1 / 30

Tree of Life

Tree of Life. Figure 4.24. Fungi. Eukaryotic Mostly multicellular Some unicellular (molds, yeasts) Heterotrophs > 500 marine species Important decomposers Parasites (seagrasses, mollusc shells) Source of antibiotics (like the Penicillium fungi) (remember bioprospecting?)

maeve
Download Presentation

Tree of Life

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript


  1. Tree of Life Figure 4.24

  2. Fungi • Eukaryotic • Mostly multicellular • Some unicellular (molds, yeasts) • Heterotrophs • > 500 marine species • Important decomposers • Parasites (seagrasses, mollusc shells) • Source of antibiotics (like the Penicillium fungi) (remember bioprospecting?) • Symbionts – lichens, filament-like growths on algae provide structural support, while algae provides food

  3. Tree of Life -All have leaves, stems, roots, -Specialized tissues to transport water, nutrients, food from photosynthesis Figure 4.24

  4. Flowering Plants (Angiosperms)- produce fruit with seeds • Seagrasses (50 – 60 species) • Not true grasses (related to lilies) • Roots, stems and shoots grow from horizontal rhizome • Flowers typically small and inconspicuous Eelgrass (Zostera) – Temperate Atl, Pac; Tropical Pac Turtle grass (Thalassia) – Tropical Temperate Pac

  5. Flowering Plants (Angiosperms) – • Salt Marshes • Cord grass (Spartina) • Pickleweed (Salicornia) Spartina Salicornia

  6. Flowering Plants (Angiosperms) • Mangroves Avicennia: grey or black mangrove Variety of trees and shrubs Tropical/subtropical Salt tolerant-osmosis issue Thick leaves Viviparous-form propagules Rhizophora: red mangrove

  7. Flowering Plants (Angiosperms) • Mangroves vs Salt Marshes

  8. Invasive mangroves in San Diego’s Mission Bay

  9. Photosynthesis & Primary Production

  10. What is photosynthesis? What are autotrophs? Solar energy 6CO2 + 6H2O → C6H12O6 + 6O2 Fig. 4.5 Photosynthesis new organic compounds • Solar energy powers the reaction • Carbon dioxide and water used to make glucose • Oxygen gas is released as a by-product inorganic materials

  11. Photosynthesis Fig. 4.8b What absorbs light energy? - Chloroplast contains the photosynthetic pigment chlorophyll -Absorbs mainly red and violet- blue regions of visible light Chl a absorbance Fig. 4.6

  12. Fig. 4.5 Cellular Respiration 6CO2 + 6H2O ← C6H12O6 + 6O2 Chemical energy • opposite of photosynthesis • Releases energy in glucose, organisms store in ATP molecules until use • - Both autotrophs and heterotrophs respire

  13. Primary Production (P°) • What is primary production? • Net gain in organic matter that results when autotrophs photosynthesize more than they respire, i.e., P >>> R • ****Requires nutrients for organisms to grow, reproduce**** • This organic matter (new plant material) is available for heterotrophs

  14. Primary Production • ‘primary’ production because photosynthesis is the basis of most marine biomass production • Primary productivity is the rate of primary production, the rate at which plant material is produced

  15. Pmax photoinhibition Pn Photosynthesis (P) Pg + 0 - Compensation point respiration Ic Light intensity (I) Photosynthesis as a function of Light Intensity (P vs. I) Pg – Gross Primary Productivity Pn – Net Primary Productivity Pmax – maximal photosynthesis value Ic – compensation light intensity

  16. Pmax photoinhibition Pn Photosynthesis (P) Pg + 0 - Compensation point Respiration R Ic Light intensity (I) Gross photosynthesis: Total photosynthesis before subtracting respiration Net photosynthesis: Gross photosynthesis minus respiration, i.e. Pg – R Is available to support other trophic levels Compensation point: Light intensity when photosynthesis equals respiration, i.e. P = R Lower part of the photic zone

