生物学
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相似问题和答案
第1题：
The sound of "th" in "thin" is__________.
A.voiceless, dental, and fricative
B.voiced, dental, and fricative
C.voiceless, dental, and affricative
D.voiced, dental, and affricative
B.voiced, dental, and fricative
C.voiceless, dental, and affricative
D.voiced, dental, and affricative
答案：A
解析：
考查辅音的发音。本题属于语音知识，也属于语言学中语音学的知识。th字母组合在单词thin中发／θ／音，发此音时，声带是不振动的，即不带声的(voiceless)；另外，发／θ／音时舌头要顶住牙齿，所以叫齿音(dental)；按照发音方式，它是空气通过与牙齿摩擦发出的声音，属于摩擦音(fricative)。故选A。
第2题：
牙石 dental calculus
正确答案: 沉积在牙面或修复体上的已钙化的或正在钙化的菌斑及沉积物，由唾液或龈沟液中的矿物盐逐渐沉积而成。
第3题：
plaque forming unit，PF[J
正确答案：plaque forming unitPFU：The plaque assay is the most widly used assay for infectious virus．Monolayers ofhost cells are inoculated with suitable dilutions of virusand affter adsorption aye overlaid with medium containingagar or carboxyme thyicellulose to prevent virus spreadingthroughout the culture．Affter several daysthe cell s inital—ly infected have produced virus that spreads only to sur—rounding cellsproducing a small area of infection or plaque．Under controlled conditionsa single plaque can arise form a single infectious virus particletermed aplaque—forming unit．
plaque forming unit，PFU：The plaque assay is the most widly used assay for infectious virus．Monolayers ofhost cells are inoculated with suitable dilutions of virusand affter adsorption aye overlaid with medium containingagar or carboxyme thyicellulose to prevent virus spreadingthroughout the culture．Affter several days，the cell s inital—ly infected have produced virus that spreads only to sur—rounding cells，producing a small area of infection or plaque．Under controlled conditions，a single plaque can arise form. a single infectious virus particle，termed aplaque—forming unit．
plaque forming unit，PFU：The plaque assay is the most widly used assay for infectious virus．Monolayers ofhost cells are inoculated with suitable dilutions of virusand affter adsorption aye overlaid with medium containingagar or carboxyme thyicellulose to prevent virus spreadingthroughout the culture．Affter several days，the cell s inital—ly infected have produced virus that spreads only to sur—rounding cells，producing a small area of infection or plaque．Under controlled conditions，a single plaque can arise form. a single infectious virus particle，termed aplaque—forming unit．
第4题：
非附着性龈下菌斑（unattached subgingival plaque）
正确答案:不附着于牙面或牙根面，却与结合上皮和龈沟上皮直接接触的菌斑。
第5题：
牙菌斑（plaque）
正确答案:堆积在牙表面或其他硬的口腔结构上，不能被中度水喷冲去的细菌团块。
第6题：
Which of the following correctly describes the English phoneme/θ/
A.A voiceless dental fricative.
B.A voiceless alveolar fricative.
C.A voiceless dental plosive.
D.A voiceless alveolar plosive.
B.A voiceless alveolar fricative.
C.A voiceless dental plosive.
D.A voiceless alveolar plosive.
答案：A
解析：
考查音素的分类。voiceless“不带声(清音的)”，dental“齿音”，alveolar“齿龈音”，fi'icative“摩擦音”，plosive“爆破音”，／θ／属于清音、齿音、摩擦音，故选A。
第7题：
简述dental plaque biofilm的临床意义。
正确答案: 牙菌斑生物膜：细菌黏附于获得性膜形成牙菌斑
(1)龈上菌斑：窝沟裂隙邻接面龋
龈下菌斑：根面龋、根面吸收、牙周炎骨吸收
(2)牙菌斑生物膜是一个生态群体，细菌附着紧密，难以消除。用药物辅助控制菌斑时，在使用药物前或使用药物中，需要先去除菌斑或搅乱生物膜，以达到较好效果。
(3)牙菌斑生物膜的形成，与牙面光洁度、饮食摄入类型等相关。为控制菌斑形成，需要保持牙面光洁度。摄入饮食少粘软。
第8题：
The sound of "ch" in "teacher" is（ ）.
A.voiceless, post-alveolar, and affricative
B.voiceless, dental, and fricative
C.voiced, dental, and fricative
D.voiced, post-alveolar, and plosive
B.voiceless, dental, and fricative
C.voiced, dental, and fricative
D.voiced, post-alveolar, and plosive
答案：A
解析：
本题考查字母组合的发音。字母组合ch在单词teacher中发/t/的音。辅音有多种分类方式。从声带振动上来看，/t/为清辅音(voiceless)；从发音部位上来看，/t/为齿龈后音(post-alveolar)；从发音方式上来看，/t/为塞擦音（affricative）。
第9题：
龋病（dental caries）
正确答案:牙在外界因素的影响下，牙釉质、牙本质或牙骨质发生的一种进行性破坏的疾病，其本质是一种细菌感染性疾病。
第10题：
纤维斑块(fibrous plaque)
正确答案: 指动脉粥样硬化的中晚期，在病灶周围特别是其表面纤维结缔组织增生，形成突出于内膜表面的纤维斑块，脂质被埋于深层。