Magnetoreception — Магниторецепция

The magnetic field of the earth is an important tool for navigation among birds. 18 species of birds have a magnetic compass to aid them in their seasonal migration and home navigation. The magnetic compass was first described for European robins. Captive individuals of migrants become restless in their cages at the time of the year when their migration usually starts. They also preferred to stay at the side of the cage pointing to their migrating destination. This behavior was used to analyze the orientation of the birds in a laboratory where magnetic fields can be varied in a controllable manner. When the magnetic north was rotated by coil systems, while the field’s total intensity and inclination were held constant, the birds altered their directional preferences according to the change in the magnetic north. This behavior clearly indicates that the birds used the magnetic field for direction finding.

SkyEng
Общая оцен­ка: 5
Сто­и­мость обу­че­ния: От 700 р./урок
Скид­ки: Раз­лич­ные бону­сы и скид­ки
Режим обу­че­ния: Skype/Vimbox
Бес­плат­ный урок: Преду­смот­рен
Мето­ди­ка обу­че­ния: Окс­форд­ская
Онлайн тести­ро­ва­ние: Преду­смот­ре­но
Отзы­вы кли­ен­тов: (5/5)
Лите­ра­ту­ра: Онлайн биб­лио­те­ка
Адрес: study@skyeng.ru, skyeng.skype, 8 800 555–45-22
За: 593
Про­тив: 216

As a result of bird’s dependence on the earth magnetic field for navigation, they have been of particular interest for the study of magnetoreception. Species with magnetoreception functions contain internal chains of either single-domain (SD) magnetite or greigite that produce a magnetic moment large enough to rotate the cell into passive alignment with the geomagnetic field. When a magnetic pulse applied antiparallel to the magnetization direction causes the moment to reverse direction, making a bacterium swim south instead of north, which is a unique property of ferromagnetic material. Suggestions also have been made that deposits of superparamagnetic (SPM) magnetite detected in some animals may be involved in magnetoreception.

Общая оцен­ка: 5
Сто­и­мость обу­че­ния: От 600 руб/урок
Скид­ки: Раз­лич­ные бону­сы и скид­ки
Режим обу­че­ния: Онлайн
Бес­плат­ный урок: Преду­смот­рен
Мето­ди­ка обу­че­ния: Игро­вая и погру­же­ние в сре­ду
Онлайн тести­ро­ва­ние: Преду­смот­ре­но
Лите­ра­ту­ра: Онлайн биб­лио­те­ка
Адрес: info@englishdom.com +7 (499) 703 15 52
«Инглекс»
Общая оцен­ка: 5
Сто­и­мость обу­че­ния: От 590 руб/час
Скид­ки: Покуп­ка паке­тов заня­тий, при­гла­ше­ние дру­зей
Режим обу­че­ния: Онлайн
Бес­плат­ный урок: Преду­смот­рен
Мето­ди­ка обу­че­ния: Зави­сит от кур­са, опре­де­ля­ет­ся пре­по­да­ва­те­лем
Онлайн тести­ро­ва­ние: Преду­смот­ре­но
Отзы­вы кли­ен­тов: (5/5)
Лите­ра­ту­ра: -
Адрес: -
За: 487
Про­тив: 123

Birds appear to use information from the geomagnetic field in two ways; the first is for position determination while the second as a compass for direction finding. These probably involve separate receptor systems as the biophysical constraints of how both may function differently. In view of these findings, researchers found great interest in determining the existence of magnetic biomaterials in animals through behavioral studies.

In birds, magnetite was found in the head, particularly in the ethmoid region above the beak. The ophthalmic nerve, a branch of the nervous trigeminus, inverts these parts of the head. Electrophysiological recordings from this nerve and from the trigeminal ganglion of Bobolinks Dolichonyx oryzivorous revealed units that responded to changes in the intensity of the magnetic field. In some studies, treatment with a strong magnetic pulse had a considerable effect on the migratory orientation of Australian silvereyes, deflecting the bird’s headings from their natural migratory direction approximately 90 degrees towards the east for two days. Because the treatment with a strong magnetic pulse usually disorients the birds, it is thought that at least one receptor utilizes a magnetizable material such as magnetite. In a recent study, it was found that the effect of the magnetizing treatment can be abolished by blocking the ophthalmic branch of the trigeminal nerve, but the ability of the bird to select and maintain a certain direction was not affected. These results also support the hypothesis that a magnetizable material is a part of the magnetoreception system.

