【单选题】
杂交优势往往在第几代杂交种子中表现最明显。___
A. 1
B. 2
C. 3
D. 4
查看试卷,进入试卷练习
微信扫一扫,开始刷题
答案
A
解析
暂无解析
相关试题
【单选题】
以下不属于人体增强技术类型的是___
A. 短暂性增强
B. 持续性增强
C. 结构性增强
D. 内在增强
【单选题】
大陆漂移学说是由谁提出的___
A. 勒比雄
B. 魏格纳
C. 赫斯
D. 李四光
【单选题】
(1)Whieh of the following descriptions about the characteristics of physiology is wrong?___
A. It is the study of how living organisms work.
B. It illustrates the discipline of the development and the evolution of disease and the essence of disease.
C. It is to study the living phenomena and the function activities of living organs.
D. It is to explain how they are regulated and integrated.
【单选题】
(2) Which of the following are specialized in producing force and movement?___
A. muscle cells
B. connective tissues
C. nerve cells
D. epithelial cells
【单选题】
(3)The fluid environment surrounding each cell is called the___
A. intracellular fluid
B. intracellular fluid
C. internal environment
D. external environment
【单选题】
(4) Which of the following is not the fundamental characteristic of living organisms?___
A. metabolism
B. adaption
C. reproduction
D. passive diffusion
【单选题】
(5)Whicl of the following is a physiological process with negative feedback?___
A. blood coagulation
B. process of passing urine
C. sino-aortic baroreceptor reflex
D. process of parturition
【单选题】
(6)Which of the following is not the characteristic of regulation by hormone?___
A. diffusenin nature
B. longer in duration
C. accurate in action
D. action in overcorrection
【单选题】
7)Which of the following is not the characteristic of cells?___
A. They are bound by the plasma membrane
B. They have the ability to break down large molecules to smaller ones to Liberate energy for their activities
C. They possess a nucleus which contains genetic information in the form of deoxyribonucleicacid(DNA).
D. Living cells can not transform materials.
【单选题】
8)The breakdown of large molecules to smaller ones is called___
A. respiration
B. anabolism
C. catabolism
D. absorption
【单选题】
9) Which of the following descriptions about the characteristics of nervous regulation is wrong?___
A. It responds fast
B. It acts exactly
C. It responds slowly.D.
D. uration is short
【单选题】
10)Which of the following descriptions about the control of body function is wrong?___
A. Homeostasis is kept by feedback control.
B. Negative feedback minimizes the changes, leading to stability.
C. Positive feedback is not useful.
D. Feed-forward makes human body foresee and adapt itself to the environment promptly.
【单选题】
(1)Which of the following parts of knowledge of drugs should be included in pharmacology?___
A. The effects of drugs on man
B. The correlation of biological activity with chemical structure
C. The history, source, physical and chemical properties, compounding, biochemical and physiologicaleffects, mechanisms of action, absorption, distrilbution, biotransformation and excretion.
D. The prevention, recognition, and treatment of drug poisonings
【单选题】
(2)Which of the following is what a clinician is primarily interested in according to the text?___
A. Drugs which can be reasonably limited to those aspects that provide the basis for their rational clinical use
B. Chemical agents that are not used in therapy but are commonly responsible for household and industrial poisoning as well as environmental pollution
