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分類侷限、有一位老先生、侷限、1000060365..、富水公司、Wing、郵局英文外勤、Song、Wong、Wong、

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八、In 1888, German agricultural chemists Hermann Hellriegel and Hermann Wilfarth discovered that root nodules can convert nitrogen from the air into ammonia. Root nodules are specialized structures formed by leguminous plants to facilitate nitrogen fixation by nitrogen-fixing bacteria. Certain species of cyanobacteria, such as Anabaena spp.(念珠藻), can also perform nitrogen fixation, but they do so through heterocysts instead of forming root nodules. As a result, cyanobacteria like Anabaena can carry out nitrogen fixation independently and live autonomously. (1) Why do symbiotic rhizobium bacteria in legumes' roots need to carry out nitrogen fixation? (2) Why can heterocysts of cyanobacteria perform nitrogen fixation independently? 10%
t ㆍWater can diffuse across the lipid bilayer membrane via simple diffusion and facilitate diffusion. Is the movement of water with facilitate diffusion always faster than that with simple diffusion? Yes, or not? And describe the mechanisms.10%
六ㆍPlease describe the differences between "action potential" and ''nerve impulse". And try to design a plan using proper statements and sketch draws for high school students. 10% m3m4
一、雙互換率與三點試交法16%
西元2000年，在國際的通力合作下，人類終於完成第一個人類基因體定序，一切都歸功於PCR技術、定序方法等現代生物科技的卓越進展。但在這些生物技術尚未發明之前，人類要如何明白染色體上基因之間的位置關係呢？
由於莫甘的研究，使科學家認識到基因之間具有連鎖的關係，而連鎖的基因可能發生互換。當我們要研究三個基因之間位置關係的時候，我們可以利用三點試交，分別測定出三個基因之間的互換率，再推想出三個基因之間最合理的排列方式。但是實驗結果往往發現這遺傳圖譜的單位—分莫甘的加成性往往差強人意。深入探討之後，發現原來是雙互換的發生，導致分莫甘的加成性有了些許的偏差。請回答下列題目：

【題組】
1.下列關於研究雙互換率的材料選取的敘述,何者正確?(2分)(A)可選取豌豆的高矮莖、花色、豆莢飽滿與否三個性狀進行(B)可選取沒有多餘質體(plasmid)干擾的模式大腸桿菌進行研究(C)可選取兩種純系的黑腹果蠅的雜交子代再利用試交進行研究(D)可選取典型蜜蜂蜂巢內的工蜂和雄蜂利用反交後進行研究
319. A company is marketing an investment opportunity to four potential customers. The company believes that its probability of making a sale is 0.7 for each of the first three customers but that it is only 0.2 for the fourth customer. The customers' purchases are independent of one another. Calculate the probability that at most two customers purchase the investment. (A) 0.18 (B) 0.39 (C) 0.57 (D) 0.71 (E) 0.82
318. Data on a certain pregnancy test show that a pregnant woman will test negative or not pregnant 10% of the time, while a non-pregnant woman will test positive 20% of the time. Thirty percent of the women who take the test are pregnant. Calculate the probability that a woman is pregnant given that her test outcome is positive. (A) 0.18 (B) 0.30 (C) 0.66 (D) 0.82 (E) 0.90

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