Potentiometric titrations of Bacillus subtilis cells to low pH and a
... ⬃2 to 10. Bacterial cell walls lose their structural integrity and release significant quantities of cytoplasmic organic molecules at pH values above 10, so titrations can not examine protonation behavior in that pH range. Some structural damage occurs to the cell walls below pH 4 (Borrok et al., 20 ...
... ⬃2 to 10. Bacterial cell walls lose their structural integrity and release significant quantities of cytoplasmic organic molecules at pH values above 10, so titrations can not examine protonation behavior in that pH range. Some structural damage occurs to the cell walls below pH 4 (Borrok et al., 20 ...
Characterization of a cytokinesis defective (cyd1
... described where defects are known to occur in both mature vegetative and reproductive organs. Thus, the CYD1 gene product appears to be necessary for the execution of cytokinesis throughout the shoot. The examination of stomata by microscopy may be a useful screen for the directed isolation of addit ...
... described where defects are known to occur in both mature vegetative and reproductive organs. Thus, the CYD1 gene product appears to be necessary for the execution of cytokinesis throughout the shoot. The examination of stomata by microscopy may be a useful screen for the directed isolation of addit ...
Protists
... back to about 1.2 billion years ago compared to bacteria which appear about 3.5 billion years ago. We do not know how the various groups of protists are related to one another. We assume they arose from certain groups of bacteria, but when and how they came into being, scientists are still invest ...
... back to about 1.2 billion years ago compared to bacteria which appear about 3.5 billion years ago. We do not know how the various groups of protists are related to one another. We assume they arose from certain groups of bacteria, but when and how they came into being, scientists are still invest ...
Plant microtubule organization
... meeting at the midplane. They direct the transport of Golgiderived vesicles towards the centrifugally expanding cell plate, which matures to become the cross-wall separating daughter cells (Otegui and Staehelin, 2000a). Phragmoplast microtubules originate as a compact cylindrical bundle between the ...
... meeting at the midplane. They direct the transport of Golgiderived vesicles towards the centrifugally expanding cell plate, which matures to become the cross-wall separating daughter cells (Otegui and Staehelin, 2000a). Phragmoplast microtubules originate as a compact cylindrical bundle between the ...
green water: myths, facts, theories ii
... for a relationship between algae blooms and nutrient levels within the open areas of large bodies of water. Lakes and oceans become stratified with various areas having different nutrient, oxygen, and temperature levels, hence varying population conditions. Most of these scientific findings just si ...
... for a relationship between algae blooms and nutrient levels within the open areas of large bodies of water. Lakes and oceans become stratified with various areas having different nutrient, oxygen, and temperature levels, hence varying population conditions. Most of these scientific findings just si ...
Functional Utrastructure of Genlisea (Lentibulariaceae) Digestive
... material – cutin (Casparian strip). This wall is thickened especially at the base of the cell, where the middle cell is linked with the basal cell. The lateral wall apparently is brittle, because it fractures easily during material processing. The cell is strongly polarized. The vacuole occupies the ...
... material – cutin (Casparian strip). This wall is thickened especially at the base of the cell, where the middle cell is linked with the basal cell. The lateral wall apparently is brittle, because it fractures easily during material processing. The cell is strongly polarized. The vacuole occupies the ...
Arabidopsis – a powerful model system for plant cell wall research
... walls strengthen plant cells. Most cells use this strength to resist positive pressure generated within the cell; by harnessing this turgor pressure, plants are able to stand upright. In contrast, thick cell walls of water conducting vessels and tracheids enable these cells to resist substantial neg ...
... walls strengthen plant cells. Most cells use this strength to resist positive pressure generated within the cell; by harnessing this turgor pressure, plants are able to stand upright. In contrast, thick cell walls of water conducting vessels and tracheids enable these cells to resist substantial neg ...
Silicification in the Microalgae
... reproduction. Maximum size is restored after sexual reproduction (Round et al. 1990). Valve shape, patterns of pores on the valve face, and structural features on the valves are used as taxonomic characters. At present the diatoms are the only known group with species with an absolute requirement fo ...
... reproduction. Maximum size is restored after sexual reproduction (Round et al. 1990). Valve shape, patterns of pores on the valve face, and structural features on the valves are used as taxonomic characters. At present the diatoms are the only known group with species with an absolute requirement fo ...
Reconciling an archaeal origin of eukaryotes with engulfment: a
... framework eliminates such incompatibilities, and that an archaeal origin for eukaryotes (as suggested from recent phylogenies) can be uncontroversially reconciled with phagocytosis as the mechanism for engulfment of the mitochondrial ancestor. This is significant because it eliminates a perceived pr ...
