-Read pg. What is your circadian rhythm?

1. -Read pg. What is your circadian rhythm? Fill out circadian rhythm sheet

2. Biological Clocks/Circadian Rhythms • A physiological cycle with a frequency of about 24 hours is called a circadian rhythm • Even without external, environmental cues, circadian rhythms persist in humans and in all eukaryotes • Example: jet lag in humans

4. Photoperiodism • A physiological response to day length (differs in winter, summer, spring, and fall) is known as photoperiodism • Short-day plants • Require a shorter light period • Flower in later summer/fall/winter • Example: poinsettias • Long-day plants • Require a longer light period • Flower in late spring/early summer • Example: spinach • Day-neutral plants • Are unaffected by photoperiod • Example: tomatoes • But it’s actually the night that matters!!

6. Plant Responses to Internal & External Signals

7. Plant Hormones • Hormones are chemical signals that coordinate the various parts of an organism • A hormone is a compound produced in one part of the body which is then transported to other parts of the body, where it triggers responses in target cells and tissues • Examples of human hormones: • Adrenaline, testosterone, estrogen, epinephrine…

8. Plant Hormones • There are 5 major classes of plant hormones, each with specific functions: • Auxin • Cytokinins • Gibberellins • Abscisic acid • Ethylene

9. Auxin • Stimulates stem elongation • Stimulates development of fruit • Involved in phototropism and gravitropism

10. Cytokinins • Stimulate cell division and growth • Stimulate cytokinesis • Stimulate germination and flowering

11. Gibberelins • Trigger seed and bud germination • Promote stem elongation and leaf growth • Important in the growth of fruit

12. Ethylene • Promotes fruit ripening • Senescence (aging) is a progression of irreversible change that eventually leads to death • Caused, at least in part, by ethylene • “One bad apple spoils the whole bunch”

13. Abscisic Acid • Induces seed dormancy • Anti-gibberellin • Inhibits cell growth • Anti-cytokinin • Inhibits fruit ripening • Anti-ethylene • Closes stomata during water stress, allowing many plants to survive droughts

14. Tropisms • Tropisms are growth responses that result in curvatures of whole plant organs toward or away from a stimuli • There are three major stimuli that induce tropisms • Light (Phototropism) • Gravity (Gravitropism) • Touch (Thigmotropism)

15. Phototropism • Phototropism is the growth of a shoot towards light • This is primarily due to the action of auxin • Auxin elongates the cells on the non-light side

16. Plant Defenses • Plants defend themselves against herbivores in several ways • Physical defenses, such as thorns • Chemical defenses, such as producing distasteful/toxic compounds

17. interactions between root, stem, leaf, • flower color based on pH

18. To do #1 -Make a list of plant hormones and their functions -Compare circadian rythm, phototropism, and photperiodism

19. Fungi and Plants http://www.wisc-online.com/objects/ViewObject.aspx?ID=BIO304

20. Fungi

21. Fungi--Nutrition and Habitat - Decomposers/Absorptive heterotrophs - saprobic, parasitic, mutualistic

22. Classification of Fungi Chytridiomycota - uniflagellated spores - link to protists? Zygomycota - zygosporangia - black bread mold (Rhizopus stolonifer) Asomycota - spores produced in asci (sac-like structure) - truffles (Tuber melanosporum) Basidiomycota - spores formed in basidiocarps - mushrooms

23. Structure - hyphae form mycellium

24. Growth and Reproduction

25. Only fungi form fruiting bodies and spores

26. Above: The common mold Rhizopus decomposing strawberries Right: Pilobolus aiming its sporangia. Pilobolus, the hat thrower. Pilobolus is a dung-loving (coprophilous) fungus. Spores are dispersed up to 2 m away and stick to grass blades in the vicinity. The grass and caps are eventually eaten by herbivores.

27. Zygomycota

28. Coenocytic and septate hyphae

29. Life cycle of bread mold WATCH--http://bcs.whfreeman.com/thelifewire/content/chp31/31020.html Use these 10 terms to explain the life cycle of a bread mold • Hyphae • Sporangia • Spore • Asexual • Sexual • Pheromones • Zygosporangium • Nuclei • Haploid • Diploid

30. Asomycota

31. Clockwise: Scarlet cup; the Yellow morel; truffels

32. Fungal gills, Hypholoma fasciculare (Basidiomycota). The gills hang down from the cap in a tightly packed array. By producing gills in this way the mushroom can increase the surface area of the fertile layer (hymenium) by a factor of 20 or more.

34. Molds, Yeasts, Lichens and Mycorrhizae - represent unique lifestyles that evolved independently Molds Penicillium on an orange, soft rot of citrus. The name Penicillium comes from penicillus = brush, and this is based on the brush-like appearance of the fruiting structure under the microscope.

35. Yeasts - unicellular fungi that inhabit moist habitats - Saccharomyces cerevisiae - baker/brewer yeast - Candida - inhabit human epithelial tissue - AIDS patients

36. Lichens - symbiotic association b/n fungi and algae - mutual exploitation - tough, resistant; but sensitive to air pollution

37. Mycorrhizae - mutualistic associations with plant roots - increases the absorptive surface area of plant roots - exchange of minerals between plant and fungus

38. To do #2 -Watch life cycle of a bread mold -Write a summary of the life cycle of bread mold