47. The word “intricate” in Paragraph 6 could be best replaced by which of the following?
(A) modest
(B) complex
(C) uniform
(D) straightforward
答案:登入後查看
統計: A(10), B(222), C(28), D(31), E(0) #2910952
統計: A(10), B(222), C(28), D(31), E(0) #2910952
詳解 (共 3 筆)
#6098533
The word “intricate” in Paragraph 6 could be best replaced by which of the following?
錯綜複雜的;複雜精細的;難理解的;難解決的
(A) modest 謙虛的;適中的; 不多的; 有限的
(B) complex 複雜的,錯綜複雜的;難懂的
(C) uniform 相同的;一律的
(D) straightforward 簡單的, 容易理解的, 誠實的
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#7259037
With every whiff you take as you walk by a bakery, a cloud of chemicals comes swirling up your nose. Identifying the smell as freshly baked bread is a complicated process. But, compared to the other senses, the sense of smell was often underappreciated. Recently, scientists studying olfaction have shed new light on how our sense of smell works and provided compelling evidence that it’s more sophisticated than previously thought.
嗅覺——被低估的感官
當您走過一家麵包店時,您吸入的每一口氣都會讓一團化學物質旋轉著湧入您的鼻子。將這種氣味識別為新鮮出爐的麵包是一個複雜的過程。然而,與其他感官相比,嗅覺通常被低估了。最近,研究嗅覺的科學家們對我們的嗅覺如何運作提供了新的見解,並提供了令人信服的證據,證明它比以前認為的要複雜得多。
In a recent survey of 7,000 young people around the world, about half of those between the age of 16 and 30 said that they would rather lose their sense of smell than give up access to technology like laptops or cell phones. So, what do we know about the sense of smell?
在最近一項對全球 7,000 名年輕人進行的調查中,大約一半年齡在 16 至 30 歲之間的人表示,他們寧願失去嗅覺,也不願放棄使用筆記型電腦或手機等技術。那麼,我們對嗅覺了解多少呢?
在最近一項對全球 7,000 名年輕人進行的調查中,大約一半年齡在 16 至 30 歲之間的人表示,他們寧願失去嗅覺,也不願放棄使用筆記型電腦或手機等技術。那麼,我們對嗅覺了解多少呢?
Smell begins at the back of nose, where millions of sensory neurons lie in a strip of tissue called the olfactory epithelium. The tips of these cells contain proteins called receptors that bind odor molecules. The receptors are like locks and the keys to open these locks are the odor molecules that float past, explains Leslie Vosshall, a scientist who studies olfaction at Rockefeller University.
嗅覺始於鼻腔後部,數百萬個感覺神經元位於一條名為嗅上皮(olfactory epithelium)的組織帶中。這些細胞的尖端含有稱為受體(receptors)的蛋白質,它們與氣味分子結合。研究嗅覺的洛克菲勒大學科學家萊斯利·沃斯霍爾(Leslie Vosshall)解釋說,受體就像鎖,而打開這些鎖的鑰匙就是漂浮而過的氣味分子。
嗅覺始於鼻腔後部,數百萬個感覺神經元位於一條名為嗅上皮(olfactory epithelium)的組織帶中。這些細胞的尖端含有稱為受體(receptors)的蛋白質,它們與氣味分子結合。研究嗅覺的洛克菲勒大學科學家萊斯利·沃斯霍爾(Leslie Vosshall)解釋說,受體就像鎖,而打開這些鎖的鑰匙就是漂浮而過的氣味分子。
People have about 450 different types of olfactory receptors. Each receptor can be activated by many different odor molecules, and each odor molecule can activate several different types of receptors. However, the forces that bind receptors and odor molecules can vary greatly in strength, so that some interactions are better “fits” than others.
人類擁有大約 450 種不同類型的嗅覺受體。每種受體可以被許多不同的氣味分子激活,而每個氣味分子也可以激活幾種不同類型的受體。然而,受體和氣味分子之間結合的力道強度可能差異很大,因此有些相互作用比其他相互作用更「契合」。
“Think of a lock that can be opened by 10 different keys. Two of the keys are a perfect fit and open the door easily. The other eight don’t fit as well, and it takes more jiggling to get the door open,” explains Vosshall.