C. Drugs which are useful in the prevention,diagnosis and treatment of human disease,or in the prevention of pregnancy.
D. rugs which are useful in the prevention, diagnosis and treatment of human disease, or in the prevention of pregnancy.
【单选题】
(3)Why was the physician not interested in pharmacognosy?___
A. He didn't have to select the proper plants for his prescription
B. He had a broad botanical knowledge
C. Fewer drugs were obtained from natural sources
D. Natural drugs had little difference with synthetic ones
【单选题】
(4)Which of the following is the best way of studying pharmacology for medical students and practitioners?___
A. to have a broad botanical knowledge
B. to select a plant and its preparation
C. to have the ability to purify natural plants
D. to have curiosity that stimulates them to learn about sources of drugs
【单选题】
(5)What are the tasks related to medicines almost complete!y delegated to the pharmacists now?___
A. the physical and chemical properties of medicines
B. the preparing, compounding, and dispensing of medicines
C. dosage forms of medicines available
D. the therapeutic and other uses of medicines
【单选题】
(6) What is a main unique aspect of pharmacodynamics?___
A. Pharmacodynamics is an experimental medical science
B. Pharmacodynamics is focused on the characteristics of drugs
C. Pharmacodynamics borrows freely from both the subject matter and the experimenta techniques of physiology, biochemistry, microbiology, genetics and pathology
D. Pharmacodynamics correlates the entire field of preclinical medicine
【单选题】
7) What time of history does pharmacodynamics date back to?___
A. the second half of the seventeenth century
B. the second half of the eighteenth century
C. the second half of the nineteenth century
D. the second half of the twentieth century
【单选题】
8)What does the research on pharmacodynamics focus on?___
A. study of clinical effect of drugs
B. study of the process of drugs in the body
C. study of the effect and the mechanism of drugs on the body
D. study of the correlation of the actions and effects of drugs with their chemical structure
【单选题】
(9)Which of the following is true when drugs are selected?___
A. It has to be based in part on legal reasons.
B. It has to be based in part on ethical reasons.
C. It has to be based in part on the pharmacological evaluation in man
D. It has to be based in part on the pharmacological evaluation in animals
【单选题】
(10)Why are chemotherapeutic agents useful in therapy?___
A. They stimulate or depress biochemical or physiological function in man in a sufficiently reproducible manner to provide relief of symptoms or, ideally, to alter favorably the course of disease
B. They can produce desired effects with only tolerable undesired effects
C. They have only minimal effects on man but can destroy or eliminate parasites
D. The selectivity of their effects is one of their most important characteristics
【单选题】
1)H. Mario Geysen initially used parallel synthesis as a quick way to identify which small_____ of any given large protein bound to an antibody.___