... framework eliminates such incompatibilities, and that an archaeal origin for eukaryotes (as suggested from recent phylogenies) can be uncontroversially reconciled with phagocytosis as the mechanism for engulfment of the mitochondrial ancestor. This is significant because it eliminates a perceived pr ...
PDF
... are easily identified by their cell bodies in the ganglion cell layer (GCL), their processes in the IPL and their single axons extending into the nerve fiber layer. The one distinction that could not be based on morphology is between RPr and CPr (Fig. 1F,G). For this, we used an antibody, 4D2 (kindl ...
... are easily identified by their cell bodies in the ganglion cell layer (GCL), their processes in the IPL and their single axons extending into the nerve fiber layer. The one distinction that could not be based on morphology is between RPr and CPr (Fig. 1F,G). For this, we used an antibody, 4D2 (kindl ...
Defining retinal progenitor cell competence in
... are easily identified by their cell bodies in the ganglion cell layer (GCL), their processes in the IPL and their single axons extending into the nerve fiber layer. The one distinction that could not be based on morphology is between RPr and CPr (Fig. 1F,G). For this, we used an antibody, 4D2 (kindl ...
... are easily identified by their cell bodies in the ganglion cell layer (GCL), their processes in the IPL and their single axons extending into the nerve fiber layer. The one distinction that could not be based on morphology is between RPr and CPr (Fig. 1F,G). For this, we used an antibody, 4D2 (kindl ...
PDF
... Developmental models distill essential problems faced by cells, tissues and organisms into simplified and experimentally accessible systems. Stomata (the epidermal valves that mediate gas exchange between plants and the atmosphere) and the lineage from which they are derived have emerged as a pre-em ...
... Developmental models distill essential problems faced by cells, tissues and organisms into simplified and experimentally accessible systems. Stomata (the epidermal valves that mediate gas exchange between plants and the atmosphere) and the lineage from which they are derived have emerged as a pre-em ...
Stomatal development - The Company of Biologists
... Developmental models distill essential problems faced by cells, tissues and organisms into simplified and experimentally accessible systems. Stomata (the epidermal valves that mediate gas exchange between plants and the atmosphere) and the lineage from which they are derived have emerged as a pre-em ...
... Developmental models distill essential problems faced by cells, tissues and organisms into simplified and experimentally accessible systems. Stomata (the epidermal valves that mediate gas exchange between plants and the atmosphere) and the lineage from which they are derived have emerged as a pre-em ...
Form 3 (Track 2)
... the seeds should be planted during the month of November, with a distance of not less than 8cm apart from each other. Explain why plants will not germinate successfully if: (i) the student sows the seeds only 4cm apart (ii) the soil is waterlogged (iii) no water is added to the soil (iv) seeds are p ...
... the seeds should be planted during the month of November, with a distance of not less than 8cm apart from each other. Explain why plants will not germinate successfully if: (i) the student sows the seeds only 4cm apart (ii) the soil is waterlogged (iii) no water is added to the soil (iv) seeds are p ...
Determination of Symmetric and Asymmetric Division Planes in
... sizes, shapes, and/or developmental fates. For example, asymmetric cell divisions in root meristems follow a stereotyped pattern that establishes distinct cell layers with different identities and functions (1). Thus, understanding mechanisms governing the orientation of both symmetric and asymmetri ...
... sizes, shapes, and/or developmental fates. For example, asymmetric cell divisions in root meristems follow a stereotyped pattern that establishes distinct cell layers with different identities and functions (1). Thus, understanding mechanisms governing the orientation of both symmetric and asymmetri ...
Progress in understanding the role of microtubules in plant cells
... function in plant cells. Since their first clear description in 1963 in a publication by Ledbetter and Porter [1], in which the term ‘microtubule’ was first coined, the question of how and not whether microtubules control the orientation of cellulose microfibrils has been the central focus of most s ...
... function in plant cells. Since their first clear description in 1963 in a publication by Ledbetter and Porter [1], in which the term ‘microtubule’ was first coined, the question of how and not whether microtubules control the orientation of cellulose microfibrils has been the central focus of most s ...
Gram`s staining - Micro-Rao
... and Propionibacterium have cell walls particularly sensitive to breakage during cell division, resulting in Gram-negative staining of these cells. In cultures of Bacillus, and Clostridium a decrease in peptidoglycan thickness during cell growth may cause some of them to appear Gram negative. Certain ...
... and Propionibacterium have cell walls particularly sensitive to breakage during cell division, resulting in Gram-negative staining of these cells. In cultures of Bacillus, and Clostridium a decrease in peptidoglycan thickness during cell growth may cause some of them to appear Gram negative. Certain ...
Cell Wall Polysaccharides are Mislocalized to the Vacuole in
... protein (secGFP), which does not significantly fluoresce in the apoplast but accumulates in the endomembrane system of secretion mutants, has revealed several Arabidopsis genes required for protein secretion and cell wall synthesis (Zheng et al. 2004). ECHIDNA (ECH) is a protein of unknown function ...
