下列关于低温诱导染色体加倍实验的叙述，正确的是

【名词&注释】

减数分裂(meiosis)、向日葵(sunflower)、细胞膜通透性(membrane permeability)、组织细胞(histocyte)、纺锤体、混合液(mixture)、细胞有丝分裂(cell mitosis)、母细胞(mother cell)、大多数(most)、每个人(everyone)

[单选题]下列关于低温诱导染色体加倍实验的叙述，正确的是

A. 原理：低温抑制染色体着丝点分裂，使子染色体不能分别移向两极
B. 解离：盐酸酒精混合液和卡诺氏液都可以使洋葱根尖解离
C. 染色：改良苯酚品红溶液和醋酸洋红溶液都可以使染色体着色
D. 观察：显徽镜下可以看到大多数^(most)细胞的染色体数目发生改变

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学习资料：

[单选题]______________________________________________________________________Specialized dictionaries provide in-depth information about a certain field. For example, there are dictionaries for the specialized vocabularies of law, computer technology, and medicine. In addition, there are dictionaries of synonyms, clichés, slang, and even regional expressions, such as the Dictionary of American Regional English (DARE). There are also dictionaries of foreign languages, famous people’s names, literary characters’ names and place names.

A. Varieties of college dictionaries
B. Accessing dictionaries electronically
C. Elements under a word item
D. Complete editions of dictionaries
E. Using dictionaries for particular fields
F. F. Features of college dictionaries

[单选题]CPeople from East Asia tend to have more difficulty than those from Europe in distinguishing facial expressions--and a new report published online in Current Biology explains why.

A. Rachael Jack, University of Glasgow researcher, said that rather than scanning evenly
B. (均匀的) across a face as Westerners do, Easterners fix their attention on the eyes.
C. "We show that Easterners and Westerners look at different face features to read facial expressions," Jack said. "Westerners look at the eyes and the mouth in equal measure, whereas Easterners favor the eyes and neglect (忽略) the mouth."
D. According to Jack and her colleagues, the discovery shows that human communication of emotion is more complex than previously believed. As a result, facial expressions that had been considered universally recognizable cannot be used to reliably convey emotion in cross-cultural situations.
E. The researchers studied cultural differences in the recognition of facial expressions by recording the eye movements of 13 Western Caucasian and 13 East Asian people while they observed pictures of. expressive faces and put them into categories: happy, sad, surprised, fearful, disgusted, angry, or neutral. They compared how accurately participants read those facial expressions using their particular eye movement strategies.
F. It turned out that Easterners focused much greater attention on the eyes and made significantly more errors than did Westerners. "The cultural difference in eye movements that they show is probably a reflection of cultural difference in facial expressions," Jack said. "Our data suggest that whereas Westerners use the whole face to convey emotion, Easterners use the eyes more and mouth less."
G. In short, the data show that facial expressions are not universal signals of human emotion. From here on, examining how cultural factors have diversified these basic social skills will help our understanding of human emotion. Otherwise, when it comes to communicating emotions across cultures, Easterners and Westerners will find themselves lost in translation.
H. 66. The discovery shows that Westerners __
I. pay equal attention to the eyes and the mouth
J. consider facial expressions universally reliable
K. observe the eyes and the mouth in different ways
L. have more difficulty in recognizing facial expressions

[单选题]

A. after
B. until
C. when
D. since

[单选题]向日葵的雄蕊是( )。

A. 单体雄蕊
B. 二体雄蕊
C. 聚药雄蕊
D. 多体雄蕊

[单选题]花粉母细胞^{(mother cell)}经过减数分裂产生4个大孢子。( )

A. 正确
B. 错误

[单选题]松、杨分枝方式属于( )。

A. 单轴分枝
B. 合轴分枝
C. 假二叉分枝
D. 二叉分枝

[单选题]佛焰花序属于肉穗花序。( )

A. 正确
B. 错误

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