Лин­гуа­Лео
Общая оцен­ка: 5
Сто­и­мость обу­че­ния: 10–17$/курс
Скид­ки: Скид­ки при оформ­ле­нии годо­вой под­пис­ки и для посто­ян­ных поль­зо­ва­те­лей
Режим обу­че­ния: Онлайн
Бес­плат­ный урок: Преду­смот­рен
Мето­ди­ка обу­че­ния: Игро­вая
Онлайн тести­ро­ва­ние: Преду­смот­ре­но
Отзы­вы кли­ен­тов: (5/5)
Лите­ра­ту­ра: Онлайн биб­лио­те­ка
Адрес: 143026, г.Москва, «Скол­ко­во», Луго­вая ул., 4, стро­е­ние 8, info@lingualeo.com
За: 419
Про­тив: 158

If magnetite-containing cells are used in magnetoreception, it is reasonable to predict that they should be linked to magnetically responsive nerves. However, understanding the genetic basis of magnetite biomineralization will provide the needed molecular tools for testing the hypothesis of common descent, and for testing magnetite’s role in magnetoreception of all animal groups. The location and structure of the magnetoreceptors that transduce the magnetic information to the nervous system remain unknown mysteries to the interested researcher.

Many studies have been made to determine whether homing pigeons contain magnetic material in their bodies. Most of these studies aimed to prove the existence of such material through behavioral experiments carried on the pigeons. Some studies also proposed the idea of magnetic material influence being integrated by the ophthalmic nerve to guide the birds in their journey. The mechanism of how the pigeons since the variation in the earth magnetic field and how to use it as a navigational tool are not fully understood.
Models of how the birds can use the earth’s magnetic field have been discussed but weren’t related to the physiological actions. Lengthy researches and studies are the only way to unrevealing the mystery of the neurological mechanisms leading to the precise determination of destination observed in pigeons.

Puzzle English
Общая оцен­ка: 5
Сто­и­мость обу­че­ния: От 990 рублей/курс
Скид­ки: 7 дней бес­плат­но
Режим обу­че­ния: Онлайн
Бес­плат­ный урок: Преду­смот­рен
Мето­ди­ка обу­че­ния: Само­сто­я­тель­ное обу­че­ние
Онлайн тести­ро­ва­ние: Преду­смот­ре­но
Отзы­вы кли­ен­тов: (5/5)
Лите­ра­ту­ра: -
Адрес: -
За: 445
Про­тив: 113
SkyEng
Общая оцен­ка: 5
Сто­и­мость обу­че­ния: От 700 р./урок
Скид­ки: Раз­лич­ные бону­сы и скид­ки
Режим обу­че­ния: Skype/Vimbox
Бес­плат­ный урок: Преду­смот­рен
Мето­ди­ка обу­че­ния: Окс­форд­ская
Онлайн тести­ро­ва­ние: Преду­смот­ре­но
Отзы­вы кли­ен­тов: (5/5)
Лите­ра­ту­ра: Онлайн биб­лио­те­ка
Адрес: study@skyeng.ru, skyeng.skype, 8 800 555–45-22
За: 593
Про­тив: 216
Общая оцен­ка: 5
Сто­и­мость обу­че­ния: От 700 р./урок
Скид­ки: Раз­лич­ные бону­сы и скид­ки
Режим обу­че­ния: Skype/Vimbox
Бес­плат­ный урок: Преду­смот­рен
Мето­ди­ка обу­че­ния: Окс­форд­ская
Онлайн тести­ро­ва­ние: Преду­смот­ре­но
Лите­ра­ту­ра: Онлайн биб­лио­те­ка
Адрес: study@skyeng.ru, skyeng.skype, 8 800 555–45-22
Лин­гуа­Лео
Общая оцен­ка: 5
Сто­и­мость обу­че­ния: 10–17$/курс
Скид­ки: Скид­ки при оформ­ле­нии годо­вой под­пис­ки и для посто­ян­ных поль­зо­ва­те­лей
Режим обу­че­ния: Онлайн
Бес­плат­ный урок: Преду­смот­рен
Мето­ди­ка обу­че­ния: Игро­вая
Онлайн тести­ро­ва­ние: Преду­смот­ре­но
Отзы­вы кли­ен­тов: (5/5)
Лите­ра­ту­ра: Онлайн биб­лио­те­ка
Адрес: 143026, г.Москва, «Скол­ко­во», Луго­вая ул., 4, стро­е­ние 8, info@lingualeo.com
За: 419
Про­тив: 158

Под­пи­ши­тесь, и вы полу­чи­те доступ к бону­сам от школ и кур­сов англий­ско­го язы­ка!