** Cho 6 cặp alen nằm trên 6 cặp NST thường khác nhau gồm Aa, Bb, Cc, Dd, Ee, Gg.

Bố đồng hợp 2 cặp gen, dị hợp 4 cặp gen, còn mẹ đồng hợp 3 cặp gen, dị hợp 2 cặp gen. Kiểu gen của cặp bố mẹ là một trong số bao nhiêu phép lai có thể xảy ra?

** Ở một loài thực vật, gen A quy định tính trạng cây cao; gen a quy định tính trạng cây thấp; gen B quy định quả tròn; gen b quy định quả bầu; gen D quy định quả to; d quy định quả nhỏ. Quá trình giảm phân hình thành giao tử có xảy ra hoán vị gen với tần số 20%.

Khi lai hai cây cao, quả tròn có kiểu gen với cây cao, quả bầu có kiểu gen tạo được số loại tổ hợp giao tử là:

** Ở gà, gen A quy định lông đốm, a quy định lông đen liên kết trên NST giới tính X; B quy định mào to, b quy định mào nhỏ nằm trên NST thường.

Phép lai không thể cho gà mái lông đốm, mào nhỏ là:

** Ở ruồi giấm, gen W qui định tính trạng mắt đỏ, gen w qui định tính trạng mắt trắng, nằm trên nhiễm sắc thể giới tính X, không có alen tương ứng trên Y.

Khi lai ruồi cái mắt trắng với ruồi đực mắt đỏ được F₁ với tỉ lệ kiểu hình là:

** Biết: A: Quả dài; a: Quả ngắn; B: Quả ngọt; b: Quả chua. Hai cặp gen cùng nằm trên 1 cặp NST tương đồng.

Đem F₁ dị hợp 2 cặp gen giao phối với cây khác chưa biết kiểu gen thu được F₂ có 9 cây quả ngắn, ngọt : 6 quả dài, ngọt : 4 quả dài, chua : 1 quả ngắn, chua. Kiểu gen của 2 cá thể và tần số hoán vị gen là:

** Ở gà, gen A quy định lông đốm, a quy định lông đen liên kết trên NST giới tính X; B quy định mào to, b quy định mào nhỏ nằm trên NST thường.

Số kiểu gen có thể có của loài khi xét cả 2 cặp tính trạng trên:

** Cho biết AA: quả tròn; Aa: quả bầu, aa: quả dài; B: hạt vàng, b: hạt trắng; D: hạt to, d: hạt nhỏ. Cho thế hệ P có kiểu gen AabbDd x aaBbDd.

Xác suất xuất hiện ở F₁ loại kiểu hình quả bầu, hạt vàng, to bằng:

Thế nào là tính trạng tương phản?

Khi đề cập đến định luật phân li độc lập kèm theo điều kiện nghiệm đúng của nó, điều nào sau đây sai?

1. Biến dị tổ hợp xuất hiện ở thế hệ sau là sự sểp xếp các tính trạng có sẵn ở P nhưng theo trật tự khác.
2. Kết quả tự thụ xuất hiện bao nhiêu kiểu hình thì khi lai phân tích cá thể đó cũng sẽ xuất hiện bấy nhiêu kiểu hình.
3. Bố mẹ khác nhau n cặp gen thì số phép lai tương đương là 2ⁿ.
4. Lai càng nhiều cặp tính trạng sẽ thu được số biến dị tổ hợp càng lớn.

Phương án đúng là:

Nội dung nào sau đây đúng?

** Cho 6 cặp alen nằm trên 6 cặp NST thường khác nhau gồm Aa, Bb, Cc, Dd, Ee, Gg.

Bố đồng hợp 2 cặp gen, dị hợp 4 cặp gen, còn mẹ đồng hợp 3 cặp gen, dị hợp 2 cặp gen. Kiểu gen của cặp bố mẹ là một trong số bao nhiêu phép lai có thể xảy ra?

