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COMPTETENCIESCOMPTETENCIESStudents, after mastering the materials of Students, after mastering the materials of Plant Physiology course, should be able to:Plant Physiology course, should be able to:1.1. To explain the assimilation of COTo explain the assimilation of CO22 to be carbohydrate to be carbohydrate

(sugars) in C(sugars) in C4 4 and CAM plantsand CAM plants2.2. To explain the diffusion of COTo explain the diffusion of CO22 from the atmosphere from the atmosphere

into the site of assimilation in the chloroplasts of Cinto the site of assimilation in the chloroplasts of C4 4 and and CAM plantsCAM plants

3.3. To explain reactions, enzymes and products involved in To explain reactions, enzymes and products involved in the reduction of COthe reduction of CO22 to be carbohydrate in Cto be carbohydrate in C4 4 and and CAM plantsCAM plants

2299//1010//20122012

C3 Plants: Avena Sativa (380x)

C4 Plants: (a). Zea maize (350x)(c). Gomphrena

(740x)

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COCO22 Fixation Fixation in Cin C33 vs. vs. CC44 PlantsPlants

Basic Reaction of CO2reduction in C4 plants

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1. NADP-malic enzyme type 2. NAD-malic enzyme type

3. Phosphoenolpyruvate carboxykinase type

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COCO22 Fixation in Fixation in a CAM a CAM PlantPlant COCO22 Reduction in CAM (Reduction in CAM (CrassulaceanCrassulaceanAcid Metabolism) PlantsAcid Metabolism) Plants

Diurnal regulation of CAM phosphoenolpyruvate (PEP) carboxylase which is achieved by phosphorylation of a serine residue. Ser = Serine

Physiological and Physiological and Ecological Aspects ofEcological Aspects of

PHOTOSYNTHESISPHOTOSYNTHESIS

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COCO22 compensation point compensation point for Cfor C4 4 plants plants -- COCO22 comp point is comp point is 00--5 5 PPM PPM for C for C 3 3 plants plants -- COCO22 comp point is comp point is 3030--70 70

PPM PPM C C 4 4 plants have developed mechanisms plants have developed mechanisms

for surviving and thriving in hotter, drier for surviving and thriving in hotter, drier climates. climates.

C C 3 3 plants survive and thrive in more plants survive and thrive in more moderate climates.moderate climates.

LIGHT = PAR = PPFD LIGHT = PAR = PPFD (Photosynthetic photon flux density)(Photosynthetic photon flux density)

Sifat optis dari daun kacang panjang

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Keadaan terbuka Keadaan ternaungi

Distribusi khloroplast dalamselAtas : penampang

membujurBawah :

Penampangmelintang

dark

maxEmax P/PPFDQEXP1PP

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Muhlenbergia montana plants grown at 26/16 °C day/night temperature. Arrows indicate the estimated light saturation points used in subsequent temperature response measurements.

TEMPERATURE & LIGHTTEMPERATURE & LIGHT

from M. montana grown at 26/16 °C or 26/4 °C day/night temperatures. Rubisco activity was determined on leaves of plants grown at 26/16 °C (mean±SE, N=4–6)

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CO2

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FFmm maximum fluorescence level after a maximum fluorescence level after a saturating light pulse on a darksaturating light pulse on a dark--adapted leaf adapted leaf

F′F′mm maximum fluorescence after a saturating maximum fluorescence after a saturating light pulse from a leaf during steadylight pulse from a leaf during steady--state state photosynthesisphotosynthesisFFoobasalbasal fluorescence level on fluorescence level on a darka dark--adapted leafadapted leaf

FF′′oo minimum fluorescence from a leaf following minimum fluorescence from a leaf following steadysteady--state illumination and quickly dark state illumination and quickly dark adapted under a pulse of faradapted under a pulse of far--red light to fully red light to fully oxidize PSIoxidize PSI

FFss steadysteady--state fluorescence on an illuminated state fluorescence on an illuminated leafleaf

in A. edulis wild-type plants

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