Multicellular Diversity

1. Multicellular Diversity Chapter 3 pp.88 - 151 SBI 3U1

2. Section 3.1 SBI 3U1 pp. 90 – 95 From Algae to Terrestrial Plants

3. Algae Where does this organism belong? Protists OR Plant Kingdom

4. Multicellular Algae Six Phlya of algae 3 phlya of single-celled, plant-like protists 3 phyla of seaweed (large, multicellular algae) based on colour

5. Brown Algae • Largest, most complex protists • Abundant, key components of marine and tidal environ. • Some grow 60 m in height, form underwater forests • Food and shelter for many species • Specialized tissues but NO true leaves or roots • The holdfast anchors the brown algae to a rock or hard structure while the blades take in light and carbon dioxide for photosynthesis

6. Red Algae • Can grow to 1m in length • Found in warm coastal tropical oceans • Contain green chlorophyll • Phycoerythrin pigment allows red algae to grow at ocean depths of 100 m or more and makes them appear red • Specialized tissues but NO true leaves or roots • Source of food Nori found in sushi, ice cream, & other food products

7. Green Algae • Most in freshwater, some in saltwater • Found in many ecosystems (surface of trees, sea ice, fur of sloths (mammals found in South Ameriaca Tropical Rain Forests) • Structurally diverse (unicellular, multicellular, flagella) • Same type of chlorophyll, colour as most land plants • Cell walls have cellulose & store food as starch

8. Benefits to Humans • Oxygen for humans • Vitamins • Fertilizers • Cosmetics • Paint • Petroleum (brown algae store food as oils)

9. The Shift to Land It is hypothesized that green algae are the closest evolutionary relatives of land plants based on several structures • Chlorophyll (same type as plants, chlorophyll a and b) • Cellulose cell walls • Store food energy as starch • DNA analysis show similarities

10. Adaptations to Life on Land 1) Plant Embryos 2) Vascular Tissues 1st land plants were small, simple, eventually developed tissues to transport materials over long distances Vascular Tissue contains: Xylem (carries minerals & H20 from roots to the rest of the plant) Phloem (transport sugars) • Plants reproduce using embryos • Embryos are small, simple, multicellular plants that are dependent on the parent plant for a time

11. Adaptations to Life on Land 3) Roots 4) Leaves Increased the surface area of the plant above ground Improving photosynthesis • Vascular Tissue allowed the evolution of roots • Strong anchoring ability to land • Cells specialized in absorbing and transporting water and nutrients

12. Evolution of land plants

13. To Do List • Learning Check, p. 93 # 1 – 6 • Review Questions, p. 95 # 1 – 5, 8 – 10

14. Section 3.2 SBI 3U1 pp. 96 – 104 The plant kingdom

15. Non-vascular plants:Bryophytes • Are considered to be the first type of land plant • 3 phyla: mosses, liverworts & hornworts • No vascular tissue, rely on diffusion & osmosis to move nutrients • Can hold large quantities of water • No roots, have small structures called rhizoids • In ecosystems, role to recycle nutrients • Potential sources of pharmaceuticals

16. Bryophyte Phyla

17. Seedless Vascular Plants • 4 phyla: whisk fern, club mosses, horsetails and ferns • Vascular tissue enabled plants to grow tall • Ferns are the most diverse • Ferns are found on the floors of temperate forests through Canada

18. Seedless Vascular Plants Phyla

19. Seed-producing Vascular Plants • Seeds allow plants to reproduce sexually without needing water and provides protection against harsh environment conditions • Two groups: • Gymnosperms • Angiosperms

20. Gymnosperm Diversity • Seeds are exposed on surface of cone scales • Gymnosperm means ‘naked seed’ • In cool boreal & alpine ecosystems of Canada • Most are evergreens  photosynthesis when conditions are suitable Examples: conifers such as pines, spruce, cedars

21. Angiosperm Diversity • Flowering plants • Seeds are contained in a fruit • Extensive diversity • Divided based on seed structure: 1) monocots(1 cotyledon), 2) dicots(2 cotyledons) • A cotyledon is a structure in the embryo that that helps to nourish the plant as it first starts to grow

22. To Do List • Learning Check, p. 97 # 7 – 9, 11, 12 • Learning Check, p. 101 #13, 15 • Review Questions, p. 104 # 1, 5 - 10

23. Section 3.3 SBI 3U1 pp. 105 – 110 The Fungus kingdom

24. Characteristics • 100,000 species of fungi (pl.), fungus (sg.) • Eukaryotes (including mushrooms, moulds, mildews & yeast) • Heterotrophs, stationary • Feed by releasing digestive enzymes into their surroundings, and then absorbing the digested nutrients into their cells

25. Structure of Fungi Basic structural units that make up the body of a multicellular fungus are called hyphae Hyphaeare denselypackedin a tight mass andare the basic structural unit of a fungus Fruiting body is the reproductive structure above ground, visible Mycelium is the branching network not visible, living in soil or other nutritious substances

26. Fungal Nutrition • Release enzymes that break down food externally • Then absorb nutrients from the food through cell membrane • Fungi can be classified into 4 groups based on how they obtain nutrients • Parasitic – live on or in a living organism e.g. Athlete foot • Predatory – trap & kill organisms e.g. Soil fungi ‘Arthrobotrys’ • Mutualistic – living in symbiotic relationship (both benefit) with other organism e.g. Lichens • Saprobial – living on dead organic matter e.g. Mushrooms, bread mould