  17. Ecological Zonation of the Marine Environment Photic Zone Fig. 10.20

  18. Photic Zone • Part of the pelagic that light penetrates (0 to 100-200m) • Clarity of water: • Seasons • Location • Phytoplankton carry out photosynthesis • Primary Production (Pº) is at maximum • Responsible for up to 95% of all marine primary production • start of the marine food chain

  19. Marine Organisms Grouped by Lifestyle Fig. 10.19

  20. 2 easy ways to measure primary production • Either measure Oxygen (endpoint of the photosynthesis reaction) • Or measure Chlorophyll a (approximates phytoplankton biomass

  21. Today’s Lab:measuring photosynthesis = Pn = R = Pg Fig. 10.15

  22. Photosynthesis – Primary Production Experiment Purpose: To determine if more light produces more Net photosynthesis (Pn). Hypothesis: Net photosynthesis (Pn) in high light conditions will be greater than Net photosynthesis (Pn) in a low light environment.

  23. Methods • Six groups of 2 people (some groups will have 3) • Each group gets 2 BOD (Biological Oxygen Demand) bottles. 1 will be the LIGHT bottle and the other the DARK bottle. • Three groups will keep bottles under the high light and three will put bottles in low light. • Measure and record t=26 hrs oxygen concentration in mg/L. Do NOT remove foil until you take the measurement. Use the same DO meter. (t=0 was already done) • Each group measure light levels in two environments

  24. Results • Adjust initial and final oxygen concentrations • Light levels • Record light levels in high light and low light conditions for comparison • Errors? • Record any animals. • Record bubbles in light bottle.

  25. Results • Adjust initial and final oxygen concentrations • Light levels • Record light levels in high light and low light conditions for comparison • Errors? • Record any animals. • Record bubbles in light bottle.

  26. Results-photosynthesis experiment Calculations Gross photosynthesis Pg = (Final O2-Initial O2) in Light Bottle – (Final O2-Initial O2) in dark bottle Incubation period Incubation period Net photosynthesis Pn= (Final O2-Initial O2) in light bottle = Pg – R Incubation period Respiration R = (Initial O2-Final O2) in dark bottle Incubation period Units Oxygen concentration: mg L-1 Incubation time: hr Pg, Pn, R: mg oxygen L-1 hr-1

  27. Nutrient experiment • Purpose: To evaluate if nutrient (nitrate) concentration has an effect on phytoplankton • Hypothesis: Increased nitrogen concentration yields increased chlorophyll a production, and therefore, phytoplankton biomass • What was done ahead of time: • Dr. Gorga took a phytoplankton culture, controlled for light and nutrients, and added NO3 in 3 different concentrations (0, 200, and 450 mM ) • We will measure chlorophyll a (fluorescence as a proxy)

  28. Methods • Take bottle with phytoplankton, • Filter using vacuum-filtration apparatus • Place filter in tube, add methanol, agitate and crush filter with metal spatula • Put in freezer (-20oC) for 5 minutes • Centrifuge vial at top speed (5 minutes) • Transfer supernatant to cuvette (~ 2 ml) • Put cuvette in fluorometer, read fluorescence • Convert to chlorophyll a (fluorometer does this)

  29. Lab Report • Write up two experiments: • How light and nutrients affect phytoplankton production (of oxygen, of cells/biomass) • Bring two copies to class-due in class, October 9th, 10th • Part of grade will be review of colleague’s report (worth 5 points of 25 total report grade) • Reports: double spaced, 4-5 pages, include tables and figures as needed • Figures, plot light versus average Pn (remember legend), plot nutrient concentration versus chlorophyll a • Remember the big picture/broader impact for discussion/introduction: • how light and nutrients affect phytoplankton production in the ocean, • what about nutrient limitation, light limitation • changes in both over time, with nutrients in proximity to coastal zone (humans) • Cloudy versus sunny days

More Related