1. Life Individual survival Reproduction
Take in, digest, eliminate nutrients
Recognize self from non-self
Recognize enemies
Repair damage
Reproduction
Survival of species
Gene transfer

2. US
Vertebrates
Invertebrates
Plants
Eukaryotes
Animals
Algae
Fungi
Protozoa
Single-celled
Archaea
Prokaryotes
Bacteria
UCA

3. Cell Functions Maintenance Perpetuation of self Specialized functions
Recovery of energy from nutrients
Storage of energy
Synthesis of correct proteins and other cell components
Perpetuation of self
DNA replication
Cell division
Specialized functions
e.g. muscle, blood, nerve cells, immune system

4. The molecules of life Nucleic acids (DNA, RNA) Proteins Carbohydrates
Lipids
Lipoproteins, glycoproteins, vitamins….

5. DNA RNA Protein DNA + DNA Genomics The Genome Translation
Protein synthesis
Transcription
DNA RNA Protein
The Proteome
Proteomics
DNA + DNA
DNA Replication
Cell division

6. Structural elements - cell walls, membranes Catalysts - enzymes
PROTEINS
Chains of amino acids
Structural elements - cell walls, membranes
Catalysts - enzymes
Communication - within cells, between cells
Cytokines
Signal transduction factors
Receptors
Vital for regulation of growth, cell division

7. Schematic metabolic cycle
Cellular components
Nucleic acids, Carbohydrates, Protein, Fat
Metabolic intermediates
Food
Carbohydrates, Fats, Glucose, Proteins
ADP + Pi
NADP+
NADPH
ATP
ATP
Work
TransportAssemblyMovementHeat
NAD+
NAD+
NADH
NADH
ADP + Pi
Wastes
CO2, H2O, lactic acid
The Metabolome - Metabolomics

8. Viruses 0.02-0.3 micrometers diameter
Genetic material: ss or ds DNA, RNA
Protein coat
Some enzymes
Lipid envelope – enveloped/non enveloped viruses
Nomenclature semi-systematic
Hepatitis A Virus, HAV
Need host cell for replication

9. The plasma membrane Lipid bilayer
Glycolipid
Glycoprotein
Av. Width
7.5 nm
(75 Å)
Sugar
Polar
Non-polar
(Lipid)
Protein

10. The Flu Virion Lipid bilayer envelope Hemagglutinin Matrix protein
Neuraminidase

11. Envelope: lipid bilayer membrane + glycoproteins, typically acquired from host cell membranes
Capsid (protein coat): multiple copies of 1 or more proteins in an array

12. Life-cycle of virus Particle, virion Infects host cell
Genetic material uses host’s replication apparatus to produce new viral components (capsid, core proteins, genetic material)
Components assemble into viral particles, exit host cell, sometimes lysing host cell

13. Each type of virus has its own specific host
Viruses that colonize bacteria are bacteriophage viruses (bacteriophages).

15. Viruses in the Environmment
Must be able to survive outside host cell
Non-enveloped viruses are more persistent than enveloped viruses
Lipid envelope more easily damaged, protein coat confers stability
Enteric viruses are almost all non-enveloped
Hepatitis A, poliovirus, noroviruses, rotaviruses
Transmitted by direct and indirect contact, fecally contaminated water, food, fomites and air.

16. Respiratory viruses, mostly enveloped
adenoviruses, coronaviruses, rhinoviruses, influenza viruses,
Transmitted by direct and indirect contact, air (aerosols) and fomites (some also by water and food).

17. Unicellular organisms
Bacteria - procaryotes
Protozoa
Algae eucaryotes
Fungi

18. Procaryotic Cell (left) and Eucaryotic Cell (right)

19. Procaryotes: Bacteria and Others
Unicellular organisms
Simple internal organization
Multiply by binary fission
Diameter ~ micrometer
Envelope: cytoplasmic membrane, cell wall & capsule (polysaccharide)
Some have appendages:
flagella: for locomotion
pili: attachment to other cells for genetic transfer; virus receptor site
Standard Linnean nomenclature: Genus species

20. Diverse bacteria
Gram positive Gram negative

21. More bacterial types Aerobes Anaerobes Facultative aerobes
Rods (bacilli)
Spherical (cocci)
Comma-shaped (vibrios)
Spiral (spirochetes)

22. Bacteria in the Environment
Some bacteria form spores:
highly resistant to physical and chemical agents and
very persistent in the environment

23. Pathogenic Bacteria
Pathogenic bacteria possess structures or chemical constituents that contribute to virulence properties
Outer cell membrane of Gram negative bacteria: endotoxin (fever producer)
Exotoxins
Pili: for attachment to cells and tissues
Invasins: to invade cells

24. Unicellular Eucaryotes:
More complex internal organization:
organelles: discrete nucleus, mitochondria
Wide range of sizes: 2 micrometers and larger

25. Protozoa
Unicellular; non-photosynthetic; flexible cell membrane; no cell wall; some are parasites, have complex life-cycles
Wide range of sizes and shapes; 2 micrometers to 2 mm
Disease-causing:
Amoebae: Entamoeba histolytica
Flagellates: Giardia lamblia
Ciliates: Balantidum coli
Sporozoans: Plasmodium vivax
Coccidians: Cryptosporidium parvum
Microsporidia: Cyclosopora cayetanensis

27. Cryptosporidium parvum oocysts: ~5 m diameter
Wet mount by differential interference contrast microscopy
Acid fast stain of fecal preparation

28. Giardia lamblia cyst: ~10 x 8 micrometers

29. More Protozoans: Fungi
Fungi (yeasts and molds):
non-photosynthetic
immotile;
rigid cell wall
Molds:
grow as branched, interlacing chains or filaments (hyphae) called mycelia
Yeasts:
do not form mycelia
grow as single cells that bud
sexual reproduction possible
Mitospores (conidia) of Penicillium, one of the asexual Ascomycota
Yeasts

30. Algae Photosynthetic Rigid cell wall
Simple plants, protists, protozoa, plancton, derived from cyanobacteria ?
Wide range of sizes and shapes
2 micrometers and larger
Some algae are harmful
Algal booms
Toxins
Anabaena, anatoxins
Nostoc

31. Helminths (Worms) Multicellular animals
Some are human and/or animal parasites
Eggs pass via human and animal excreta to water, food, soil.
Several major groups:
Roundworms, Nematodes eg. Ascaris, Trichinella spiralis, hookworms
Flatworms Platyhelminthes: Cestodes (tapeworms): pork, beef tapeworms, and Trematodes (flukes) eg Schistosomes
Annelids (leeches)
Necator (hookworm)
eggs
adult

32. Infective stage: larvae
Eggs hatch in soil
Infective stage: larvae
Penetrate skin, migrate to blood, lungs, trachea
or are ingested
Adults mature in intestine
Attach to intestinal walls
anemia
Necator americanus , Ancylostoma duodenale (hookworm)

33. Trematodes
Schistosomes (blood flukes)
Liver fluke

34. Cestodes Head (scolex) attaches to tissue Grows in intestine
beef tapeworm, Taenia saginata
pork tapeworm (T. solium)
Grows in intestine

35. Multicellular organisms
Plants
Animals
Invertebrates
Vertebrates