The Basic Organization of Living Forms

1. The Basic Organization of Living Forms ESC 556 Environmental Biology Week 2

2. Fundamentals of Life • Characteristics of Life • Living matter vs. Inanimate matter • Cellular organisation • Nutrition • Growth • Respiration • Responsiveness • Movement • Excretion • Reproduction • Catabolism vs. Anabolism

3. The Flame of Life • Analogies • Respire • Nutrition • Reproduce • Excrete • Grows • Moves • Responsiveness • Organized • Differences • DNA/RNA • Anabolic Metabolism

4. The Cell • Smallest Unit of Life • prokaryotic vs. eukaryotic cells • Membrane bound nucleus • Organelles • Size differences • Surface Area / Volume Ratio

5. Prokaryotes vs. Eukaryotes Differences: • Eukaryotes have a nucleus and membrane bound organelles • Genetic material transfer

6. Cell Membrane • Separate the cell from its environment • Lipid bilayer w/ proteins • Attachment • Movement of water & other bulk items • Transport of molecules & ions • Reception of chemical messages • Passive transport • Diffusion, Osmosis, Facilitative diffusion • Active transport (pumps) • Endocytosis • Phagocytosis, pinocytosis

7. Endocytosis

8. Plant Cell Walls • Cellulose • Hemicelluloses • Pectin • Lignin • Organic material • Highest in high latititudes

9. Plant Cell Wall

10. Energy Transformations • Growth, maintenance and replication • 1st & 2nd Laws of Thermodynamic • Photosynthesis • Enzymes • ATP (Adenine triphosphate)

11. Photosynthesis & Respiration • 3 Bya: Capture photons and synthesize organic molecules • 2 – 1.5 Bya: Release Oxygen • Respiration • Formula: 6CO2 +12H2O + Light  6O2 + C6H12O6 + 6H2O • Chlorophyll • Chloroplast • Inefficient

12. Photosynthesis

13. Enzymes

14. Materials of Life • 97 % N, O, C, H • 90 & H and O  Water • Macromolecules • Carbohydrates • Lipids • Proteins • Nucleic Acids

15. Water • ¾ of the earth’s surface • 2/3 of all organisms • Three forms • Polar molecule • Universal solvent • Adhesion – transport systems • Stable against temperature changes – high heat of vaporization • Most dense @ 4oC

16. Carbohydrates • Small molecules to long polymers • Energy storage • Sugars (CH2O)n • Short term • Monosaccharides • Isomers • Long Term • Disaccharides & Polysaccharides • Polysaccharide Glucose

17. Carbohydrates • Structural Elements • Polysaccharide cellulose • Polysaccharide chitin • Cellulases

18. Lipids • Non-polar • Many different kinds • Fats • Storage of energy • Phospholipids • Cell membrane • Polar + non-polar groups : Lipid bilayer • Terpenes • Steroids

19. Proteins • Various functions • Fibres, enzymes, hormones, transport, ion-binding, toxins • Chain of amino acid subunits (polypeptide) • 20 amino acids

20. Nucleic Acids • Information storage • Deoxyribonucleic acid (DNA) & Ribonucleic acid (RNA) • DNA • Replicate itself • Pass on hereditary material • Nucleotides • DNA structure • Sugar-phosphate backbone • Four bases

21. Nucleic Acids • DNA structure

22. Nucleic Acids/DNA

23. Nucleic Acids • RNA • Read the DNA & produce proteins • Structure • Ribose • Uracil instead of thymine

24. From DNA - Proteins

25. Genetic Code

26. The Diversity of Life • At least 10 million species • 1.5 million described

27. Levels of Organization • Individual • Unitary vs. Modular • Population • Defined area • Community • Physical feature of the habitat or dominant species • Ecosystem • Interaction between communities & their environment • Material recycling

28. Species concept • Species • Morphological species concept • identical by morphological (anatomical) criteria • Biological species concept • groups of potentially or actually interbreeding natural populations that are reproductively isolated from other such groups • Isolating mechanisms • Habitat, seasonal, behavioral, mechanical, gamete, hybrid failure • Problems with fossil & asexual species • Hybrid problem • Evolutionary/Phylogenetic species concept • All those individuals that share a common evolutionary history

29. Phylogenetic relationships

30. Evolutionary/Phylogenetic species

31. Classification & the Binomial System • Linnaeus • Felis catus • Ranks

32. Ranks / Taxonomic Hierarchy Domain Kingdom Phylum Class Order Family Genus Species Eukarya Animalia Chordata Mammalia Carnivora Felidae Felis catus

33. Three Domains • Bacteria • Archaea • Eukarya prokaryotes eukaryotes

34. Bacteria vs. Archaea • Peptidoglycan layer

35. Six Kingdoms • Eubacteria • Archaeabacteria • Animalia • Plantae • Fungi • Protista prokaryotes eukaryotes

36. Six Kingdoms • Eubacteria • Archaeabacteria • Animalia • Plantae • Fungi • Protista Bacteria Archaea Eukarya

37. Protists • Multicellularity evolved multiple times independently

38. Animalia • Blastula • Multicellular heterotrophs • Tripoblasty • Ectoderm • Endoterm • Mesoderm • Movement • Tube-within-tube • Complex nervous systems

39. Plantae • Photosynthesis • Cell wall • Sessile • 350,000 species • Land plants

40. Land Plants Vascular Gymnosperms Nonvascular Angiosperms

41. Fungi • Heterotrophs • Absorb their food • Cell walls • Spores • Decomposition

42. Evolution of Kingdoms