applies ecological principles – In an effort to return degraded ecosystems to conditions as similar as possible to their natural state General Biology – BIOL 2101 – Sultan Qaboos University. Copy right© 2005 Pearson Education Inc. Publishing as Benjamin Cummings  Unit 2.1: Chemical and physical properties of water General Biology – BIOL 2101 – Sultan Qaboos University. Copy right© 2005 Pearson Education Inc. Publishing as Benjamin Cummings  This Lecture Outcomes - Acknowledging water as a prerequisite for life - Describe chemical properties of water - Recognize the significance of physical properties of water for living things - Identify water as the solvent of life - Establish the effect of [H+] and [OH-] concentration on the pH of a solution - Recognize the importance of buffers in biological systems - Describe the causes and effects of acid precipitation General Biology – BIOL 2101 – Sultan Qaboos University. Copy right© 2005 Pearson Education Inc. Publishing as Benjamin Cummings Water  Water is the only common substance that exits in 3 forms in its natural environment The 3 states of water General Biology – BIOL 2101 – Sultan Qaboos University. Copy right© 2005 Pearson Education Inc. Publishing as Benjamin Cummings  Chemical properties of water - 2H-atom joined to O-atom through covalent bonds. O H - covalent bond: Inter-atomic linkage results from sharing an electron pair between two atoms. H General Biology – BIOL 2101 – Sultan Qaboos University. Copy right© 2005 Pearson Education Inc. Publishing as Benjamin Cummings  Chemical properties of water δ+ arranged in V-shaped O is more electronegative or H electron withdrawing - H2O is polar molecules δ − O H δ+ δ− Covalent Bond General Biology – BIOL 2101 – Sultan Qaboos University. Copy right© 2005 Pearson Education Inc. Publishing as Benjamin Cummings  Chemical properties of water Hydrogen bonds: a weak chemical bond between a slightly positive H-atom in one water molecule to a slightly negative O- atom of another molecule Figure 3.2 ✧ Determines most of physical properties of water. ✧ Plays great role in its chemical nature. General Biology – BIOL 2101 – Sultan Qaboos University. Copy right© 2005 Pearson Education Inc. Publishing as Benjamin Cummings  Physical properties of water Cohesion: binding together of similar molecules (H2O molecules) by hydrogen bonds - The force that holds a piece of matter together General Biology – BIOL 2101 – Sultan Qaboos University. Copy right© 2005 Pearson Education Inc. Publishing as Benjamin Cummings  Physical properties of water Adhesion: attraction between different kinds of molecules (H2O molecules and wall of plants vessel) General Biology – BIOL 2101 – Sultan Qaboos University. Copy right© 2005 Pearson Education Inc. Publishing as Benjamin Cummings Cohesion and Adhesion – Water that evaporates from a leaf is replaced by water from vessels in the leaf. – Hydrogen bonds cause water molecules leaving the veins to tug on molecules further down. cohesion – water also adheres to the wall of the vessels, helping it counter/resist the downward pull of gravity 1 General Biology – BIOL 2101 – Sultan Qaboos University. Copy right© 2005 Pearson Education Inc. Publishing as Benjamin Cummings 1  Surface tension: a property of liquid surface displayed by its acting as if it were a stretched elastic membrane - Measure of the force necessary to stretch or break a surface of a liquid - Related to cohesion ✧ Water has a high surface tension Figure 3.4 General Biology – BIOL 2101 – Sultan Qaboos University. Copy right© 2005 Pearson Education Inc. Publishing as Benjamin Cummings  Fun fact Did you know that how water freezes faster than cold water (Mpemba Effect).  Water is the solvent of life Solution: A completely homogeneous mixture of two or more substances. Solute (e.g. sugar) Solvent (e.g. water) Sugar solution General Biology – BIOL 2101 – Sultan Qaboos University. Copy right© 2005 Pearson Education Inc. Publishing as Benjamin Cummings  Aqueous solution: the solution in which water is the solvent - Water is not a universal solvent ✧ CANNOT dissolve all substances (e.g. oil) - Water is very versatile ✧ Because of the polarity of water molecules, they dissolve - Ionic solutes (e.g., NaCl) - Polar molecules (e.g., sugars) - Large molecules (e.g., proteins) General Biology – BIOL 2101 – Sultan Qaboos