沃斯霍爾解釋說:「想像一個可以被 10 把不同鑰匙打開的鎖。其中兩把鑰匙完全契合,可以輕鬆打開門。另外八把鑰匙不太適合,需要更多的晃動才能打開門。」
The complexity of receptors and their interactions with odor molecules are what allow us to detect a wide variety of smells. And what we think of as a single smell is actually a combination of many odor molecules acting on a variety of receptors, creating an intricate neural code that we can identify as the scent of a rose or freshly-cut grass.
受體的複雜性及其與氣味分子的相互作用,使我們能夠檢測到各種各樣的氣味。而我們認為的單一氣味,實際上是許多氣味分子作用於各種受體、創造出一個錯綜複雜的神經代碼的組合,我們可以將其識別為玫瑰或剛割下的草的氣味。
受體的複雜性及其與氣味分子的相互作用,使我們能夠檢測到各種各樣的氣味。而我們認為的單一氣味,實際上是許多氣味分子作用於各種受體、創造出一個錯綜複雜的神經代碼的組合,我們可以將其識別為玫瑰或剛割下的草的氣味。
This neural code begins with the nose’s sensory neurons. Once an odor molecule binds to a receptor, it initiates an electrical signal that travels from the sensory neurons to the olfactory bulb, a structure at the base of the forebrain that relays the signal to other brain areas for additional processing.
這種神經代碼始於鼻子的感覺神經元。一旦氣味分子與受體結合,它就會啟動一個電信號,該信號從感覺神經元傳播到嗅球(olfactory bulb)一個位於前腦底部、將信號傳遞給其他大腦區域進行額外處理的結構。
One of these areas is the piriform cortex, a collection of neurons located just behind the olfactory bulb that works to identify the smell. Smell information also goes to the thalamus, a structure that serves as a relay station for all of the sensory information coming into the brain. The thalamus transmits some of this smell information to the orbitofrontal cortex, where it can then be integrated with taste information. What we often attribute to the sense of taste is actually the result of this sensory integration.
其中一個區域是梨狀皮質(piriform cortex),這是一組位於嗅球正後方的神經元,負責識別氣味。氣味信息也會傳送到視丘(thalamus),這是一個作為進入大腦的所有感官信息中繼站的結構。視丘(Thalamus)將部分氣味信息傳輸到眶額皮質(orbitofrontal cortex),在那裡它可以與味覺信息整合。我們經常歸因於味覺的感受,實際上就是這種感官整合的結果。
“The olfactory system is critical when we’re appreciating the foods and beverages we consume,” says Monell Chemical Senses Center scientist Charles Wysocki. This coupling of smell and taste explains why foods seem lackluster with a head cold.
莫內爾化學感官中心科學家查爾斯·維索基(Charles Wysocki)說:「當我們品嚐所消費的食物和飲料時,嗅覺系統至關重要。」嗅覺和味覺的這種結合解釋了為什麼當我們患感冒時,食物會顯得平淡無味。
You’ve probably experienced that a scent can also conjure up emotions and even specific memories, like when a whiff of cologne at a department store reminds you of your favorite uncle who wears the same scent. This happens because the thalamus sends smell information to the hippocampus and amygdala, key brain regions involved in learning and memory.
您可能曾經體驗過氣味也能喚起情緒,甚至是特定的記憶,比如在百貨公司聞到的一股古龍水讓您想起了使用相同香水的您最喜歡的叔叔。發生這種情況是因為丘腦將氣味信息發送到海馬體(hippocampus)和杏仁核(amygdala)——這些是與學習和記憶相關的關鍵大腦區域。
Although scientists used to think that the human nose could identify about 10,000 different smells, Vosshall and her colleagues have recently shown that people can identify far more scents. Starting with 128 different odor molecules, they made random mixtures of 10, 20, and 30 odor molecules, so many that the smell produced was unrecognizable to participants. The researchers then presented people with three vials, two of which contained identical mixtures while the third contained a different concoction, and asked them to pick out the smell that didn’t belong. Predictably, the more overlap there was between two types of mixtures, the harder they were to tell apart. After calculating how many of the mixtures the majority of people could tell apart, the researchers were able to predict how people would fare if presented with every possible mixture that could be created from the 128 different odor molecules. They used this data to estimate that the average person can detect at least one trillion different smells, a far cry from the previous estimate of 10,000. The one trillion is probably an underestimation of the true number of smells we can detect, said Vosshall, because there are far more than 128 different types of odor molecules in the world.
