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Ở một loài thực vật, tính trạng màu sắc hoa do một cặp gen quy định, tính trạng hình dạng quả do một cặp gen khác quy định. Cho cây hoa đỏ, quả tròn thuần chủng giao phấn với cây hoa vàng, quả bầu dục thuần chủng (P), thu được F1 gồm 100% cây hoa đỏ, quả tròn. Cho các cây F1 tự thụ phấn, thu được F2 gồm 4 loại kiểu hình, trong đó cây hoa vàng, quả tròn chiếm tỉ lệ 16%. Biết rằng trong quá trình phát sinh giao tử đực và giao tử cái đều xảy ra hoán vị gen với tần số như nhau. Trong các kết luận sau, có bao nhiêu kết luận đúng với phép lai trên? (1) Theo lí thuyết, ở F2 có 10 loại kiểu gen. (2) Theo lí thuyết, ở F2 có 5 loại kiểu gen cùng quy định kiểu hình hoa đỏ, quả tròn. (3) Theo lí thuyết, ở F2 số cá thể có kiểu gen giống kiểu gen của F1 chiếm tỉ lệ 26%. (4) Theo lí thuyết, F1 xảy ra hoán vị gen với tần số 40%. (5) Theo lí thuyết, ở F2 số cá thể có kiểu gen quy định kiểu hình hoa đỏ, quả tròn dị hợp về một cặp gen chiếm tỉ lệ 24%.  (6) Theo lí thuyết, ở F2 có 2 loại kiểu gen cùng quy định kiểu hình hoa đỏ, quả bầu dục.

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Read the following passage and mark the letter A, B, C, or D on your answer sheet to indicate the correct word or phrase that best fits each of the numbered blanks from 23 to 27.           The story of gold is an adventure involving kings, queens, pirates, explorers, conquerors, and the native peoples they conquered. Throughout history, gold has woven a magic spell over those it touched. Gold is beautiful and rare; a soft shiny metal that can be moulded into many (23) _________. It has been used for money, jewelry, and to decorate special buildings such as palaces and places of worship. (24) _________ the precious metal was discovered, prospectors rushed to mine it, starting new cities and countries as they went. Gold and the people who love it have helped shape the world we live (25)   _________today. Gold is one of many elements, or substances that cannot be changed by normal chemical means, that are found in the Earth's crust. Gold has a warm, sunny colour and (26) _________ it does not react with air, water, and most chemicals, its shine never fades. In its natural (27) _________, gold is soft and easily shaped. When heated to 1,062 Celsius it melts and can be poured into moulds to form coins, gold bars, and other objects. Stories have been told, movies made and legends bom about the discovery of the world’s great gold deposits. It is a saga of dreams, greed, ambition and exploration. Điền vào số (26)

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Read the following passage and mark the letter A, B, C, or D on your answer sheet to indicate the correct word or phrase that best fits each of the numbered blanks from 23 to 27.           The story of gold is an adventure involving kings, queens, pirates, explorers, conquerors, and the native peoples they conquered. Throughout history, gold has woven a magic spell over those it touched. Gold is beautiful and rare; a soft shiny metal that can be moulded into many (23) _________. It has been used for money, jewelry, and to decorate special buildings such as palaces and places of worship. (24) _________ the precious metal was discovered, prospectors rushed to mine it, starting new cities and countries as they went. Gold and the people who love it have helped shape the world we live (25)   _________ today. Gold is one of many elements, or substances that cannot be changed by normal chemical means, that are found in the Earth's crust. Gold has a warm, sunny colour and (26) _________ it does not react with air, water, and most chemicals, its shine never fades. In its natural (27) _________, gold is soft and easily shaped. When heated to 1,062 Celsius it melts and can be poured into moulds to form coins, gold bars, and other objects. Stories have been told, movies made and legends bom about the discovery of the world’s great gold deposits. It is a saga of dreams, greed, ambition and exploration. Điền vào số (25)

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Read the following passage and mark the letter A, B, C, or D on your answer sheet to indicate the correct word or phrase that best fits each of the numbered blanks from 23 to 27.           The story of gold is an adventure involving kings, queens, pirates, explorers, conquerors, and the native peoples they conquered. Throughout history, gold has woven a magic spell over those it touched. Gold is beautiful and rare; a soft shiny metal that can be moulded into many (23) _________. It has been used for money, jewelry, and to decorate special buildings such as palaces and places of worship. (24) _________ the precious metal was discovered, prospectors rushed to mine it, starting new cities and countries as they went. Gold and the people who love it have helped shape the world we live (25)   _________today. Gold is one of many elements, or substances that cannot be changed by normal chemical means, that are found in the Earth's crust. Gold has a warm, sunny colour and (26) _________ it does not react with air, water, and most chemicals, its shine never fades. In its natural (27) _________, gold is soft and easily shaped. When heated to 1,062 Celsius it melts and can be poured into moulds to form coins, gold bars, and other objects. Stories have been told, movies made and legends bom about the discovery of the world’s great gold deposits. It is a saga of dreams, greed, ambition and exploration. Điền vào số (24)

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Read the following passage and mark the letter A, B, C, or D on your answer sheet to indicate the correct word or phrase that best fits each of the numbered blanks from 23 to 27.           The story of gold is an adventure involving kings, queens, pirates, explorers, conquerors, and the native peoples they conquered. Throughout history, gold has woven a magic spell over those it touched. Gold is beautiful and rare; a soft shiny metal that can be moulded into many (23) _________. It has been used for money, jewelry, and to decorate special buildings such as palaces and places of worship. (24) _________ the precious metal was discovered, prospectors rushed to mine it, starting new cities and countries as they went. Gold and the people who love it have helped shape the world we live (25)     _________ today. Gold is one of many elements, or substances that cannot be changed by normal chemical means, that are found in the Earth's crust. Gold has a warm, sunny colour and (26) _________ it does not react with air, water, and most chemicals, its shine never fades. In its natural (27) _________, gold is soft and easily shaped. When heated to 1,062 Celsius it melts and can be poured into moulds to form coins, gold bars, and other objects. Stories have been told, movies made and legends bom about the discovery of the world’s great gold deposits. It is a saga of dreams, greed, ambition and exploration. Điền vào số (23)

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