Read the following passage and choose the letter A, B, C, or D on your answer sheet to indicate the correct answer to each of the questions:

Many flowering plants woo insect pollinators and gently direct them to their most fertile blossoms by changing the color of individual flowers from day to day. Through color cues, the plant signals to the insect that it would be better off visiting one flower on its bush than another. The particular hue tells the pollinator that the flower is full of far more pollen than are neighboring blooms. That nectar-rich flower also happens to be fertile and ready to disperse its pollen or to receive pollen the insect has picked up from another flower. Plants do not have to spend precious resources maintaining reservoirs of nectar in all their flowers. Thus, the color-coded communication system benefits both plants and insects. For example, on the lantana plant, a flower starts out on the first day as yellow, when it is rich with pollen and nectar. Influenced by an as-yet-unidentified environmental signal, the flower changes color by triggering the production of the pigment anthromyacin. It turns orange on the second day and red on the third. By the third day, it has no pollen to offer insects and is no longer fertile. On any given lantana bush, only 10 to 15 per cent of the blossoms are likely to be yellow and fertile. But in tests measuring the responsiveness of butterflies, it was discovered that the insects visited the yellow flowers at least 100 times more than would be expected from haphazard visitation. Experiments with paper flowers and painted flowers demonstrated that the butterflies were responding to color cues rather than, say, the scent of the nectar. In other types of plants, blossoms change from white to red, others from yellow to red, and so on. These color changes have been observed in some 74 families of plants.

Question: The word “hue” is closet in meaning to_______         

Read the following passage and choose the letter A, B, C, or D on your answer sheet to indicate the correct answer to each of the questions:

Many flowering plants woo insect pollinators and gently direct them to their most fertile blossoms by changing the color of individual flowers from day to day. Through color cues, the plant signals to the insect that it would be better off visiting one flower on its bush than another. The particular hue tells the pollinator that the flower is full of far more pollen than are neighboring blooms. That nectar-rich flower also happens to be fertile and ready to disperse its pollen or to receive pollen the insect has picked up from another flower. Plants do not have to spend precious resources maintaining reservoirs of nectar in all their flowers. Thus, the color-coded communication system benefits both plants and insects. For example, on the lantana plant, a flower starts out on the first day as yellow, when it is rich with pollen and nectar. Influenced by an as-yet-unidentified environmental signal, the flower changes color by triggering the production of the pigment anthromyacin. It turns orange on the second day and red on the third. By the third day, it has no pollen to offer insects and is no longer fertile. On any given lantana bush, only 10 to 15 per cent of the blossoms are likely to be yellow and fertile. But in tests measuring the responsiveness of butterflies, it was discovered that the insects visited the yellow flowers at least 100 times more than would be expected from haphazard visitation. Experiments with paper flowers and painted flowers demonstrated that the butterflies were responding to color cues rather than, say, the scent of the nectar. In other types of plants, blossoms change from white to red, others from yellow to red, and so on. These color changes have been observed in some 74 families of plants.

Question: The word “it” refers to_______         

Read the following passage and choose the letter A, B, C, or D on your answer sheet to indicate the correct answer to each of the questions:

Many flowering plants woo insect pollinators and gently direct them to their most fertile blossoms by changing the color of individual flowers from day to day. Through color cues, the plant signals to the insect that it would be better off visiting one flower on its bush than another. The particular hue tells the pollinator that the flower is full of far more pollen than are neighboring blooms. That nectar-rich flower also happens to be fertile and ready to disperse its pollen or to receive pollen the insect has picked up from another flower. Plants do not have to spend precious resources maintaining reservoirs of nectar in all their flowers. Thus, the color-coded communication system benefits both plants and insects. For example, on the lantana plant, a flower starts out on the first day as yellow, when it is rich with pollen and nectar. Influenced by an as-yet-unidentified environmental signal, the flower changes color by triggering the production of the pigment anthromyacin. It turns orange on the second day and red on the third. By the third day, it has no pollen to offer insects and is no longer fertile. On any given lantana bush, only 10 to 15 per cent of the blossoms are likely to be yellow and fertile. But in tests measuring the responsiveness of butterflies, it was discovered that the insects visited the yellow flowers at least 100 times more than would be expected from haphazard visitation. Experiments with paper flowers and painted flowers demonstrated that the butterflies were responding to color cues rather than, say, the scent of the nectar. In other types of plants, blossoms change from white to red, others from yellow to red, and so on. These color changes have been observed in some 74 families of plants.

Question: The word “triggering” is closest in meaning to_________         

Read the following passage and choose the letter A, B, C, or D on your answer sheet to indicate the correct answer to each of the questions:

