Chapter 7 Test A
... a. Eukaryotes were the first types of cells to exist. b. Chloroplasts arose when photosynthetic prokaryotes were engulfed by a larger cell but were not digested. c. Cells cannot exist without a nucleus to contain their DNA. d. All cells have a cell membrane, cytoplasm, ribosomes, and DNA. 15. Chloro ...
... a. Eukaryotes were the first types of cells to exist. b. Chloroplasts arose when photosynthetic prokaryotes were engulfed by a larger cell but were not digested. c. Cells cannot exist without a nucleus to contain their DNA. d. All cells have a cell membrane, cytoplasm, ribosomes, and DNA. 15. Chloro ...
Plant mitochondria move on F-actin, but their positioning in the
... disc-shaped and the strand-like structures. But it is again their positioning into clear parallel arrays, transverse or oblique to the cell axis which is the most striking feature (Fig. 3I). In cells treated with oryzalin, all transverse arrays of mitochondria are lost (Fig. 3E) and mitochondria are ...
... disc-shaped and the strand-like structures. But it is again their positioning into clear parallel arrays, transverse or oblique to the cell axis which is the most striking feature (Fig. 3I). In cells treated with oryzalin, all transverse arrays of mitochondria are lost (Fig. 3E) and mitochondria are ...
pdf: Rahman et al. 2007.
... expansion and division (Beemster and Baskin, 1998; Green, 1976). Furthermore, within an organ growth zone, division and expansion depend not only on the rate at which each process happens in each cell, but also on the numbers of cells dividing and elongating at any one moment. Although auxin has bee ...
... expansion and division (Beemster and Baskin, 1998; Green, 1976). Furthermore, within an organ growth zone, division and expansion depend not only on the rate at which each process happens in each cell, but also on the numbers of cells dividing and elongating at any one moment. Although auxin has bee ...
The role of the cytoskeleton in the polarized growth of
... involved in the incorporation of new membrane and cellwall material, can be observed by electron microscopy (Akashi etal., 1993; Grove, 1978). The similarity in terms of distribution between actin and wall vesicles suggests that the accumulation of F-actin is probably involved in the localization of ...
... involved in the incorporation of new membrane and cellwall material, can be observed by electron microscopy (Akashi etal., 1993; Grove, 1978). The similarity in terms of distribution between actin and wall vesicles suggests that the accumulation of F-actin is probably involved in the localization of ...
7-3 Cell Boundaries
... direction from which the materials would normally move—that is against a concentration difference. This process is known as active transport. Active transport requires energy. ...
... direction from which the materials would normally move—that is against a concentration difference. This process is known as active transport. Active transport requires energy. ...
C.Prinz, J.O. Tegenfeldt, R.H. Austin, E.C. Cox, J.C. Sturm, "Bacterial chromosome extraction and isolation," Lab Chip, 2, pp. 207-212 (2002).
... A mold for the mixer device was made at the center for Photonics and OptoElectronics Materials (POEM) in Princeton, NJ. The mold was fabricated on a silicon wafer using the epoxybased negative resist SU-8 (Microchem Corp, Newton, MA) according to standard protocol. The resist was spun on the wafer t ...
... A mold for the mixer device was made at the center for Photonics and OptoElectronics Materials (POEM) in Princeton, NJ. The mold was fabricated on a silicon wafer using the epoxybased negative resist SU-8 (Microchem Corp, Newton, MA) according to standard protocol. The resist was spun on the wafer t ...
Text for Slides on The Gravitational and Space Biology of Plants
... was removed from both of these roots before they were placed horizontally. The upper root was not treated further and failed to respond to gravity. On the lower root, a small amount of auxin was applied to its lower side by a small block of agar containing the hormone. This caused the root to bend d ...
... was removed from both of these roots before they were placed horizontally. The upper root was not treated further and failed to respond to gravity. On the lower root, a small amount of auxin was applied to its lower side by a small block of agar containing the hormone. This caused the root to bend d ...
