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1.
涡虫无性繁殖次数,周期和温度的实验观察   总被引:6,自引:0,他引:6  
室温下涡虫的无性繁殖4月开始,9月趋于停止,生殖高峰期在6月。1年中涡虫可进行7-8次无性生殖,生殖周期为7-20天,4-5月生殖的幼涡虫当年可进行2-4次生殖,生殖周期18-27天,涡虫无性生殖的适宜温度为18-29℃,最适宜生殖温度24~26℃。  相似文献   

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珠颈斑鸠繁殖生态初步观察   总被引:3,自引:3,他引:3  
珠颈斑鸠在扬州市每年繁殖1-2次,每年在4月配对,雄鸟常发出3声,4声及两声求偶鸣叫,还要进行“婚飞”,雄鸟问雌鸟点头或鞠躬、对飞等行为。雌雄鸟营巢于树干的中层,巢的结构简单。满窠产卵两株。孵卵期17-18天。育雏期19-20天。  相似文献   

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三道眉草鹀(EmberizoCioides)在山东省的泰山和徂徕山,每年繁殖一次,繁殖期在6-7月。每窝产卵多为4枚,孵卵期11天,育雏期13天。据1992年1月对18只鸟体的检析,冬季年龄的组成,其成体和幼体为1:1,而雌体的只数多于雄体。  相似文献   

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四爪陆龟的活动节律   总被引:4,自引:1,他引:4  
本文报道了四爪陆龟(Testudo hosfieldi)自出蛰到入蛰过程的活动节律。四爪陆龟于3月末4月初出蛰,出蛰后的早期活动为单峰型,高峰期在13-15点钟时,活动性不强。之后直至入蛰的活动为双峰型,两峰约在上午10-12点钟和下午18-20点钟。日活动可分为转身期、日光浴期、前活动期、避暑期、后活动期和夜息期。6月末7月初开始入蛰,有的可持续到8月。自4月到8月,平均昼夜活动时间为6.7小时  相似文献   

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四川清风藤根皮中三萜成分的研究   总被引:7,自引:0,他引:7  
从四川清风藤(Sabia schum anniana Diels)的根皮分离到5 个三萜化合物,根据理化常数、波谱分析及配合衍生物制备,分别鉴定为:3-氧,Δ11,13(18)-齐墩果二烯(1)、3,11-二氧,Δ12-齐墩果烯(2)、3β-羟基,Δ11,13(18)-齐墩果二烯(3)、3-氧,11α-羟基,Δ12-齐墩果烯(4)和3β,11α-二羟基,Δ12-齐墩果烯(5)。其中,4为新化合物  相似文献   

6.
笼养白腹锦鸡觅食活动的观察   总被引:8,自引:2,他引:8  
笼养条件下白腹锦鸡(Chrysolophus amherstiae)的日觅食活动呈现早(7:00-8:00)和晚(18:00-19:00)两个明显高峰期,不同季节和天气其觅食节律有一定的差异;在一年中9月翌年4月的觅食频次较高,这可能与鸟类补充繁殖期能量消耗、积累能量御寒和保证生殖腺发育有关;逐步回归分析结果表明:影响雄鸟觅食活动的主要因素为求偶、理羽和游走;影响雄鸟觅食的主要因素是游走、理羽和静  相似文献   

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纵纹腹小Xiao繁殖生态   总被引:1,自引:1,他引:1  
1982-1991年的3月到9月,在山西庞泉沟自然保护区对纵纹腹小Xiao的繁殖生态进行了研究。繁殖前(3月)种群密度为0.100(只/km),繁殖后(8月)为0.118。4月初产卵,窝卵数3-5枚,孵化期22天左右,巢内,巢外育雏抚幼35-40天,食物以鼠类为主。  相似文献   

8.
纵纹腹小鸮繁殖生态   总被引:2,自引:1,他引:1  
1982-1991年的3月到9月,在山西庞泉沟自然保护区对纵纹腹小的繁殖生态进行了研究。繁殖前(3月)种群密度为0.100(只/km),繁殖后(8月)为0.118。4月初产卵,窝卵数3-5枚,孵化期22天左右,巢内、巢外育雏抚幼35-40天,食物以鼠类为主。  相似文献   