... protein (secGFP), which does not significantly fluoresce in the apoplast but accumulates in the endomembrane system of secretion mutants, has revealed several Arabidopsis genes required for protein secretion and cell wall synthesis (Zheng et al. 2004). ECHIDNA (ECH) is a protein of unknown function ...
F-Box Protein FBX92 Affects Leaf Size in
... (Supplementary Fig. S1B). Because the phenotypes of the lines with the weakest overexpression were similar, we present here only the analysis of AtFBX92OE7 together with that of AtFBX92OE2 showing a stronger increase in expression level. In contrast to what was observed for plants that ectopically e ...
... (Supplementary Fig. S1B). Because the phenotypes of the lines with the weakest overexpression were similar, we present here only the analysis of AtFBX92OE7 together with that of AtFBX92OE2 showing a stronger increase in expression level. In contrast to what was observed for plants that ectopically e ...
DRP1 family in cytokinesis and cell expansion
... Although sucrose-rescued adl1A mutants display normal vegetative growth, they are highly infertile as a result of a maternal sporophytic defect in the mutant flowers that severely inhibits fertilization (Kang et al., 2001). We reasoned that the maternal defect could result from problems in the mutan ...
... Although sucrose-rescued adl1A mutants display normal vegetative growth, they are highly infertile as a result of a maternal sporophytic defect in the mutant flowers that severely inhibits fertilization (Kang et al., 2001). We reasoned that the maternal defect could result from problems in the mutan ...
the cell cycle in action - Oxford Academic
... balance in this ‘cycling’ process of NEDD8/RUB1 conjugation/deconjugation is absolutely required for the proper activity of the SCF complexes. Mutations that affect CSN activity lead to growth arrest and constitutive photomorphogenesis development. Recently, an interesting study revealed that CSN ac ...
... balance in this ‘cycling’ process of NEDD8/RUB1 conjugation/deconjugation is absolutely required for the proper activity of the SCF complexes. Mutations that affect CSN activity lead to growth arrest and constitutive photomorphogenesis development. Recently, an interesting study revealed that CSN ac ...
Effect of n-butanol and cold pretreatment on the cytoskeleton and
... technique reduces the time needed for the development of new, improved varieties. Developing microspores of higher plants possess the ability to switch their default gametophytic developmental program to the sporophytic pathway under certain circumstances. This process, called androgenesis can be in ...
... technique reduces the time needed for the development of new, improved varieties. Developing microspores of higher plants possess the ability to switch their default gametophytic developmental program to the sporophytic pathway under certain circumstances. This process, called androgenesis can be in ...
Full-Text PDF
... The cell wall is made of cellulose microfibrils connected through hemicellulose and embedded in a pectin matrix composed of polysaccharides. The composition of this polysaccharide network changes along the root, with a decrease in pectin and an increase in the hemicellulose xylan, from the meristema ...
... The cell wall is made of cellulose microfibrils connected through hemicellulose and embedded in a pectin matrix composed of polysaccharides. The composition of this polysaccharide network changes along the root, with a decrease in pectin and an increase in the hemicellulose xylan, from the meristema ...
1 - Purdue Department of Biological Sciences
... expressed in xylem of leaf-trace bundles and in phloem of stem bundles, correlated with transport activity in transfer cells and in the companion cells of sieve elements (Dahiya et al. 2005). In this paper, we describe a second molecular marker that is expressed exclusively in xylem of stem bundles. ...
... expressed in xylem of leaf-trace bundles and in phloem of stem bundles, correlated with transport activity in transfer cells and in the companion cells of sieve elements (Dahiya et al. 2005). In this paper, we describe a second molecular marker that is expressed exclusively in xylem of stem bundles. ...
Cell wall
The cell wall is a tough, flexible and sometimes rigid layer that surrounds some types of cells. It surrounds the cell membrane and provides these cells with structural support and protection. In addition, the cell wall acts as a filtering mechanism. A major function of the cell wall is to act as a pressure vessel, preventing over-expansion when water enters the cell. Cell walls are found in plants, fungi and prokaryotic cells but not in mycoplasmas.The composition of the cell wall varies between species and may depend on cell type and developmental stage. The primary cell wall of land plants is composed of the polysaccharides cellulose, hemicellulose and pectin. In bacteria, peptidoglycan forms the cell wall. Archaean cell walls have various compositions, and may be formed of glycoprotein S-layers, pseudopeptidoglycan, or polysaccharides. Fungi possess cell walls made of the glucosamine polymer chitin, and algae typically possess walls made of glycoproteins and polysaccharides. Unusually, diatoms have a cell wall composed of biogenic silica. Often, other accessory molecules are found anchored to the cell wall.