Text for Slides on The Gravitational and Space Biology of Plants
... was removed from both of these roots before they were placed horizontally. The upper root was not treated further and failed to respond to gravity. On the lower root, a small amount of auxin was applied to its lower side by a small block of agar containing the hormone. This caused the root to bend d ...
... was removed from both of these roots before they were placed horizontally. The upper root was not treated further and failed to respond to gravity. On the lower root, a small amount of auxin was applied to its lower side by a small block of agar containing the hormone. This caused the root to bend d ...
Cell polarity - Philosophical Transactions of the Royal Society B
... different regions, apical and basal. Moreover, the plasma membranes are different and can transport molecules in different directions. While there is very good evidence for these differences, there is no evidence for polarity between the two regions in the form, for example, of a gradient or molecul ...
... different regions, apical and basal. Moreover, the plasma membranes are different and can transport molecules in different directions. While there is very good evidence for these differences, there is no evidence for polarity between the two regions in the form, for example, of a gradient or molecul ...
Cell Boundaries - kathrynbvirtualnotebook
... protection and support. In addition to lipids, most cell membranes contain protein molecules that are embedded in the lipid bilayer. Carbohydrate molecules are attached to many of these proteins. In fact, there are so many kinds of molecules in cell membranes that scientists describe their understan ...
... protection and support. In addition to lipids, most cell membranes contain protein molecules that are embedded in the lipid bilayer. Carbohydrate molecules are attached to many of these proteins. In fact, there are so many kinds of molecules in cell membranes that scientists describe their understan ...
Ultrastructure of the Infectious and Reproductive
... The most remarkable feature of the IF is its huge amount of periplasmic material. Although a number of proteins are located in the periplasm (Gortz et al., 1988; and unpublished), the nature and significance of the periplasmic material are largely unknown. During the infection process the IF always ...
... The most remarkable feature of the IF is its huge amount of periplasmic material. Although a number of proteins are located in the periplasm (Gortz et al., 1988; and unpublished), the nature and significance of the periplasmic material are largely unknown. During the infection process the IF always ...
Plant cell wall Composition
... be fungi, but structural and molecular evidence has led to their reclassification as heterokonts, related to autotrophic brown algae and diatoms. Unlike fungi, oomycetes typically possess cell walls of cellulose and glucans rather than chitin, although some genera (such as Achlya and Saprolegnia) d ...
... be fungi, but structural and molecular evidence has led to their reclassification as heterokonts, related to autotrophic brown algae and diatoms. Unlike fungi, oomycetes typically possess cell walls of cellulose and glucans rather than chitin, although some genera (such as Achlya and Saprolegnia) d ...
Evidence for Gal3p`s Cytoplasmic Location
... added at 2%, and the cells were incubated for two additional hours. Cell fractionation and nuclei enrichment were carried out using two independent protocols, one based on a sucrose gradient method (24, 48) and the other based on a Ficoll gradient method (2, 16). Both procedures gave similar results ...
... added at 2%, and the cells were incubated for two additional hours. Cell fractionation and nuclei enrichment were carried out using two independent protocols, one based on a sucrose gradient method (24, 48) and the other based on a Ficoll gradient method (2, 16). Both procedures gave similar results ...
Nod factor internalization and microtubular
... determinate nodules formed, for example, on the roots of siratro or soybean. In such nodules, meristematic activity is transient and the central cells differentiate almost simultaneously (Newcomb, 1981). As a result, round-shaped mature determinate nodules increase in size by cell enlargement and al ...
... determinate nodules formed, for example, on the roots of siratro or soybean. In such nodules, meristematic activity is transient and the central cells differentiate almost simultaneously (Newcomb, 1981). As a result, round-shaped mature determinate nodules increase in size by cell enlargement and al ...
File
... 2. A biologist conducts an experiment designed to determine whether a particular type of molecule is transported into cells by simple diffusion, facilitated diffusion, or active transport. He collects the following information: 1) The molecule is very small. 2) The molecule is polar. 3) The molecule ...