9.
红隼的生态和繁殖生物学观察   总被引:4,自引:2,他引:4  
1989-1991年的4-8月,在山西庞泉沟自然保护区,对红隼生态和繁殖生物学进行了观察。已知该鸟的栖息地有三种:营巢地、觅食地和短暂停息地,利用率分别为39.42%、40.37%和20.19%。该鸟的种群密度在繁殖前4月为2.06,繁殖后的8月为2.89,繁殖后比繁殖前的种群密度增加40.29%。该鸟营巢于悬崖峭壁的洞穴或石缝;产卵多在5月,产卵与孵卵同步;窝产卵3-6枚,孵化期29-30天。其食物组成为小型啮齿动物、小型鸟类和昆虫,分别占64.26%、31.50%和4.26%。  相似文献   

10.
家蚕滞育生物钟蛋白质Ease A4的纯化及其分子结构分析   总被引:2,自引:0,他引:2  
EaseA4是家蚕卵的一种滞育生物钟蛋白质.产下后2d的家蚕C108品种滞育性卵,经过丙酮脱脂、85℃热处理、硫酸铵沉淀和SephadexG-25凝胶过滤层析初步分离,进一步经过Sep-PakC18脱盐浓缩,HPLC(柱为YMC-PackProtein-RP)分离,通过SDS-PAGE和MALDIMS方法鉴定,纯化得到EaseA4蛋白质.从10g蚕卵最终得到了11.8μgEaseA4.EaseA4由从His到Tyr的155个氨基酸残基构成,蛋白质部分的分子量为16601.其22位氨基酸残基Asn处有一个Asn-X-Thr糖基化场所,并有糖基结合在该部位,糖基的分子量约为760.EaseA4的61位和150位的两个Cys氨基酸残基之间存在二硫键.糖基和二硫键的存在不仅有利于酶蛋白的分离,还可能与酶活性有关  相似文献   

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In experiments on Black Sea skates (Raja clavata), the potential of the receptor epithelium of the ampullae of Lorenzini and spike activity of single nerve fibers connected to them were investigated during electrical and temperature stimulation. Usually the potential within the canal was between 0 and –2 mV, and the input resistance of the ampulla 250–400 k. Heating of the region of the receptor epithelium was accompanied by a negative wave of potential, an increase in input resistance, and inhibition of spike activity. With worsening of the animal's condition the transepithelial potential became positive (up to +10 mV) but the input resistance of the ampulla during stimulation with a positive current was nonlinear in some cases: a regenerative spike of positive polarity appeared in the channel. During heating, the spike response was sometimes reversed in sign. It is suggested that fluctuations of the transepithelial potential and spike responses to temperature stimulation reflect changes in the potential difference on the basal membrane of the receptor cells, which is described by a relationship of the Nernst's or Goldman's equation type.I. P. Pavlov Institute of Physiology, Academy of Sciences of the USSR, Leningrad. I. M. Sechenov, Institute of Evolutionary Physiology and Biochemistry, Academy of Sciences of the USSR, Leningrad. Pacific Institute of Oceanology, Far Eastern Scientific Center, Academy of Sciences of the USSR, Vladivostok. Translated from Neirofiziologiya, Vol. 12, No. 1, pp. 67–74, January–February, 1980.  相似文献   

16.
Evolution of living organisms is closely connected with evolution of structure of the system of regulations and its mechanisms. The functional ground of regulations is chemical signalization. As early as in unicellular organisms there is a set of signal mechanisms providing their life activity and orientation in space and time. Subsequent evolution of ways of chemical signalization followed the way of development of delivery pathways of chemical signal and development of mechanisms of its regulation. The mechanism of chemical regulation of the signal interaction is discussed by the example of the specialized system of transduction of signal from neuron to neuron, of effect of hormone on the epithelial cell and modulation of this effect. These mechanisms are considered as the most important ways of the fine and precise adaptation of chemical signalization underlying functioning of physiological systems and organs of the living organism  相似文献   

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