Plant physiology - Chapter 12 Assimilation of Mineral Nutrients potx

... deter-mined by plant tissue analysis.Proper use of plant tissue analysis requires an under-standing of the relationship between plant growth (oryield) and the mineral concentration of plant ... soil, plants encounter salt stress. Whereasmany plants are affected adversely by the presence of rel-atively low levels of salt, other plants can survive high lev-els (salt-tolerant plants) ... nitrogen-fix-ing bacteria, often participate with roots in the acquisition of nutrients. The study of how plants obtain and use mineral nutrients is called mineral nutrition. This area of research is central...

... In addition, these plants do notextend their hypocotyls in response to far-red light givenat the end of each photoperiod (called the end -of- day far-redresponse). Both of these responses ... chloroplast pro-teins: the small subunit of ribulose-1,6-bisphosphate car-boxylase/oxygenase (rubisco) and the major light-harvest-ing chlorophyll a/b–binding proteins associated with thelight-harvesting ... presentat low levels in light-grown plants because of its instabilityin the Pfr form, the phyA-mediated suppression of tran-scription of its own gene, and the instability of its mRNA.Type II phytochrome...

... AMO-1618ControlAMO-1618AMO-1618 + GA20AMO-1618 + GA13010200 12 Stem length (cm)4014 16 18 20 22 24(B) BX- 112 Number of long daysControlBX- 112 BX- 112 + GA20BX- 112 + GA1AMO-1618, which ... light-grown plantswould contain less GA1than dark-grown plants. However,light-grown plants turned out to contain more GA1thandark-grown plants—indicating that de-etiolation is a com-plex ... and transla-tion.2. Heavy-isotope- and radioactive-isotope-labelingstudies demonstrated that the stimulation of α-amy-lase activity by gibberellin involved de novo synthe-sis of the enzyme...

... phosphoryla-tion and activation of a subset of the type-B ARR proteins.Activation of the type-B proteins (transcription factors)leads to the transcriptional activation of the type-A genes.The type-AARR ... auxin. The principal cytokinin of higherplants—zeatin, or trans- 6-( 4-hydroxy-3-methylbut-2-eny-lamino)purine—is also present in plants as a riboside orribotide and as glycosides. These forms ... activity and identified it as trans- 6-( 4-hydroxy- 3- methylbut-2-enylamino)purine, which he called zeatin:The molecular structure of zeatin is similar to that of kinetin. Both molecules are adenine...

... changed.(A)(B)(D)(C)Amplitude Period12D 12L26 h24 h12D 12L 12D 12L (h)(h)12D 12L 12D 12L 12D 12L (h)LightpulseRephasedrhythmLightFIGURE 24.15 Some characteristics of circadian rhythms.amplitude ... lengthRRFRFRRRRFRFRRLong-day (short-night) plant Short-day (long-night) plant FIGURE 24.22 Phytochrome control of flowering by red (R) and far-red(FR) light. A flash of red light dur-ing the dark period ... greenhouse. (University of Wisconsin graduate students used for scale.) (Photocourtesy of R. Amasino.)618Long-day plants(LDPs)Short-day plants(SDPs)8161014 12 12141016818620422224...

... frames of reference of a biological unity.This chapter provides an overview of the basic anatomy of plants,from the organ level down to the ultrastructure of cellular organelles. Insubsequent chapters ... outer diameter of 25 nm; they are com-posed of polymers of the protein tubulin. The tubulinmonomer of microtubules is a heterodimer composed of two similar polypeptide chains ( - and β-tubulin), ... the polarity of the - and β-tubulin het-erodimer; in microfilaments, the polarity arises from thepolarity of the actin monomer itself. The opposite ends of microtubules and microfilaments are...

... [L](Leu)Isoleucine [I](Ile) - COO - COO - COO - COO - COO - COOCCH2C - COO - COO - COO - COO - COO - COO - COO - COO - COO - COO - COO - COO - COO - COO - COOH3N+H3N+H3N+++H3N+H3N+H3N+H3N+H3N+H3N+H3N+H3N+H3N+H3N+H3N+H3N+H3N+H3N+H3N+H3N+H2N+Figure ... configuration. Rubisco (D-ribulose-1,5-bisphos-phate carboxylase/oxygenase) catalyzes the addition of carbon dioxide to D-ribulose-1,5-bisphosphate to formtwo molecules of 3-phospho-D-glycerate, the ... ATP, Pi, fructose-6-phosphate, dihy-droxyacetone phosphate, and 3-phosphoglycerate. Therole of fructose-2,6-bisphosphate in plant metabolismwill be discussed further in Chapters 8 and 11.SummaryLiving...

... within the Plant Just as Ywvalues depend on the growing conditions andthe type of plant, so too, the values of Yscan vary consid-erably. Within cells of well-watered garden plants (exam-ples ... index of the water stress the plant is experiencing (see Chapter 25).Figure 3 .12 also shows representative values for Ywatvarious stages of water stress. In leaves of well-wateredplants, ... measure of the water status of a plant. Because of tran-spirational water loss to the atmosphere, plants are seldomfully hydrated. They suffer from water deficits that lead toinhibition of plant...