Many flowering plants woo insect pollinators and gently direct them to their most fertile blossoms by changing the color of individual flowers from day to day. Through color cues, the plant signals to the insect that it would be better off visiting one flower on its bush than another. The particular hue tells the pollinator that the flower is full of far more pollen than are neighboring blooms. That nectar-rich flower also happens to be fertile and ready to disperse its pollen or to receive pollen the insect has picked up from another flower. Plants do not have to spend precious resources maintaining reservoirs of nectar in all their flowers. Thus, the color-coded communication system benefits both plants and insects. For example, on the lantana plant, a flower starts out on the first day as yellow, when it is rich with pollen and nectar. Influenced by an as-yet-unidentified environmental signal, the flower changes color by triggering the production of the pigment anthromyacin. It turns orange on the second day and red on the third. By the third day, it has no pollen to offer insects and is no longer fertile. On any given lantana bush, only 10 to 15 per cent of the blossoms are likely to be yellow and fertile. But in tests measuring the responsiveness of butterflies, it was discovered that the insects visited the yellow flowers at least 100 times more than would be expected from haphazard visitation. Experiments with paper flowers and painted flowers demonstrated that the butterflies were responding to color cues rather than, say, the scent of the nectar. In other types of plants, blossoms change from white to red, others from yellow to red, and so on. These color changes have been observed in some 74 families of plants.

Question: Which of the following describes the sequence of color changes that lantana blossom undergo?         

Read the following passage and choose the letter A, B, C, or D on your answer sheet to indicate the correct answer to each of the questions:

Many flowering plants woo insect pollinators and gently direct them to their most fertile blossoms by changing the color of individual flowers from day to day. Through color cues, the plant signals to the insect that it would be better off visiting one flower on its bush than another. The particular hue tells the pollinator that the flower is full of far more pollen than are neighboring blooms. That nectar-rich flower also happens to be fertile and ready to disperse its pollen or to receive pollen the insect has picked up from another flower. Plants do not have to spend precious resources maintaining reservoirs of nectar in all their flowers. Thus, the color-coded communication system benefits both plants and insects. For example, on the lantana plant, a flower starts out on the first day as yellow, when it is rich with pollen and nectar. Influenced by an as-yet-unidentified environmental signal, the flower changes color by triggering the production of the pigment anthromyacin. It turns orange on the second day and red on the third. By the third day, it has no pollen to offer insects and is no longer fertile. On any given lantana bush, only 10 to 15 per cent of the blossoms are likely to be yellow and fertile. But in tests measuring the responsiveness of butterflies, it was discovered that the insects visited the yellow flowers at least 100 times more than would be expected from haphazard visitation. Experiments with paper flowers and painted flowers demonstrated that the butterflies were responding to color cues rather than, say, the scent of the nectar. In other types of plants, blossoms change from white to red, others from yellow to red, and so on. These color changes have been observed in some 74 families of plants.

Question: The word “haphazard” is closest in meaning to which of the following?             

Read the following passage and choose the letter A, B, C, or D on your answer sheet to indicate the correct answer to each of the questions:

Many flowering plants woo insect pollinators and gently direct them to their most fertile blossoms by changing the color of individual flowers from day to day. Through color cues, the plant signals to the insect that it would be better off visiting one flower on its bush than another. The particular hue tells the pollinator that the flower is full of far more pollen than are neighboring blooms. That nectar-rich flower also happens to be fertile and ready to disperse its pollen or to receive pollen the insect has picked up from another flower. Plants do not have to spend precious resources maintaining reservoirs of nectar in all their flowers. Thus, the color-coded communication system benefits both plants and insects. For example, on the lantana plant, a flower starts out on the first day as yellow, when it is rich with pollen and nectar. Influenced by an as-yet-unidentified environmental signal, the flower changes color by triggering the production of the pigment anthromyacin. It turns orange on the second day and red on the third. By the third day, it has no pollen to offer insects and is no longer fertile. On any given lantana bush, only 10 to 15 per cent of the blossoms are likely to be yellow and fertile. But in tests measuring the responsiveness of butterflies, it was discovered that the insects visited the yellow flowers at least 100 times more than would be expected from haphazard visitation. Experiments with paper flowers and painted flowers demonstrated that the butterflies were responding to color cues rather than, say, the scent of the nectar. In other types of plants, blossoms change from white to red, others from yellow to red, and so on. These color changes have been observed in some 74 families of plants.