University. Copy right© 2005 Pearson Education Inc. Publishing as Benjamin Cummings  - Polar water molecule can interact with NaCl ✧ Formation of hydrogen bonds with Cl- and Na+ Negative oxygen regions – of polar water molecules are Na+ attracted to sodium cations (Na+). + – + + – – Positiv Na+ – e hydrogen + + regions of water – molecules Cl– Cl – + – cling to chloride anions (Cl–). + – + – – Figure 3.6 General Biology – BIOL 2101 – Sultan Qaboos University. Copy right© 2005 Pearson Education Inc. Publishing as Benjamin Cummings  Each dissolved ion is surrounded by a sphere of water molecules (hydration shell) ✧Hydration shell: the sphere of H2O molecules around each dissolved ion General Biology – BIOL 2101 – Sultan Qaboos University. Copy right© 2005 Pearson Education Inc. Publishing as Benjamin Cummings  ⮚Large molecules (e.g. proteins) can dissolve in water if they have enough ionic and polar regions Figure 3.7 General Biology – BIOL 2101 – Sultan Qaboos University. Copy right© 2005 Pearson Education Inc. Publishing as Benjamin Cummings  Substances Hydrophilic Hydrophobic Amphipathic Any substance Any substance having Any substance having affinity for aversion (strong dislike) having hydrophilic water for water and hydrophobic parts ⮚Ionic (NaCl) and ⮚Non-ionic and polar (sugars) non- polar (oils) ⮚Phospholipids, proteins ⮚Not completely ⮚The dominant bonds, C- dissolved (cotton) C and C-H, exhibit equal or near equal sharing of electrons. General Biology – BIOL 2101 – Sultan Qaboos University. Copy right© 2005 Pearson Education Inc. Publishing as Benjamin Cummings  Summary so far Living things have 70-95% H2O content Chemical properties of H2O: – Covalent bonds, polar molecule and hydrogen bonds Physical properties of H2O: – cohesion, adhesion and surface tension – Oceans & lakes do not freeze Water as a solvent – Aqueous solution (dissolves ionic, polar and large molecules) – Concentration General Biology – BIOL 2101 – Sultan Qaboos University. Copy right© 2005 Pearson Education Inc. Publishing as Benjamin Cummings  Dissociation of water Reversible reaction Water dissociates into hydronium ions and hydroxide ions Changes in the concentration of these ions can have a great affect on living organisms At equilibrium, [H+] = [OH-] =10-7M General Biology – BIOL 2101 – Sultan Qaboos University. Copy right© 2005 Pearson Education Inc. Publishing as Benjamin Cummings H+ and OH- are very reactive Low concentration, but H+ and OH- ions are very reactive – Slight changes in [H+] and OH-] can drastically affect the proteins and other molecules of a cell What substances could affect [H+] and [OH-]? - Acid - base The pH scale is used to describe how acidic or basic (the opposite of acidic) a solution is. 21 General Biology – BIOL 2101 – Sultan Qaboos University. Copy right© 2005 Pearson Education Inc. Publishing as Benjamin Cummings  Acid: a substance that increases [H+] of a solution ⮚ Example: hydrochloric acid (HCl) At equilibrium: [H+] = [OH-] =10-7M H2O H+ + OH- Adding HCl, HCl H+ + Cl- [H+] > [OH-]: acidic solution General Biology – BIOL 2101 – Sultan Qaboos University. Copy right© 2005 Pearson Education Inc. Publishing as Benjamin Cummings  Base: a substance that decreases [H+] of a solution ⮚ Example: Ammonia (NH3) At equilibrium: [H+] = [OH-] =10-7M H2O H+ + OH- + NH4 Adding NH3, NH3 + H + [H+] < [OH-]: basic solution General Biology – BIOL 2101 – Sultan Qaboos University. Copy right© 2005 Pearson Education Inc. Publishing as Benjamin Cummings  ⮚ Example: sodium hydroxide (NaOH) At equilibrium: [H+] = [OH-] =10-7M H2O H+ + OH- Adding NaOH, NaOH Na+ + OH- [H+] < [OH-]: basic solution General Biology – BIOL 2101 – Sultan Qaboos University. Copy right© 2005 Pearson Education Inc. Publishing as Benjamin Cummings  In any solution, the product of [H+] and [OH-] is constant and equals 10-14 [H+][OH-] =10-14 – In pure water, [H+][OH-] =10-14M Question: if [H+] = 10-3 M, what is [OH-]? [H+][OH-] =10-14 10-3[OH-] =10-14 [OH-] = 10-14-3 =10-11M 10 General Biology – BIOL 2101 – Sultan Qaboos University. Copy right© 2005 Pearson Education Inc. Publishing as Benjamin Cummings  pH scale The pH scale is used to describe how acidic or basic a solution is – pH scale: a measure of hydrogen ion concentration pH = - log[H+] – If we know the pH value, [H+] = 10-pH General Biology – BIOL 2101 – Sultan Qaboos