北京颐和园鸟巢和卵的初步调查

鸟类的营巢和产卵是它们在繁殖过程中的重要阶段。鸟巢的结构、形状,营巢(包括窝)的材料、处所、期间,卵的色泽.大小,形状,产卵的日期以及一窝卵的数目等,都是十分复杂的。不仅在不同种的鸟差异很大 即使是同种鸟也随着它们棲住地区的环境条件的不同,而有些变化。研究鸟巢和卵的目的下仅在于阐明鸟类生物学中的某些专门性问题,也给农林益鸟的保护和招引以及害鸟的防除,提供了科学资料。     

北海道惠庭市招致设立生物技术专门学校

北海道惠庭市已招致设立生物技术专门学校作为惠庭High Complex City(高度综合性城市)构想的研究核心(research core)的一部分。1987年2月26日进行正式签字。惠庭高度综合性城市构想是由惠庭市、北海道以及通商产业省等共同努力实施的地区性开发计划,其中心是研究核心。     

海星卵和海胆卵的人工受精及其早期发育的观察方法

我国沿海常见的棘皮动物如海星和海胆的卵,都是动物早期发育和试验胚胎学极好的实验材料。棘皮动物全都是雌雄异体的,但在外表上雌雄却不易辨别。它们各有五对生殖腺。它们的卵含有少量的卵黄,属     

卵菌类减数分裂与染色体倍性问题

卵菌类减数分裂与染色体倍性问题１００多年来对卵菌的研究不断深入,有关卵菌的一些生物学问题曾引起了激烈的讨论,如早期将它们归于藻状菌纲中的双鞭毛菌组（Ｂｉｆｌａｇｅｌｌａｔａｅ）,现在一般将它们归于鞭毛菌亚门中的卵菌纲（Ｏｏｍｙｃｅｔｅｓ）。它们的无性...     

荔蝽卵平腹小蜂越冬环境初步调查

荔蝽卵平腹小蜂Anastatussp．是一种卵寄生蜂,主要寄生于荔枝蝽TessaratomapapillosaDrary的卵内,对荔枝蝽的为害有一定的控制作用。60年代初,蒲蛰龙等[1]对该蜂生物学特性开展了研究,并成功地利用蓖麻蚕卵、柞蚕卵作为替代寄主大量繁殖此蜂,释放于荔枝园防治荔枝蝽,取得了良好效果。从80年代开始,刘志诚等[2]开展人工卵的研究,取得成功,目前已经形成一套成熟的人工繁蜂、放蜂防治荔枝蝽的技术。但在自然界,该蜂难以形成强大的自然种群,越冬后早春的自然种群数量相当低,早春寄生率不高。在释放平腹小蜂的同时,如何保护它们,…     

林蛙卵第一次卵裂时卵黄粒的超微结构变化

用水溶性电镜包埋介质等四种不同的方法研究了黑龙江林蛙卵第一次卵裂时卵黄粒的精细结构的变化。观察到在2-细胞期已经有一部分卵黄粒开始降解,这比文献报道卵黄粒在囊胚晚期才开始降解要早。卵黄粒降解步骤:1.从晶形主体边缘脱落晶分子,晶分子进入非晶形区之后电子染色加深,使深色亚区扩大面积。2.在深色亚区中出现“微泡”结构。3.从深色亚区转变成浅色亚区并在后者中出现直径600埃左右的具膜小泡,它们可能是从深色亚区中的“微泡”演化而来。4.具膜小泡随着卵黄粒界膜的破损而释出。     

猪卵丘细胞对卵母细胞膜电位影响的研究

本文应用细胞内微电极技术,测试分析了猪卵丘细胞对卵母细胞膜电位的影响。结果表明,卵母细胞周围卵丘细胞的数量和形态特点的差异对卵母细胞膜电位有显著影响,Ａ、Ｂ、Ｃ三类卵母细胞的膜电位有极显著差异。Ａ类和部分Ｂ类母细胞的膜电位为负值,Ｃ类和另一部分Ｂ类卵母细胞的膜电位为正值。     