A. division
B. pieces
C. part
D. fragment
【单选题】
2)Chemists often start a combinatorial synthesis by attaching the first set of building blocks_____ to microscopic beads made of polystyrene.___
A. solid
B. inert
C. soft
D. active
【单选题】
3)The chemical reactions required to link compounds to the beads and later to detach them____ to the synthesis proces.___
A. induce complications
B. make easy
C. introduce complications
D. introduce easy
【单选题】
4)In a parallel synthesis, all the products are_____ separately in their own reaction vessels.___
A. combined
B. assembled
C. joined
D. assorted
【单选题】
(5)In many laboratories today, robots assist with the routine work of parallel synthesis, such as small___ amounts of reactive molecules into the appropriate wells.___
A. sending
B. transporting
C. delivering
D. giving
【单选题】
(6)Scientists can pull out from the mixture the beads that bear biologically active molecules and then,using sensitive detection techniques,___ the molecular makeup of the compound attached.___
A. determine
B. make sure
C. find
D. search
【单选题】
(7)Most pharmaceutical companies today continue to___ parallel synthesis. Which of the following is not appropriate to be filled in the blank?___
A. count in
B. count on
C. depend on
D. rely on
【单选题】
(8)Once they identify a promising substance, they___ make many one-at-a-time modifications to the structure.___
A. laboriously
B. hardly
C. easy
D. effectively
【单选题】
(9)Often these procedures yield a compound having acceptable___ and safety.___
A. strength
B. effect
C. potency
D. effort
【单选题】
10)In many laboratories today, robots___ the routine work of parallel synthesis.___
A. help
B. assist with
C. assist in
D. assist to
【单选题】
(1)Pharmaceutics is an interdisciplinary subject involving___
A. formulation, manufacturing, physical pharmacy, and biopharmaceutics
B. manufacturing
C. physical pharmacy
D. biopharmaceutics
【单选题】
(2)Formulation is about the design, development and evaluation of dosage forms,___
A. discovery of novel drugs
B. analytical methods
C. drug delivery systems and manufacturing process
D. dosing regimen
【单选题】
(3)Biopharmaceutics mainly studies the in vivo process of drugs and metabolites in humans, animals and tissue culture, which specifically involves___
A. absorption and distribution
B. absorption, distribution, metabolism, and excretion
C. metabolism and excretion
D. absorption and excretion
【单选题】
(4)Regarding the definition of bioavailability(BA), BA is related to___
A. total plasma drug concentration only
B. unbound drug concentration in the plasma
C. unbound drug concentration at the target site
D. total plasma drug concentration, and the administered drug dose
【单选题】
(5)Plasma drug concentration is affected by following factors such as___
A. rate of absorption
B. rate and extent of distribution
C. rate ofeli Imination
D. all ofabove
【单选题】
6)Which of the following routes of administration will involve the absorption of drugs?___