... 2. A biologist conducts an experiment designed to determine whether a particular type of molecule is transported into cells by simple diffusion, facilitated diffusion, or active transport. He collects the following information: 1) The molecule is very small. 2) The molecule is polar. 3) The molecule ...
rapid communication - AJP
... CD2AP and vinculin and found that the CD2AP-labeled spots do not colocalize with vinculin and that both proteins are clearly separated from each other (Fig. 3, g–i). Moreover, CD2AP is not found at the ends of actin stress fibers, but it shows overlapping expression with stress fiber-independent F-a ...
... CD2AP and vinculin and found that the CD2AP-labeled spots do not colocalize with vinculin and that both proteins are clearly separated from each other (Fig. 3, g–i). Moreover, CD2AP is not found at the ends of actin stress fibers, but it shows overlapping expression with stress fiber-independent F-a ...
Neurospora are haploid organisms that can reproduce asexually or
... colonies of different mating type A an a come into contact, their cell walls and nuclei fuse resulting in hypha with diploid nuclei. These structures produce fruiting buddies called perithecia and inside the perithecia the formation of the ascus will take place. These structures are all diploid with ...
... colonies of different mating type A an a come into contact, their cell walls and nuclei fuse resulting in hypha with diploid nuclei. These structures produce fruiting buddies called perithecia and inside the perithecia the formation of the ascus will take place. These structures are all diploid with ...
7-2 Eukaryotic Cell Structure
... Plants and some other organisms contain chloroplasts. Chloroplasts capture energy from sunlight and convert it into chemical energy in a process called photosynthesis. Slide 26 of 49 Copyright Pearson Prentice Hall ...
... Plants and some other organisms contain chloroplasts. Chloroplasts capture energy from sunlight and convert it into chemical energy in a process called photosynthesis. Slide 26 of 49 Copyright Pearson Prentice Hall ...
TR Worksheets
... of water and dissolved mineral ions. Vessels can be up to several metres long and are strengthened with lignin (in spiral, ring or net patterns), making them impermeable to water and giving them support. Pits in the walls enable water and solutes to pass through from one xylem element to another. Tr ...
... of water and dissolved mineral ions. Vessels can be up to several metres long and are strengthened with lignin (in spiral, ring or net patterns), making them impermeable to water and giving them support. Pits in the walls enable water and solutes to pass through from one xylem element to another. Tr ...
Chapter_12
... Time to traverse network depends on propagation delay, switching delay Assume propagation at two-thirds speed of light If source and destination on opposite sides of USA, propagation time ~ 48x10-3 seconds Given implicit congestion control, by the time dropped cell notification has reached sourc ...
... Time to traverse network depends on propagation delay, switching delay Assume propagation at two-thirds speed of light If source and destination on opposite sides of USA, propagation time ~ 48x10-3 seconds Given implicit congestion control, by the time dropped cell notification has reached sourc ...
Myofibrillogenesus in Skeletal Muscle Cells
... Figure 6A–B. Two different points of one region of a myotube transfected with a plasmid encoding YFP-alpha-actinin are shown. (A) The presence of premyofibrils (arrow) on the edge of this myotube can be seen. (B) The same live myotube is shown 1 hour later. The boxed area indicates an area where Z-bo ...
... Figure 6A–B. Two different points of one region of a myotube transfected with a plasmid encoding YFP-alpha-actinin are shown. (A) The presence of premyofibrils (arrow) on the edge of this myotube can be seen. (B) The same live myotube is shown 1 hour later. The boxed area indicates an area where Z-bo ...
A single-headed fission yeast myosin V transports actin in a
... of the amounts, and timeline of appearance, of many key proteins involved in this process (Pollard and Wu, 2010). Assembly and constriction of the contractile ring involves an actomyosin-based system. In fission yeast, this process requires two class II myosins (Myo2 and Myp2) and one class V myosin ...
