Вопрос школьника по предмету Биология
50Б!!!Установить взаимосвязи строения и функций
молекул РНК в клетке. Пожалуйста
Ответ учителя по предмету Биология
Ответ:Функции РНК
По выполнению функций выделя-ют несколько видов РНК.
Транспортная РНК (т-РНК) . Молекулы т-РНК самые короткие: они состоят всего из 80—100 нуклео-тидов. Молекулярная масса таких частиц равна 25—30 тыс. Транспортная РНК в основном содержится в цитоплазме клетки. Функция состоит в переносе аминокислот в рибосомы, к месту синтеза белка. Из общего содержания РНК клетки на долю т-РНК приходится около 10%.
Рибосомная РНК (р-РНК) . Это самые крупные РНК в их молекулы входит 3—5 тыс. нуклеотидов, соответственно их молекулярная масса достигает 1,0—1, 5 млн. Рибосомная РНК составляет существенную часть структуры рибосомы. Из общего содержания РНК в клетке на долю р-РНК приходится около 90%.
Информационная РНК (и-РНК) , или матричная (м-РНК) . Содержится в ядре и цитоплазме. Функция ее состоит в переносе информации о структуре белка от ДНК к месту синтеза белка в рибосомах. На долю и-РНК приходится примерно 0,5—1% от общего содержания РНК клетки.
Все виды РНК синтезируются на ДНК, которая служит своего рода матрицей.
Объяснение:
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