Question: The passage implies that insects would be most attracted to lantana blossoms_______         

Read the following passage and mark the letter A, B, C, or D on your answer sheet to indicate the correct answer to each of the questions:

During the 19th century, women in the U.S organized and participated in a large number of reform movements, including movements to reorganize the prison system, improve education, ban the sale of alcohol, and most importantly to free slaves. Some women saw similarities in the social status of women and slaves. Women like Elizabeth Cady Stanton and Lucy Stone were feminists and abolitionists who supported the rights of both women and blacks. A number of male abolitionists, including William Lloyd Garrison and Wendell Phillips also supported the rights of women to speak and participate equally with men in anti-slavery activities. Probably more than any other movement, abolitionism offered women a previously denied entry into politics. They became involved primarily in order to better their living conditions and the conditions of others. When the Civil war ended in 1865, the 14th, and 15th, Amendments to the Constitution adopted in 1868 and 1870 granted citizenship and suffrage to blacks but not to women. Discouraged but resolved, feminists influenced more and more women to demand the right to vote. In 1869, the Wyoming Territory had yielded to demands by feminists, but eastern states resisted more stubbornly than ever before. A woman's suffrage bill had been presented to every Congress since 1878 but it continually failed to pass until 1920, when the 19th Amendment granted women the right to vote.

Question 39: What is the topic of the passage?         

Read the following passage and mark the letter A, B, C, or D on your answer sheet to indicate the correct answer to each of the questions:

During the 19th century, women in the U.S organized and participated in a large number of reform movements, including movements to reorganize the prison system, improve education, ban the sale of alcohol, and most importantly to free slaves. Some women saw similarities in the social status of women and slaves. Women like Elizabeth Cady Stanton and Lucy Stone were feminists and abolitionists who supported the rights of both women and blacks. A number of male abolitionists, including William Lloyd Garrison and Wendell Phillips also supported the rights of women to speak and participate equally with men in anti-slavery activities. Probably more than any other movement, abolitionism offered women a previously denied entry into politics. They became involved primarily in order to better their living conditions and the conditions of others. When the Civil war ended in 1865, the 14th, and 15th, Amendments to the Constitution adopted in 1868 and 1870 granted citizenship and suffrage to blacks but not to women. Discouraged but resolved, feminists influenced more and more women to demand the right to vote. In 1869, the Wyoming Territory had yielded to demands by feminists, but eastern states resisted more stubbornly than ever before. A woman's suffrage bill had been presented to every Congress since 1878 but it continually failed to pass until 1920, when the 19th Amendment granted women the right to vote.

Question 38: What is not among the reformation movements of women?             

Read the following passage and mark the letter A, B, C, or D on your answer sheet to indicate the correct answer to each of the questions:

During the 19th century, women in the U.S organized and participated in a large number of reform movements, including movements to reorganize the prison system, improve education, ban the sale of alcohol, and most importantly to free slaves. Some women saw similarities in the social status of women and slaves. Women like Elizabeth Cady Stanton and Lucy Stone were feminists and abolitionists who supported the rights of both women and blacks. A number of male abolitionists, including William Lloyd Garrison and Wendell Phillips also supported the rights of women to speak and participate equally with men in anti-slavery activities. Probably more than any other movement, abolitionism offered women a previously denied entry into politics. They became involved primarily in order to better their living conditions and the conditions of others. When the Civil war ended in 1865, the 14th, and 15th, Amendments to the Constitution adopted in 1868 and 1870 granted citizenship and suffrage to blacks but not to women. Discouraged but resolved, feminists influenced more and more women to demand the right to vote. In 1869, the Wyoming Territory had yielded to demands by feminists, but eastern states resisted more stubbornly than ever before. A woman's suffrage bill had been presented to every Congress since 1878 but it continually failed to pass until 1920, when the 19th Amendment granted women the right to vote.

 Question 37: What cannot be inferred from the passage?         

Read the following passage and mark the letter A, B, C, or D on your answer sheet to indicate the correct answer to each of the questions:

During the 19th century, women in the U.S organized and participated in a large number of reform movements, including movements to reorganize the prison system, improve education, ban the sale of alcohol, and most importantly to free slaves. Some women saw similarities in the social status of women and slaves. Women like Elizabeth Cady Stanton and Lucy Stone were feminists and abolitionists who supported the rights of both women and blacks. A number of male abolitionists, including William Lloyd Garrison and Wendell Phillips also supported the rights of women to speak and participate equally with men in anti-slavery activities. Probably more than any other movement, abolitionism offered women a previously denied entry into politics. They became involved primarily in order to better their living conditions and the conditions of others. When the Civil war ended in 1865, the 14th, and 15th, Amendments to the Constitution adopted in 1868 and 1870 granted citizenship and suffrage to blacks but not to women. Discouraged but resolved, feminists influenced more and more women to demand the right to vote. In 1869, the Wyoming Territory had yielded to demands by feminists, but eastern states resisted more stubbornly than ever before. A woman's suffrage bill had been presented to every Congress since 1878 but it continually failed to pass until 1920, when the 19th Amendment granted women the right to vote.

Question 36: What does the 19th Amendment guarantee?