... of the amounts, and timeline of appearance, of many key proteins involved in this process (Pollard and Wu, 2010). Assembly and constriction of the contractile ring involves an actomyosin-based system. In fission yeast, this process requires two class II myosins (Myo2 and Myp2) and one class V myosin ...
Attachment
... plastids, mitochondria, lysosomes, and Golgi complexes. Non-membrane-bound organelles, such as ribosomes and centrioles are also present in eukaryotic cells. Cells are small because as they get larger, their surface area to volume ratio becomes too small to bring in enough nutrients and get rid of e ...
... plastids, mitochondria, lysosomes, and Golgi complexes. Non-membrane-bound organelles, such as ribosomes and centrioles are also present in eukaryotic cells. Cells are small because as they get larger, their surface area to volume ratio becomes too small to bring in enough nutrients and get rid of e ...
Cell Structures Endoplasmic Reticulum
... Read RNA messages from nucleus to make proteins Site of Respiration. Makes ATP energy for the cell ...
... Read RNA messages from nucleus to make proteins Site of Respiration. Makes ATP energy for the cell ...
Glycoside Hydrolase Activities in Cell Walls of Sclerenchyma Cells
... signals from the recently formed secondary wall layers are shown with red arrows. Intensity profiles through the cell wall area, shown by the white arrows, are included to visualize the labeling patterns in the cell wall better. Bar = 50 μm. ...
... signals from the recently formed secondary wall layers are shown with red arrows. Intensity profiles through the cell wall area, shown by the white arrows, are included to visualize the labeling patterns in the cell wall better. Bar = 50 μm. ...
Cytoplasmic streaming
Cytoplasmic streaming, also called protoplasmic streaming and cyclosis, is the directed flow of cytosol (the liquid component of the cytoplasm) and organelles around large fungal and plant cells through the mediation of actin. This movement aids in the delivery of organelles, nutrients, metabolites, genetic information, and other materials to all parts of the cell. Cytoplasmic streaming occurs along actin filaments in the cytoskeleton of the cell.Cytoplasmic streaming was first discovered in the 1830s. The scientific breakthrough assisted scientists in developing an understanding of the different roles of cells and how they function as the basic operating systems of life.This process occurs through the operation of motor proteins called myosins.These proteins use energy of adenosine triphosphate (ATP) to act as a molecular motor, which slides along actin filaments. This works in a manner that tows the organelles and other cytoplasmic contents in the same direction. Myosin proteins consist of two conjoined proteins. If one protein remains attached to the substrate, the substance acted upon by the protein, such as a microfilament, has the ability to move organelles through the cytoplasm.The green alga genus Chara and other genera in the Division Charophyta, such as Coleochaete, are thought to be the closest relatives of land plants. These haploid organisms contain some of the largest plant cells on earth, a single cell of which can reach up to 10 cm in length. The large size of these cells demands an efficient means to distribute resources, which is enabled via cytoplasmic streaming.Cytoplasmic streaming is strongly dependent upon intracellular pH and temperature. It has been observed that the effect of temperature on cytoplasmic streaming created linear variance and dependence at different high temperatures in comparison to low temperatures. This process is complicated, with temperature alterations in the system increasing its efficiency, with other factors such as the transport of ions across the membrane being simultaneously affected. This is due to cells homeostasis depending upon active transport which may be affected at some critical temperatures.In plant cells, chloroplasts may be moved around with the stream, possibly to a position of optimum light absorption for photosynthesis. The rate of motion is usually affected by light exposure, temperature, and pH levels.In reference to pH, because actin and myosin are both proteins, strong dependence on pH is expected. The optimal pH at which cytoplasmic streaming is highest, is achieved at neutral pH and decreases at both low and high pH.The flow of cytoplasm may be stopped by:Adding Lugol's iodine solutionAdding Cytochalasin D (dissolved in dimethyl sulfoxide)↑ ↑ ↑ ↑ ↑ ↑