University. Copy right© 2005 Pearson Education Inc. Publishing as Benjamin Cummings  Question: a solution has [OH_] = 10_9 M, what is pH? Is it acidic or basic solution? [H+] [OH_] =10_14 [H+] 10_9 =10_14 [H+] = 10_5M pH= - log[H+] pH= - log10_5 pH= -(-5) log10 = 5 (Solution is acidic) General Biology – BIOL 2101 – Sultan Qaboos University. Copy right© 2005 Pearson Education Inc. Publishing as Benjamin Cummings  pH is determined by relative [H+] – Low in acids (pH < 7) – High in bases (pH > 7) pH increases as [H+] decreases – pH represents tenfold difference in [H+] and [OH_] ✧A solution of pH 3 is not two times more acidic than a solution of pH 6 but 1000 times! ✧the base-10 logarithm function (pH= log10 [H+] ) is the inverse function of exponential function ([H+]= 10 pH) General Biology – BIOL 2101 – Sultan Qaboos University. Copy right© 2005 Pearson Education Inc. Publishing as Benjamin Cummings  Fun fact - Did you know that vegetables can act as pH indicator? Sensitivity of organisms to changes in pH Slight changes in pH and [OH_] huge change in [H+] – Affect organisms ✧ H+ and OH- are very reactive ✧ Affect proteins and complex molecules of cells Organisms control changes of pH in their cells – The internal pH of most living cells must remain close to pH 7 ✧ Use biological fluids (buffers) General Biology – BIOL 2101 – Sultan Qaboos University. Copy right© 2005 Pearson Education Inc. Publishing as Benjamin Cummings  Buffers Buffers: substances that resist changes to the pH of a solution when H+or OH_ is added to the solution – Accept H+ ions from the solution when they are in excess – Donate H+ ions when they have been depleted General Biology – BIOL 2101 – Sultan Qaboos University. Copy right© 2005 Pearson Education Inc. Publishing as Benjamin Cummings  Chemical nature of buffers ⮚Consist of an acid-base pair that reversibly combines with hydrogen ions ⮚ A weak acid and its corresponding base ✔Example: carbonic acid (H2CO3) Acid precipitation (acid rain) Natural or uncontaminated rain has a slightly acidic pH of 5.6. Why? ⮚ Due to formation of carbonic acid (H2CO3) Acid precipitation: refers to rain, snow or fog that is more acidic than pH 5.6 General Biology – BIOL 2101 – Sultan Qaboos University. Copy right© 2005 Pearson Education Inc. Publishing as Benjamin Cummings Causes of acid precipitation Burning of fossil fuels (coal, oil, and gas) produces: – Sulfur oxides (SOx) Examples: SO2, SO3 🡪 Sulfuric acid – Nitrogen oxides (NOx) Examples: NO2, NO3 🡪 Nitric acid General Biology – BIOL 2101 – Sultan Qaboos University. Copy right© 2005 Pearson Education Inc. Publishing as Benjamin Cummings Acid precipitation can damage life in Earth’s ecosystems Figure 3.9 General Biology – BIOL 2101 – Sultan Qaboos University. Copy right© 2005 Pearson Education Inc. Publishing as Benjamin Cummings Environmental effects of acid precipitation Impacts on forests and terrestrial life are more controversial Clear impacts on soils – Affect the solubility of soil minerals – Wash away key soil buffers and plant nutrients (calcium and magnesium) – Increase the solubility of compounds like aluminum to toxic levels General Biology – BIOL 2101 – Sultan Qaboos University. Copy right© 2005 Pearson Education Inc. Publishing as Benjamin Cummings  Summary Water dissociate into hydronium and hydroxide ions Acid: a substance that increases [H+] of a solution Base: a substance that decreases [H+] of a solution Acid precipitation can damage life in Earth’s ecosystems General Biology – BIOL 2101 – Sultan Qaboos University. Copy right© 2005 Pearson Education Inc. Publishing as Benjamin Cummings  Unit 2.2: Structure and function of macromolecules  This Lecture Outcomes - Distinguish the terms; matter, element, atoms and molecules - Identify organic compounds and describe their functional groups - List four major classes of macromolecules - Define condensation reactions and hydrolysis reactions  Organisms are composed of matter Matter: Anything that takes up space and has mass Element: a substance that cannot be broken down to other substances by chemical reactions - consist only of one kind of atoms – Example: C, H, O, N, Na, Cl,…etc 96% of living matter  Molecule: two or more atoms held together by covalent bonds ⮚ Example: O2, H2o,co2,NH3 amino acids ⮚ Is a single molecule ⮚ Made of 2 elements ⮚ Consists of 3 