儘管科學家過去認為人類的鼻子可以識別大約 10,000 種不同的氣味,但沃斯霍爾和她的同事最近證明,人類可以識別遠超這個數量的氣味。他們從 128 種不同的氣味分子開始,製作了 10 種、20 種和 30 種氣味分子的隨機混合物,數量之多以至於參與者無法識別所產生的氣味。然後,研究人員向人們展示三個小瓶,其中兩個含有相同的混合物,而第三個含有不同的混合物,並要求他們挑出不屬於的那種氣味。
可以預見的是,兩種混合物之間的重疊越多,就越難區分它們。在計算出大多數人可以區分多少種混合物後,研究人員能夠預測如果呈現給人們可以由 128 種不同氣味分子創造出來的所有可能混合物,人們將會有怎樣的表現。他們利用這些數據估計,一般人至少可以檢測到一萬億(一兆)種不同的氣味,這與之前估計的 10,000 種相去甚遠。
沃斯霍爾說,一萬億這個數字可能低估了我們實際能檢測到的氣味數量,因為世界上擁有的氣味分子遠不止 128 種。
可以預見的是,兩種混合物之間的重疊越多,就越難區分它們。在計算出大多數人可以區分多少種混合物後,研究人員能夠預測如果呈現給人們可以由 128 種不同氣味分子創造出來的所有可能混合物,人們將會有怎樣的表現。他們利用這些數據估計,一般人至少可以檢測到一萬億(一兆)種不同的氣味,這與之前估計的 10,000 種相去甚遠。
沃斯霍爾說,一萬億這個數字可能低估了我們實際能檢測到的氣味數量,因為世界上擁有的氣味分子遠不止 128 種。
No longer should humans be considered poor smellers. In fact, many recent studies have shown that our noses can outperform our eyes and ears, which can discriminate between several million colors and about half a million tones.
事實上,許多最近的研究表明,我們的鼻子可以超越我們的眼睛和耳朵,後者可以區分數百萬種顏色和大約五十萬種音調。
核心要點總結
嗅覺器官:氣味始於鼻腔後部的嗅上皮,其中包含數百萬個感覺神經元。
感應機制 :氣味分子充當鑰匙,與感覺神經元上的受體(蛋白質)這把鎖結合。
受體數量與結合:人類有約 450 種嗅覺受體。一個受體可被多種氣味分子激活,一個氣味分子也可激活多種受體,形成一個神經代碼。
大腦處理路徑:訊號從嗅上皮傳到嗅球,然後傳遞到 1. 梨狀皮質:用於識別氣味。 2. 視丘(Thalamus)(中繼站):傳輸到眶額皮質,與味覺整合。
情緒與記憶:視丘(Thalamus)也會將訊號傳送到海馬體(記憶)和杏仁核(情緒),解釋氣味與記憶和情感的強烈連結。
氣味分辨能力:科學家最新估計,人類平均可以檢測出至少一萬億 (一兆) 種不同的氣味,遠高於過去的 10,000 種估計。
核心要點總結
嗅覺器官:氣味始於鼻腔後部的嗅上皮,其中包含數百萬個感覺神經元。
感應機制 :氣味分子充當鑰匙,與感覺神經元上的受體(蛋白質)這把鎖結合。
受體數量與結合:人類有約 450 種嗅覺受體。一個受體可被多種氣味分子激活,一個氣味分子也可激活多種受體,形成一個神經代碼。
大腦處理路徑:訊號從嗅上皮傳到嗅球,然後傳遞到 1. 梨狀皮質:用於識別氣味。 2. 視丘(Thalamus)(中繼站):傳輸到眶額皮質,與味覺整合。
情緒與記憶:視丘(Thalamus)也會將訊號傳送到海馬體(記憶)和杏仁核(情緒),解釋氣味與記憶和情感的強烈連結。
氣味分辨能力:科學家最新估計,人類平均可以檢測出至少一萬億 (一兆) 種不同的氣味,遠高於過去的 10,000 種估計。
相對能力:鼻子在分辨氣味的能力上,可以超越眼睛(數百萬種顏色)和耳朵(約五十萬種音調)。
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