zone of inhibition

Examples of zone of inhibition in the following topics:

• Kirby-Bauer Disk Susceptibility Test

  • A larger zone of inhibition around an antibiotic-containing disk indicates that the bacteria are more sensitive to the antibiotic in the disk.
  • KB tests are performed under standardized conditions and standard-sized zones of inhibition have been established for each antibiotic.
  • KB test results are usually reported as sensitive, intermediate, or resistant, based on the size of the zone of inhibition.
  • If the observed zone of inhibition is greater than or equal to the size of the standard zone, the microorganism is considered to be sensitive to the antibiotic.
  • Conversely, if the observed zone of inhibition is smaller than the standard size, the microorganism is considered to be resistant.

• Types of Root Systems and Zones of Growth

  • The root tip has three main zones: a zone of cell division, a zone of elongation, and a zone of maturation.
  • The root tip can be divided into three zones: a zone of cell division, a zone of elongation, and a zone of maturation .
  • All three zones are in approximately the first centimeter of the root tip.
  • A longitudinal view of the root reveals the zones of cell division, elongation, and maturation.
  • Describe the three zones of the root tip and summarize the role of each zone in root growth

• Growth of Bone

  • The epiphyseal plate is composed of four zones of cells and activity.
  • The longitudinal growth of bone is a result of cellular division in the proliferative zone along with the maturation of cells in the zone of maturation and hypertrophy.
  • After the zone of calcified matrix, there is the zone of ossification, which is actually part of the metaphysis .
  • The topmost layer of the epiphysis is the reserve zone.
  • The bottom-most row is the zone of ossification which is part of the metaphysis.

• Meristems

  • The central zone is located at the meristem summit, where a small group of slowly dividing cells can be found.
  • Cells of this zone have a stem cell function and are essential for meristem maintenance.
  • Surrounding the central zone is the peripheral zone.
  • The rate of cell division in the peripheral zone is higher than that of the central zone.
  • Each zone of the apical meristem has a particular function.

• Marine Biomes

  • Each zone has a distinct group of species adapted to the biotic and abiotic conditions particular to that zone.
  • This zone is an extremely variable environment because of tides.
  • The neritic zone extends from the intertidal zone to depths of about 200 m (or 650 ft) at the edge of the continental shelf.
  • The majority of organisms in the aphotic zone include sea cucumbers and other organisms that survive on the nutrients contained in the dead bodies of organisms in the photic zone.
  • There are a variety of invertebrates and fishes found in this zone, but the abyssal zone does not have plants due to the lack of light.

• Functions of the Cerebellum in Integrating Movements

  • The small amount of recurrence that does exist consists of mutual inhibition; there are no mutually excitatory circuits.
  • A module (a multizonal microcompartment in the terminology of Apps and Garwicz) consists of a small cluster of neurons in the inferior olivary nucleus, a set of long narrow strips of Purkinje cells in the cerebellar cortex (microzones), and a small cluster of neurons in one of the deep cerebellar nuclei.
  • This schematic illustration of the structure of zones and microzones in the cerebellum shows three levels of magnification.
  • These zones and microzones help explain the modular nature of the cerebellar function.
  • A "zone" is a longitudinally oriented strip of the cortex, and a "microzone" is a thin, longitudinally oriented portion of a zone.

• Adrenal Cortex

  • The adrenal cortex comprises three zones, or layers: Zona glomerulosa (outer), Zona fasciculata and Zona reticularis.
  • Aldosterone exerts its effects on the distal convoluted tubule and collecting duct of the kidney where it causes increased reabsorption of sodium and increased excretion of both potassium (by principal cells) and hydrogen ions (by intercalated cells of the collecting duct).
  • It increases blood glucose levels in response to stress, by inhibiting glucose uptake into muscle and fat cells
  • Testosterone : a hormone with a wide variety of effects, ranging from enhancing muscle mass and stimulation of cell growth to the development of the secondary sex characteristics.
  • Differentiate among the zones (and hormones produced) of the adrenal cortex

• Horizontal Communication

  • Horizontal communication is the flow of messages across individuals and groups on the same level of an organization.
  • Horizontal communication, also called lateral communication, involves the flow of messages between individuals and groups on the same level of an organization.
  • According to Professor Michael Papa, horizontal communication problems can occur because of territoriality, rivalry, specialization, and simple lack of motivation.
  • Lingering expectations from the old system can significantly inhibit the implementation of horizontal communication.
  • Finally, corporations that operate in different geographic locations, particularly internationally, may struggle with horizontal communication across time zones as the confront the barriers of local idioms, customs, and languages.

• Dendritic Cells

  • Langerhans cells of the epidermis) are located in main portals of entry of microbes (skin and gut epithelia).
  • Mature dendritic cells reside in the T cell zones of the lymph nodes, and in this location they display antigens to T cells.
  • Subsets of dendritic cells can be distinguished by the expression of cell surface markers.
  • Some may even inhibit T cell activation.
  • An example of this includes the interaction of the membrane proteins of the B7 family of the dendritic cell with a CD28 cell surface molecule present on the lymphocyte.

• The Phosphorus Cycle

  • This process is responsible for dead zones in lakes and at the mouths of many major rivers .
  • These zones can be caused by eutrophication, oil spills, dumping of toxic chemicals, and other human activities.
  • The number of dead zones has been increasing for several years; more than 400 of these zones were present as of 2008.
  • One of the worst dead zones is off the coast of the United States in the Gulf of Mexico, where fertilizer runoff from the Mississippi River basin has created a dead zone of over 8,463 square miles.
  • Worldwide, large dead zones are found in coastal areas of high population density.