atoms  Organic compounds: chemical compounds build of carbon skeletons (chains or rings) – Along with C, they dominantly contain H, with or without O and N  Introduction Cells join smaller organic molecules together to form larger molecules. These larger molecules, macromolecules, may be composed of thousands of atoms and weigh over 100,000 daltons. The four major classes of macromolecules are: 1- CARBOHYDRATES 2- LIPIDS 3- PROTEINS 4- NUCLEIC ACIDS 6  Functional groups contribute to the molecular diversity of life The components of organic molecules that are most commonly involved in chemical reactions are known as functional groups. ❖ Functional groups are attachments that replace one or more hydrogen atoms to the carbon skeleton of the hydrocarbon. Each functional groups behaves consistently from one organic molecule to another. The number and arrangement of functional groups help give each molecule its Unique properties 7  Functional groups Functional groups: specific groups of atoms within molecules, that are attached to the carbon skeletons of organic molecule – Responsible for and/or involved for chemical reactions of those molecules – Useful as a basis for classification of large numbers of compounds according to their reactions - slight difference in functional group make great change C- skeleton  Functional groups most important to the chemistry of life Hydroxyl Carbonyl Carboxyl All are hydrophilic Amino Sulfhydryl Phosphate Increase solubility of organic compounds in water  Hydroxyl Hydrogen atom is bonded to oxygen atom (─OH) Compounds containing ─OH called alcohols and phenols  Carbonyl Carbon atom is joined to oxygen atom by a double bond (═CO) Compounds containing ═CO called: ⮚ Ketones (═CO within) ⮚ Aldehydes (═CO end)  Carboxyl Oxygen atom is double bonded to a carbon atom that is also joined to a hydroxyl group (─COOH) Compounds containing ─COOH called carboxylic acids or organic acids  Amino Nitrogen atom is bonded to two hydrogen atoms (─NH2) Compounds containing ─NH2 called amines  Sulfhydryl Sulfur atom is bonded to hydrogen atom (─SH) Compounds containing ─SH called thiols Phosphate  Large Macromolecules: large molecules composed of thousands of atoms – Complex in their structures – 4 major classes: ✧ Carbohydrates ✧ Proteins Form ✧ Nucleic acids polymers ✧ Lipids DO NOT form polymers  What is polymer? Polymer: chainlike molecule consists of many similar or identical building blocks (monomers) linked by covalent bonds - A polymer is made of monomers Polymers and their monomers Chemical mechanisms that build polymers Condensation reaction: a chemical reaction that connect monomers together via covalent bonds through loss of H2O molecules – Dehydration reaction or dehydration synthesis ✧One monomer provides a –OH group and the other provides a –H atom to form H2O  (Fig. 5.2a p.63) - Require energy and help of enzyme(catalysts)  Chemical mechanisms that break down polymers Hydrolysis of polymer: a chemical reaction in which a covalent bond of the polymer is broken by the addition of H2O molecule – One H2O molecule spilt into –OH group and –H atom, then one monomer receives –OH while the other receives –H (Fig. 5.2b p.63)  Types of bonds in polymers Covalent bonds result from condensation reactions – Glycosidic bond (di- and polysaccharides) – Ester bond (lipids) – Peptide bond (proteins or polypeptides) – Phosphodiester bond (Nucleic acid or polynucleotides)  Unit 2.3: Carbohydrates  This Lecture Outcomes - Classify carbohydrates into mono-,di- and polysaccharides - Describe the importance of monosaccharides, and their classification - Recognize that all monosaccharides are reducing agents - Describe the importance of disaccharides, and justify why some disaccharides are reducing agents - Differentiate between different polysaccharides and classify them into structural and energy storage macromolecules  Carbohydrates Chemical compounds that contain O, H, and C atoms, and no other element – Also called “watered carbon” Widespread organic substances in nature Essential constituents of all living things Formed from CO2 and H2O during photosynthesis  Include both sugars and their polymers Monosaccharides(simple sugars) Carbohydrates Disaccharides (double sugars) Polysaccharides (polymers)  One Monosaccharides sugar Single sugars or simple sugars The chemical formula: (CH2O)n Water-soluble, crystalline solids Some have a sweet taste Most names for sugars end in –ose  Examples of monosaccharides Name Chemical formula Glucose (dextrose) C6H12O6 Fructose (levulose) C6H12O6 Galactose (brain sugar) C6H12O6 Ribose C5H10O5  Monosaccharides: aldoses or ketoses Monosaccharides have a Aldose Ketose =CO (carbonyl) group and multiple –OH groups If the (=co) is at the end , the sugar is an aldose, if not, the sugars is a ketose  Because of =CO group, all monosaccharides are reducing sugars Act as reducing agents in alkaline solution – These sugars are oxidized Back Monosaccharides Classification (Fig. 5.3 p.64) Monosaccharides: linear or rings Roles of monosaccharides in life Glucose is the major fuel for cellular work Used for synthesis of sugar polymer and other molecules - example: amino, acids and fatty acids - Disaccharides and polysaccharides  Two Disaccharides Sugars Double sugars Sugar composed of two monosaccharides Water-soluble, crystalline solids Some have a sweet taste Names end in –ose  Examples of disaccharides Name Made of Found commonly in Maltose (malt sugar) 2 α-glucose molecules Barely-two Aldoses Sucrose (table sugar) Glucose + fructose Sugar cane and sorghum One Aldose + one Ketose Lactose (milk sugar) β-glucose and galactose Milk-two Aldoses Two monosaccharides are joined by glycosidic bond formed by condensation reaction (Fig. 5.5 p.65) 🖰  Boiling for 5 min. In alkaline solution, Sucrose Boiling for 5 min. Maltos Back e  Some disaccharides are reducing sugars due to the presence of free =CO group, while other are not!  Many Polysaccharides Sugars Polymers of simple sugars Many monosaccharides joined by glycosidic bonds formed by condensation reaction  Examples of polysaccharides Name Made of Found commonly in Starch α-glucose molecules Potatoes & grains Glycogen α-glucose molecules Livers and muscle cells Cellulose β-glucose molecules Fresh fruits, vegetables & grains Chitin β-glucose Exoskeleton of arthropods & cell molecules with N- wall of many fungi containing appendage What is the difference between α- glucose and β-glucose molecules?  Roles of polysaccharides in life Structural polysaccharides serve as building materials for the cell or whole organism - example: cellulose and chitin Storage polysaccharides serve as energy macromolecules that are hydrolyzed as needed - Example: starch and glycogen Cellulose Straight molecule (Fig. 5.8 p.73)  β-glucose with N- containing appendage Chitin Starch (Unbranched) (Branched) (α- glucose monomers) (Fig. 5.6a p.72)  Glycogen Extensively branched (α- glucose monomers) (Fig. 5.6b p.72)  Digestion of polysaccharides Almost all organisms have enzymes that can digest α- linkage - Starch and glycogen serves as energy storage α-glucose Vs β-glucose The enzymes that digest starch cannot hydrolyze the beta linkages in cellulose. – Cellulose in our food passes is not digested and passes out as “insoluble fiber”. – Cellulose stimulates the secretion of mucus. Some microbes can digest cellulose to its glucose monomers through the use of cellulase enzymes. Some fungi Bacteria in rumen of cow Microbes in termite gut  Did you know? Homeostatic control of blood glucose and diabetis – Blood glucose level 100 mg/ 100 ml blood – Role of insulin? (causes the liver to convert more glucose into glycogen and force about 2/3 of body cells (primarily muscle and fat tissue cells) to take up glucose from the blood) – Diabetes mellitus Type 1 –is caused by insufficient or non-existent production of insulin (inherited genetic condition). Type 2 - is due to a decreased response to insulin in the tissues of the body ( life style disease). Unit 2.4: Lipids  This Lecture Outcomes - Identify lipids as diverse hydrophobic molecules - Categorize the structure and function of key examples of lipids (fats, phospholipids and steroids)  Lipids Diverse hydrophobic molecules – Large biological molecules that do not include polymers (smaller than polymers) – Greasy to the touch and all have little or no affinity for water (insoluble in water) – Soluble in alcohol, ether, and other organic solvents – Examples: fats, oils, phospholipids, steroids, waxes and certain pigments  Fats or simple lipids Fats: Macromolecules constructed from two kind of smaller molecules : glycerol and fatty acids 🖰  Why fats are hydrophobic? (Fig. 5.10a & b