Ở đậu Hà Lan, allele A quy định thân cao trội hoàn toàn so với allele a quy định thân thấp. Allele B quy định hoa đỏ trội hoàn toàn so với allele b quy định hoa trắng. Hai cặp gene này nằm trên 2 cặp nhiễm sắc thể tương đồng. Cho đậu thân cao, hoa đỏ dị hợp về 2 cặp gene tự thụ phấn thu được F1. Biết không xảy ra đột biến. Chọn ngẫu nhiên một cây thân cao, hoa đỏ ở thế hệ F1 cho tự thụ phấn. Xác suất thu được cây thân cao hoa đỏ ở thế hệ F2 là bao nhiêu?
Hãy suy nghĩ và trả lời câu hỏi trước khi xem đáp án
Theo bài: P: AaBb × AaBb → F1: 9A-B- : 3A-bb : 3aaB- : 1aabb
Xét từng tính trạng riêng rẽ: Aa × Aa → 1AA : 2Aa : 1aa
Bb × Bb → 1BB : 2Bb : 1bb
Tỉ lệ các cây thân cao, hoa đỏ ở F1 là: 4AaBb : 2AABb : 2AaBB : 1AABB
Lấy ngẫu nhiên cây thân cao, hoa đỏ tự thụ: A-B- × A-B-
→ Xác suất thu được cây thân cao hoa đỏ ở thế hệ F2 là: \(\dfrac{4}{9}\times \dfrac{9}{16}+\dfrac{2}{9}\times \dfrac{3}{4}+\dfrac{2}{9}\times \dfrac{3}{4}+\dfrac{1}{9}\times 1=\dfrac{25}{36}\)
Câu hỏi liên quan
Mark the letter A, B, C, or D on your answer sheet to indicate the best arrangement of utterances or sentences to make a meaningful exchange or text in each of the following questions from 13 to 17
At a florist’s …
a. A: How much are the roses?
b. B: Yes, they're on sale today.
c. B: Splendid. Will there be anything else?
d. B: $20 per dozen.
e. B: I'm sure your wife will love them.
f. A: I need some flowers for my wife. It's her birthday.
g. A: I'll take a dozen.
h. B: Very well. We have some fresh red roses.
i. A: No, the roses will be fine.
j. A: That sounds like a good deal.
Mark the letter A, B, C, or D on your answer sheet to indicate the underlined part that needs correction in each of the following questions.
They are having her house painted by a construction company.
Để thực hiện tìm kiếm bằng tiếng nói thì cần có gì?
Chủ thể nào sau đây đang tiến hành hoạt động sản xuất?
Read the following passage about the The Importance of Social Media in Modern Society and mark the letter A, B, C or D on your answer sheet to indicate the best answer to each of the following questions from 31 to 40.
In the 21st century, social media has become a crucial element of everyday life[I]. Platforms such as Facebook, Twitter, Instagram, and TikTok link individuals around the world, [IV]. Although some may critique social media for promoting negativity, it is important to acknowledge its numerous positive effects on society[III]. This essay will delve into the importance of social media, its influence on shaping public perception, and the challenges it poses.[II]
One of the primary benefits of social media is its ability to foster communication and connection. People can maintain relationships with friends and family, regardless of geographical barriers. This aspect is particularly vital for those who live far away from loved ones. For example, a student studying abroad can easily share their experiences with family through posts, photos, and video calls. Furthermore, social media enables individuals to connect with like-minded people and build communities around shared interests or causes. Activist groups, for instance, often use social media platforms to rally support for important issues, raising awareness and mobilizing action more efficiently than traditional methods.
Moreover, social media serves as a powerful tool for information dissemination. News spreads rapidly through these platforms, allowing individuals to stay informed about current events. During emergencies, such as natural disasters, social media can provide crucial information in real time, helping people stay safe and informed. However, this rapid dissemination of information also raises concerns about the accuracy and reliability of the content being shared. Misinformation can spread just as quickly as legitimate news, leading to confusion and mistrust.
Despite the challenges posed by misinformation, social media plays a significant role in shaping public opinion. People often turn to these platforms to voice their opinions and engage in discussions on various topics. For instance, political debates and social movements frequently gain traction through social media, allowing individuals to express their views and influence others. This democratization of discourse can empower marginalized voices and facilitate social change. However, it is crucial to approach online discussions critically, as echo chambers can form, reinforcing existing beliefs rather than encouraging open dialogue.
In conclusion, while social media presents challenges such as misinformation and polarized discussions, its positive contributions to communication, information dissemination, and social activism cannot be overlooked. As society continues to evolve, it is essential to harness the potential of social media while being mindful of its pitfalls. By promoting responsible use and critical thinking, we can maximize the benefits of social media and foster a more connected and informed society.
According to the paragraph 2, which of the following is NOT a benefits of social media?
Mỗi luận điểm nên được trình bày như thế nào trong một bài văn?
Loại tơ nào sau đây được đều chế bằng phản ứng trùng ngưng?
Các nước Mỹ Latinh hiện nay còn phụ thuộc nhiều nhất vào quốc gia nào sau đây?