A. i.v.injection
B. i.v.infusion
C. Subcutaneous injection, transdermal and oral
D. None of above
【单选题】
(7)Which of the following factors may influence the time course of a drug in the plasma and hence at its site of action?___
A. Food
B. Disease state
C. Route of administration
D. All of above
【单选题】
(8)Please identify the potential biological barriers for an orally administered tablet to be absorbed into the systemic circulation___
A. Sk d dermis
B. Gastrointestinal epithelium
C. Oral mucosal membrane
D. All of above
推荐试题
【判断题】
突然停电将产生大量废品、大量减产,在经济上造成较大损失的用电负荷,为“二级负荷”。
A. 对
B. 错
【判断题】
对于电气控制电路的分析和熟悉,仅仅是在处理故障时。
A. 对
B. 错
【判断题】
对于重大故障,应协同设备的操作者共同写出事故报告单,从中要分析设备故障的原因与性质,提出防范措施,经上级领导批准后再进行故障处理。
A. 对
B. 错
【判断题】
接线脱落或电刷接触不良是造成励磁机不发电的主要原因。
A. 对
B. 错
【判断题】
在 XN2010 型龙门铣床电气控制系统中,其励磁绕组回路中串人电流继电器 FAI , 其作用是为了防止进给电动机失去励磁后造成“飞车”。
A. 对
B. 错
【判断题】
变频器的外部接口电路由多功能输入端子和输出接点、多功能模拟输入/输出信号接点、数字信号输人/输出接点、通信接口四部分组成。
A. 对
B. 错
【判断题】
在生产信息自动推测与处理系统中,上位机要完成工作主要有:加工质量信息的收集和存储,管理文件的形成,下级计算机动作的监视;控制质量的监视等。
A. 对
B. 错
【判断题】
用 NOP 指令取代已写人的指令,对原梯形图的构成没有影响。
A. 对
B. 错
【判断题】
串级调速可以将串人附加电动势而增加的转差功率回馈到电网或者电动机上,因此它属于转差功率回馈型调速方法。
A. 对
B. 错
【判断题】
空心杯形转子异步测速发电机的输出特性具有较高的精度,其转子转动惯量较小,可满足快速性要求。
A. 对
B. 错
【判断题】
为了获得更大的输出电流,可以将多个三端集成稳压器直接并联使用。
A. 对
B. 错
【判断题】
译码器、计数器、全加器和寄存器都是组合逻辑电路。
A. 对
B. 错
【判断题】
实际的运放在开环时,其输出很难调整到零电位,只有在闭环时才能调至零电位。
A. 对
B. 错
【判断题】
施密特触发器能把缓慢变化的模拟电压转换成阶段变化的数字信号。
A. 对
B. 错
【判断题】
额定电流为 100A 的双向晶闸管与额定电流为 50A 的两只反并联的普通晶闸管,两者的电流容量是相同的。
A. 对
B. 错
【判断题】
选择步进电动机时,通常应考虑的指标有:相数、步距角、精度(步距角误差)、起动频率、连续运行频率、最大静转矩和起动转矩等。
A. 对
B. 错
【判断题】
安装前熟悉电气原理图和 PLC 及有关资料,检查电动机、元器件,准备好仪器、仪表、工具和安装材料,并根据电气原理图安装电气管路。
A. 对
B. 错
【判断题】
交磁电机扩大机是一种具有很高放大倍数、较小惯性、高性能、特殊构造的直流发电机。
A. 对
B. 错
【判断题】
阳极不发射电子只吸收来自阴极的电子,管内抽成真空。
A. 对
B. 错
【判断题】
与整流装置并联的其他负载切断时,或整流装置直流侧快速开关跳闸时,电流上升率变化极大,因而整流变压器产生感应电动势并造成过电压。这种过电压是尖峰电压,常用阻容吸收电路加以保护。
A. 对
B. 错
【判断题】
晶闸管触发电路的触发信号可以是交流、直流信号,也可以是脉冲信号。
A. 对
B. 错
【判断题】
整流状态时整流器将交流电能变成直流电能供给电动机。
A. 对
B. 错
【判断题】
来自三块 KC04 触发器 13 号端子的触发脉冲信号,分别送人 KC42 的 2、4、12 端。V1、v2、V3 构成与非门电路。只要任何一个触发器有输出,S点就是低电平,V4 截止,使 V5、v6、v8组成的环形振荡器停振。
A. 对
B. 错
【判断题】
典型工业控制系统是由一次设备部分和工业控制系统组成。一次设备通常由被控对象、变送器和执行机构组成。工业控制系统包括硬件系统和软件系统。
A. 对
B. 错
【判断题】
创新既不能墨守成规,也不能标新立异。
A. 对
B. 错
【判断题】
职业道德是指从事一定职业的人们,在长期职业活动中形成的操作技能。
A. 对
B. 错
【判断题】
JK 触发电路中,当 J = 1、 K = 1、 Qn 二 1 时,触发器的状态为置 1 。
A. 对
B. 错
【判断题】
CW7805 的 U。=5v、它的最大输出电流为 1.5v 。
A. 对
B. 错
【判断题】
在 R ’=Ri的状态下,无论从功率或效率的角度来看,都比较理想,故这种状态称为振荡器的最佳状态。
A. 对
B. 错
【判断题】
为防止中频电流在 Cd 产生较高的中频电压,影响逆变器的运行, Cd 的容量要足够大,可认为整流器输出为一恒流源。
A. 对
B. 错
【判断题】
查阅设备档案,包括设备安装验收记录、故障修理记录,全面了解电气系统的技术状况。
A. 对
B. 错
【判断题】
逻辑代数的基本公式和常用公式中同一律 A+0=A, Axl=A 。
A. 对
B. 错
【判断题】
根据真空晶体管的特性曲线可以看出,改变栅极电流就可使阳极电流发生变化。
A. 对
B. 错
【判断题】
直线运动各轴的反向误差属于数控机床的定位精度检验。
A. 对
B. 错
【判断题】
由于各种原因所引起的故障报警时,报警指示灯亮。可进一步通过编程器查看报警信息。
A. 对
B. 错
【判断题】
根据梯形图分析和判断故障是诊断所控制设备故障的基本方法。
A. 对
B. 错
【判断题】
两电压叠加后产生脉冲前沿幅度很低,陡度很小的触发脉冲,从而大大提高了对晶闸管触发的可靠性。
A. 对
B. 错
【判断题】
带有辅助晶闸管换流电路的特点是,主晶闸管的关断是由 LC 串联谐振电路中电流反向来实现。
A. 对
B. 错
【判断题】
串联二极管式逆变器,在变频调速系统中应用广泛, VD1~VD6 为隔离二极管,其作用是使换流回路与负载隔离,防止电容器的充电电压经负载放掉。
A. 对
B. 错
【判断题】
为了实现频率的自动跟踪,逆变触发电路采取自激工作方法,自激信号来自负载端。
A. 对
B. 错