p.69)  No C=C bond(s) – Saturated fatty acid – Solid at room temperature - Animal butter One or more C=C bond – Unsaturated fatty acid – Liquid at room temperature - Vegetable oils - Fish oil  Functions of fats in organisms Energy storage - 1 g of fat molecule stores more 2x as much energy as 1 g of polysaccharide molecule Serve to cushion vital organs (e.g. kidney) Provide a layer of insulation in some animals  Phospholipids -phospholipids are major components of cell membranes  Made of glycerol joined to 2 fatty acids and a OPO32- group – OPO3 attached to at the third position of the glycerol – OPO3 may be bonded to attachment like choline (Fig. 5.12a, b & c p.70)  Phospholipids and water The interaction of phospholipids with water is complex. WHY? – The fatty acid tails are hydrophobic – but the phosphate group and its attachments form a hydrophilic heat.  Phospholipids are amphiphilic molecules Addition of phospholipids in water form spherical aggregates called micelle (Fig. 5.13a p.70)  At the surface of a cell, phospholipids are arranged as a bilayer (Fig. 5.13b p.70)  Role of phospholipids The major component of cell membranes - The phospholipid bilayer forms a barrier between cell and the external environment  Steroids Lipids characterized by a C-skeleton consisting of 4-fused rings with different functional groups – Example: cholesterol – Different steroids are created by varying functional groups attached to the rings.  Roles of cholesterol – Component of animal cell membranes Precursor for synthesis of other steroids(e.g. sex hormones) Unit 2.5: Proteins  This Lecture Outcomes - Explain the structural constituents of polypeptides and how they are formed - Recognize the effect of polypeptide folding on protein conformation and consequently its function - Describe the four levels of protein structure - Identify some factors that affect a proteins conformation and result in loss of function - Classify the different types of proteins based on their functions  Protein Polypeptides: polymers of amino acids – Amino acid: organic molecule that made of 4 components attached to a central carbon (α carbon)c  Amino acids 20 different amino acids make up proteins Different in R groups or side chain ✧ R groups determines physical and chemical properties of each amino acid -polar amino acids -Non-polar amino acids -Electrically charged amino acids (Fig. 5.15 a& b p.72-73)  (Fig. 5.15 c p.73) Have functional groups that are charged (ionized) at cellular pH. -some R group are bases, other are acids.  Formation of polypeptides Peptide bond is formed by a condensation reaction which removes a –OH group from the C- terminus of one amino acid and a –H from the N-terminus of another amino acid  Polypeptide Repeating the process over and over creates a long polypeptide chain. Attached to the backbone are the various R groups. Polypeptides range in size from a few monomers to thousands. 8 Polypeptide chain function depends on its conformation Protein consists of one or more polypeptides folded and twisted into specific conformation – Conformation: three-dimensional (3D) shape or structure of macromolecule ✧ Determined by the sequence of amino acids in the polypeptide chain(s) 🖰  The ability of protein to recognize and bind to some other molecule depends on its conformation  Spontaneous Folding of polypeptide into a protein ✧ Responsible for the conformation of protein  Protein structure 4 levels of protein structure: -primary Organize the folding within a -secondary single polypeptide to form a protein -tertiary Structure arises when two or more - Quaternary polypeptides join to form a protein  Primary protein structure: sequence of amino acids covalently bonded with peptide bonds (Fig 5.18 p.75)  Secondary protein structure: results from hydrogen bonds at regular intervals along the polypeptide backbone β pleated sheet 🖰 O HH OHH OHH OHH Amino acid CCN R CCN R CC R CCN N CN CCN CCN CCN CC subunits R R R OHH R H OHH OHH O R R R R O C O C O C O H H C C CNHC H C NHCNHC NHCN N H HH H C H O C H C C O C O O N HC NH R R R R H R H C C N H O C H OC N H N H O C O CN α helix HCRHCR HCRH CR N HOC N H O C OC NH NH O C C C R R (Fig 5.20 p.76)  Tertiary protein structure: the overall three-dimensional shape of a polypeptide ⮚Results from a variety of interactions between R groups and the polypeptide backbone