Read the following passage and mark the letter A, B, C, or D on your answer sheet to indicate the best answer to each of the following questions from 31 to 40.
Who are you?
On 6 June 2011, the media reported the kidnapping of a female Syrian-American blogger called Amina Arraf. Regarded as a daring political rebel, the 35-year-old had gained popularity for her blogs protesting the lack of freedom in Syria. Yet, only two days later, it was discovered that Amina had never existed. She was a fictional character created by Tom MacMaster, a forty-year-old American PhD student at the University of Edinburgh.
MacMaster's invention is an example of sock puppetry: the use of false identities to deceive others. (I). The false identity is known as a sock puppet, and its creator, a puppet master. (II). MacMaster created Amina to express his views on Middle Eastern affairs without offending other Americans. (III). Writing as Amina gave him the authority to say what he wanted. (IV).
At the turn of the millennium, Debbie Swenson created Kaycee Nicole, a fictional teenage girl suffering from terminal cancer. Her blog, Living Colours, described Kaycee’s struggle, attracting millions of readers. When Kaycee 'died' on 14 May 2001, her fans were devastated. Their distress turned to anger when they discovered that Kaycee was not real. Swenson had developed the character to gain attention and sympathy.
While Amina and Kaycee were used to meet their creators' needs, other identities have been invented for profit. American gun advocate John Lott made up a fake student, Mary Rosh, to defend his writing online and give him positive reviews. Mystery writer RJ Ellory fabricated a team of sock puppets to praise his own books and tear into those of his rivals. British historian Orlando Figes lost credibility when he had to publicly apologise for doing the same.
Yet none of these stories compare to large-scale sock puppetry today. The New York City Police Department has false identities on social media to catch criminals. The US military is believed to use sock puppets to track potential terrorists. It is clear that the internet is a minefield today and we all have to step very carefully in order not to get hurt.
According to the passage, which of the following statements is TRUE?
Hàm số \(y = {\log _a}x\left( {a > 0,a \ne 1} \right)\) đồng biến trên \(\left( {0; + \infty } \right)\) với giá trị nào của a dưới đây?
CHỦ ĐỀ: THẾ GIỚI TUYỆT ĐẸP…
(Tham khảo bài văn của chủ đề trong đường link dưới đây ở trang 21)
https://tvsthpt.dlib.vn/app/doc-sach-ebook/d02db18272fe
Và trả lời câu hỏi sau:
Hoàn thành câu hỏi bằng cách chọn đáp án Đúng hoặc Sai.
Những hormone thực vật nào sau đây thuộc nhóm kìm hãm sự sinh trưởng?
Các cấp độ tổ chức sống tạo nên hệ tiêu hóa trong cơ thể con người là
Read the following passage and mark the letter A, B, C, or D on your answer sheet to indicate the best answer to each of the following questions from 23 to 30.
Vietnamese Women’s Achievements
Women have always played an important role in Vietnam’s history. Some fight for their country, some inspire others, and some make positive changes to society. Their contributions have shaped the nation in various ways, leaving a lasting impact on culture, politics, and the arts.
Trưng Trắc and Trưng Nhị are famous examples of women who fought for their country’s freedom. Known in Vietnamese as “Hai Bà Trưng,” the Trưng sisters successfully led their people in a rebellion against foreign invaders in 40 A.D. After their victory, they ruled the country for three years, demonstrating remarkable leadership and bravery. As the first female rulers of Vietnam, the Trưng sisters have become symbols of patriotism and resilience. Their significance is even greater considering that Vietnamese women at the time had very limited access to education and politics. Their story continues to inspire generations.
Sương Nguyệt Anh is another example of an influential Vietnamese woman. As the daughter of the patriotic poet Nguyễn Đình Chiểu, she mastered literature from a young age. She worked as a teacher before becoming the editor-in-chief of Nữ Giới Chung, the first women’s newspaper in Sài Gòn, in 1918. As the first female editor in Vietnam, she made significant contributions to the press, feminism, and poetry. Through her work, she promoted women’s rights and encouraged female empowerment.
A third example is Điềm Phùng Thị. She graduated from Hà Nội Medical University in 1946 and earned a PhD in dentistry in France in 1954. However, she later pursued a career in sculpture, creating artworks that reflected her love for Vietnam. She exhibited her work throughout Europe and became the first female Vietnamese member of the European Academy of Arts and Sciences in 1992. Her name was later recorded in the Larousse Dictionary of Painters, recognizing her as a remarkable artist.
In which paragraph does the passage mention the first female rulers of Vietnam?
Provide the correct form of the verb in brackets.
Theo quy định pháp luật, công dân có thể thực hiện quyền khiếu nại trong tình huống nào sau đây?
Nội dung hiến pháp bao gồm những gì?
Tập A={1;2;3;4;5;6} có bao nhiêu tập hợp con có đúng hai phần tử?
Hoạt động khai thác khoáng sản ở Cộng hòa Nam Phi diễn ra chủ yếu ở đâu?
Cuối thế kỉ XIX, quốc gia Đông Nam Á không bị chủ nghĩa thực dân xâm lược là