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Chloroplast movement in Alocasia macrorrhiza
The light requirements for chloroplast movements in a rainforest understory plant Alocasia macrorrhiza are characterized and the resulting changes in light penetration to different cell layers within the leaf and through the entire thickness of the leaf are characterized. Expand
Ultraviolet Radiation and the Snow Alga Chlamydomonas nivalis (Bauer) Wille ¶
Cells are protected against potentially high levels of UV radiation by the snow itself when they live several centimeters beneath the surface, and they rely on cellular screening compounds, chiefly astaxanthin, when located near the surface where UV fluxes are high. Expand
Photoacoustic Analysis Indicates That Chloroplast Movement Does Not Alter Liquid-Phase CO2 Diffusion in Leaves of Alocasia brisbanensis12
Resistance for CO2 estimated from oxygen permeability was in good agreement with published values, validating photoacoustics as another way of assessing internal resistances to CO2 diffusion to reduce CO2 limitation of photosynthesis. Expand
Measurement of the Optical Properties of Leaves Under Diffuse Light
Measuring leaf light absorptance is central to many areas of plant biology including photosynthesis and energy balance. Absorptance is calculated from measured values of transmittance andExpand
Circadian Stomatal Rhythms in Epidermal Peels from Vicia faba.
This work investigates circadian rhythms in apertures that persist in functionally isolated guard cells in epidermal peels of Vicia faba, and compares these rhythms with rhythms in stomatal conductance in attached leaves. Expand
A new paradigm in leaf-level photosynthesis: direct and diffuse lights are not equal.
It is shown that leaf-level photosynthesis in sun leaves of both C(3) and C(4) plants can be 10-15% higher under direct light compared to equivalent absorbed irradiances of diffuse light, and previously observed increases in canopy-level photoynthesis occur even though leaf- level photosynthesis decreases under diffuse light. Expand
Chloroplast movements in the field
A field-portable instrument was constructed, based on a pulsed measuring beam and lock-in detection that measures chloroplast movements in attached leaves by sensing the resultant changes in leaf transmittance, and found chloroplasts were in motion most of the time, rarely achieving the extreme anticlinal or periclinal positions. Expand
Surface gas-exchange processes of snow algae
Investigating surface gas-exchange characteristics of snow colonized by this red-colored chlorophyte found CO2 uptake up to 0.3 μmol m−2⋅s−1 in dense algal blooms indicates that summer snowfields can be surprisingly productive. Expand
The Light Environment and Cellular Optics of the Snow Alga Chlamydomonas nivalis (Bauer) Wille † ¶
The alga Chlamydomonas nivalis lives in a high‐light, cold environment: persistent alpine snowfields, and an integrating sphere to measure the spectral characteristics of a monolayer of cells and microscopic techniques to examine the spectral characteristic of individual cells were used. Expand