2.  SWBAT: Explain how timing and coordination of physiological and behavioral events are regulated by multiple mechanisms and involve interactions between environmental stimuli and internal molecular signals.

3.  How do each of these events or processes help the organism to maintain homeostasis?  What is the stimulus, receptor, response?  How do homeostasis, and these coordinated events in particular, relate to natural selection?

4.  We are talking about innate physiological responses and behaviors, NOT learned ones.

5.  Plants must respond to things such as Available light Passage of time (day/night, seasons)  Their response cannot be movement, so instead, they often respond with changes in their growth and development

6.  Plants responses include Phototropism Photoperiodism

7.  = growth toward (positive phototropism) or away from (negative phototropism) light  Controlled by auxins plant hormones that cause cells to lengthen by “loosening” the cell wall

8.  Auxin, produced in the apical meristem, always moves away from light so the cells farthest from the light source lengthen

10.  The elongation of the cells is made possible by the activation of proton pumps  Acidifies and thereby “loosens” the cell wall allow more water to enter  The cell wall is “stretched” in this way

12.  The response of an organism to the length of exposure to light throughout the day; length of day vs. night.

13.  Phytochrome – a protein in plants that changes shape when it absorbs light.  P R  P FR (named for the absorption spectrum)  The amount of P R vs. P FR, relates to the amount of light a plant has been exposed to over the day.

14.  This in turn, tells the plant what season it is and whether it is time to bloom (reproduce)  Poinsettia- long night, short day (winter)  Lettuce- long day, short night (summer)  SURVIVAL!

16.  Gibberellins = Work with auxins to elongate. Signal seeds to germinate  Abscisic acid = Slows growth Promotes dormancy Conserves water by closing stomata  Ethylene = Apoptosis –leaf shedding Fruit ripening

17.  Animals, especially humans, also respond to light and the amount of light stimulates in us a 24 hour “clock”.  Light  eyes  pineal gland  releases melatonin (mostly in the dark)

20.  Plants- phototropism and photoperiodism  Animals- circadian rhythms  Bacteria- quorum sensing

21.  A way that bacteria can communicate with others in their species or even other species  Autoinducers= proteins given off by bacteria that simply say “I’m here”  More bacteria = more autoinducers

22.  Behaviors related to density of population (and therefore autoinducers) Symbiosis Increased virulence Motility Biofilms

23.  Physiological events  Behavioral events

24.  Remember... These are innate behaviors NOT learned behaviors.  SURVIVAL!

25.  Hibernation= A physiological state in which metabolism decreases, the heart and respiratory system slow down, and body temperature is maintained at a lower level than normal. Cold  Estivation= hot dry

26.  Migration= a regular long-distance change in location  Courtship routines

27.  Resource partitioning = The differentiation of niches that enables similar species to coexist in a community  Mutualistic relationships Lichens- a symbiotic association of a fungus and photosynthetic microorganism Bacteria in the digestive tract Pollination

28.  All timed coordinated events Require communication within cells, between cells, or even between organisms. They are innate, NOT learned They help to maintain homeostasis They increase survival

29.  SWBAT: Explain how timing and coordination of physiological and behavioral events are regulated by multiple mechanisms and involve interactions between environmental stimuli and internal molecular signals.