27. Types of Fungal Nutrition

28. Fungal Reproduction • Both asexual and sexual methods of reproduction • Asexual methods: • Spore production- involves mitosis giving rise to reproductive cells called spores that develop into a new organism after dispersal. • Budding – Smaller cell develops while attached to parent & eventually pinchs off, becoming a new individual • Fragmentation – a piece of mycelium breaks and forms a new individual • Sexual methods: • Meiosis – 2 spores fuse, creating new organism

29. Fungal Classification Five Phyla Groups Classified on reproduction and structure

30. 1)Deuteromycota • Reproduce asexually • Diverse • Not closely related (left over fungi group) • Important for humans • Mould on fruit penicillium, same mould produces antibiotic penicillin • Cyclosporine (soil fungi) given to patients after transplant surgery to suppress immune system thus reducing the chances of the body rejecting the transplanted organ

31. 2) Chytridomycota • Mostly unicellular • Many aquatic, spores have flagella • Can be parasites or live on decaying plants or insects Impact on humans • Synchytriumendobioticum, infects potato plants and causes a disease called ‘potato wart’

32. 3) Zygomycota • Multicellular, mostly terrestrial • Asexual & sexual reproduction Zygospores  are diploid structures that develop after two haploid hyphae combine and fuse together  remain dormant until conditions are favourable to grow. Example • Rhizopus, bread mould

33. 4) Ascomycota • Largest group of fungi • Most reproduce sexually when 2 hyphal structure mate to form spore bearing asci • Most obtain nutrition by breaking down materials in wood and bone • Some are parasites of plants (e.g. chestnut blight, dutch elm disease) • Single-celled yeast part of this group, reproduce asexually by budding

34. 5) Basidiomycota • Mushrooms, some are edible • Some are parasites of plants • Basidium a club-shaped hypha that bear spores called basidiospores in this group • See ‘Life Cycle of a Mushroom’ p. 109, Fig. 3.21

35. Life Cycle of a Mushroom

36. Lichens • Are composite organisms that consist of a fungus and a photosynthetic organism that form a partnership that each partner depends on • Can live in extreme, harsh, nutrient poor environments • Important food source for many animals • Source of natural dye to colour wool & litmus paper

37. To Do List • Learning Check, p. 107 # 19 – 23 • Review Questions, p. 108 # 2, 4 – 7, 12, 14, 15

38. Section 3.4 SBI 3U1 pp. 111 – 124 The Animal kingdom

39. Animal Kingdom 35 phyla represents large diverse group of insects, sponges, worms, fish, birds, etc.

40. Characteristics to Classify Animals 1) Levels of organization 2) Number of body layers 3) Symmetry & body plans 4) Body cavity 5) Segmentation 6) Movement 7) Reproduction 8a) Invertebrates, 8b) Vertebrates

41. 1) Levels of Organization • All animals have cells which are organized into tissues, ONLY animal exception ‘sponges’ • A tissue is a group of similar cells that is specialized to perform specific tasks.(e.g. muscle tissue generates the force needed to move the body) RECALL: cells  tissues  organs  organ systems  organism

42. 2) Number of Body Layers • All animals EXCEPT ‘sponges, corals, hydras, jellyfish & sea anemones have 3 layers of cells LAYERS: • Ectoderm – outer layer produces the skin, nerve tissue and some sense organs • Mesoderm – middle layer produces muscles, blood, kidneys and reproductive organs • Endoderm – inner layer produces lungs, liver, pancreas, bladder and stomach lining

43. 3) Symmetry & Body Plans • Different arrangements of cells, tissues & organs leads to different body plans • ‘Sponges’ are animals with asymmetrical body plans, irregular body shape • Radial Symmetry • Bilateral Symmetry • Animals can be divided into • two mirror halves only along • one plane through the • central axis • Animals can be divided • along any plane parallel with • the body axis

44. 4) Body Cavities • Some animals have their digestive tract and other organs suspended in a fluid-filled body cavity called the coelom • Structure is solid, rigid but allows fluidity of organs • Acoelomate Body Plan • No coelom • Coelomate Body Plan • Has coelom

45. 5) Segmentation • Some animals (worms, scorpion) are segmented Segmentation  the division of the body into repetitive sections/segments Advantages: 1) effective mobility as segments move Independently 2) If a segment is damaged, other segments still function

46. 6) Movement • Nerve and muscle tissue allowed the development of complex and fast movement in most animals Sessile  fixed in one spot, unable to move independently Example  sponges move when young but as adults become stationary (sessile)

47. 7) Reproduction • Most animals reproduce sexually, some alternate between asexual & sexual • Haploid cells (cells containing unpaired chromosomes) (egg & sperm)  fertilization  zygote • Zygote develops into a diploid organism (organism with cells that have paired chromosomes) Internal Fertilization  egg and sperm combine INSIDE the female body e.g. humans External Fertilization  egg and sperm combine OUTSIDE the body e.g. Fish (usually aquatic environments)

48. 8a) Invertebrate Animals Animals WITHOUT backbones 95% of animals are invertebrates!

49. Sponges (Phylum Porifera) Sponges  asymmetrical body  no tissues, 2 layers of cells  adults are sessile (stationary) feed by trapping food particles in water as the water passes through the internal channels of their bodies

50. Cnidarians (Phylum Cnidaria) Cnidarians  hydras, jellyfish, sea anemones & corals  2 layers of cells  have tissues (muscle, simple nerve) swim and catch prey, digested in body cavity radial body symmetry two basic body forms