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More available water allows plants to keep stomata open and take up more CO2
More available water allows plants to keep stomata open and take up more CO2
Forums The Undercurrent it's literally just biology
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Some desert plants complete their life cycle (seed germinates → bloom) entirely in one rainy season
Some desert plants complete their life cycle (seed germinates → bloom) entirely in one rainy season
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Physiological or morphological adaptations: fleshy stems (store water for later use), reduced leaves and photosynthetic stems (resist water loss), CAM photosynthesis (CO2 uptake at night, stomata closed in daytime)
Physiological or morphological adaptations: fleshy stems (store water for later use), reduced leaves and photosynthetic stems (resist water loss), CAM photosynthesis (CO2 uptake at night, stomata closed in daytime)
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Translocation - transport of products of photosynthesis, carried out by phloem
Translocation - transport of products of photosynthesis, carried out by phloem
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Phloem sap - mostly sugar (sucrose) and some amino acids, hormones, minerals
Phloem sap - mostly sugar (sucrose) and some amino acids, hormones, minerals
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From sugar source (producer of sugar by photosynthesis or starch breakdown) to sugar sink (consumer or depository of sugar)
From sugar source (producer of sugar by photosynthesis or starch breakdown) to sugar sink (consumer or depository of sugar)
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Sinks receive sugar from nearby sources. Direction of transport in a sieve tube depends on location of source and sink connected by that tube
Sinks receive sugar from nearby sources. Direction of transport in a sieve tube depends on location of source and sink connected by that tube
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Sugar is loaded from mesophyll cells into sieve-tube elements, then exported to sinks
Sugar is loaded from mesophyll cells into sieve-tube elements, then exported to sinks
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Walls of companion cells have ingrowths to enhance transfer between apoplast and symplast
Walls of companion cells have ingrowths to enhance transfer between apoplast and symplast
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Sugar movement into phloem requires active transport (H+/sucrose cotransporter) b/c sucrose is more concentrated in sieve-tube elements and companion cells than in mesophyll
Sugar movement into phloem requires active transport (H+/sucrose cotransporter) b/c sucrose is more concentrated in sieve-tube elements and companion cells than in mesophyll
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Concentration of free sugar is always lower in sink than in sieve tube → unloads by diffusion, water follows by osmosis
Concentration of free sugar is always lower in sink than in sieve tube → unloads by diffusion, water follows by osmosis
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In angiosperms, translocation is driven by positive pressure (pressure flow)
In angiosperms, translocation is driven by positive pressure (pressure flow)
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Sugar concentration is higher at source than at sink, water moves in by osmosis and builds positive pressure at source
Sugar concentration is higher at source than at sink, water moves in by osmosis and builds positive pressure at source
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Self-thinning - when sinks > sources, plant aborts some flowers, seeds, or fruits
Self-thinning - when sinks > sources, plant aborts some flowers, seeds, or fruits
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Plasmodesmata are dynamic - open/close in response to turgor pressure, cytosolic Ca2+ levels, or cytosolic pH
Plasmodesmata are dynamic - open/close in response to turgor pressure, cytosolic Ca2+ levels, or cytosolic pH
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Close or are eliminated during differentiation (eg. when leaf matures from sink to source)
Close or are eliminated during differentiation (eg. when leaf matures from sink to source)
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Having you as a Voltie would be awesome.