蓖麻蚕卵受精的研究

我们从细胞形态上的研究, 证明:蓖麻蚕卵在成熟期分裂的中期(同一横剖面), 基组数染色体是14;分作两圈, 内层4个, 外层10个。成熟卵停止在第一次中期分裂, 纺锤体与卵膜垂直, 待精子入卵后继续向前分裂, 并发现有染色质消散的现象。第二次成熟期分裂结果获得3个极体和1个雌性原核。正常的卵平均能接受2-3条精子, 它们入卵后起收缩、囊化成雄性原核;其中一个与雌性原核合并为“双组核”。剩余的过数精核分裂缓慢, 终于中心体离纺锤体作异形的分裂。     

关于泥蚶卵成熟的初步探讨

为了解决养蚶业中苗种的不足,目前对泥蚶Arca(Anadara)granosa Linne的繁殖规律,特别是它的发生及幼贝生态的研究,已引起我国水产工作者的重视。但在自然海区里,与泥蚶生殖期相近的双壳类很多,它们早期发育的形态极相似,采集自然产卵发育的幼体,     

关于羊膜卵的进货的假想

羊膜动物是从无羊膜动物进化来的,它们的卵在结构和适应力方面差异极大,特别是胚外膜呈现“全或无”的状态。它们之间存在进化上的缺环。本文从脊椎动物上陆的历史背景入手,结合胚胎学的实验事实和当时的环境条件,分析卵的进化,提出关于原羊膜卵的假想,以补卵的进货缺环。     

新疆维吾尔自治区的蝗虫研究蝗虫的分布(续)

新疆的蝗虫区系与区域分布,上文已作了分析探讨(陈永林,1980),本篇讨论新疆的蝗虫生态地理分布规律。 三、生态地理分布 根据新疆的蝗虫分布与生态地理因素之间的关系,可以认为地形、气候、植被、土壤等因素对蝗虫分布的影响是综合的;其中,植被、小气候以及土壤的类型与分布的关系尤为直接和密切。前者与蝗虫的食性、发育生殖,后二者与蝗虫行为习性,特别是分布、水热条     

甜菜夜蛾卵的超低温冷冻保存(英文)

通过对甜菜夜蛾卵超低温冷冻过程中一系列影响因子的研究 ,建立了甜菜夜蛾卵在液氮中冷冻保存的方法。结果表明 ,利用 1 5%次氯酸钠处理卵壳 6min ,再用异丙醇处理 1 5sec和N 己烷处理 30sec可有效去除甜菜夜蛾卵的外卵壳和蜡质层 ,获得 95%以上的渗透化率和 60 %左右的存活率 ;渗透化卵经 2mol L乙二醇初步抗冻 30min和含 1 0 %BSA的 8 5mol L乙二醇脱水 5min ,约有 55%～ 60 %的卵存活和2 4 %的卵孵化 ;将抗冻处理后的卵投入液氮 ( - 1 96℃ )中 2 4h ,在 37℃下解冻 ,结果有 ( 1 6 3± 7 6) %的卵发育至黑头期 ,( 1 6± 1 1 ) %的卵孵化。     

长毛对虾卵子皮层反应的研究

Morphology of the cortical reaction in the eggs of Penaeus penicillatus was studied with the light microscopy,scanning electron microscopy　and transmission electron microscopy. The cortical reaction is divided into four stages. These stages are unreacted stages, early stages, corona stages and dissipation stage. The cortical rods were released and formed a jelly coating around the surface of the egg. The jelly coating remained until the first cleavage had finished. In the end, the hatching membrane appeared around the egg. It is believed that these cortical reaction are responsible for the prevention of polyspermy by both a chemical and physical block and that also may establish a microenvironment inside a touch chorionic membrane for the developing embryo.     

THE ACTIVATION OF STARFISH EGGS BY ACIDS

The accompanying slip is to replace the correction which appeared in front of Vol. viii, No. 5, June 20, 1926. On page 348, Vol. viii, No. 4, April 20, 1926, in the last line of foot-note 17, for the expression 0.8/22.4 x 295/273 = 0.034 read 0.8 ÷ (22.4 x 295/273) = 0.034.     

CRYOPRESERVATION OF THE BEET ARMYWORM EGGS*

Abstract A protocol for cryopreservation of the eggs of beet armyworm Spodoptera exigua (Lepidoptera: Noctuidae) in liquid nitrogen was established after examining the effects of a number of factors on the survival of the eggs during various stages of cryopreservation. Over 95% of eggs incubated at 271) for 33 h were permeabilized and about 60% of them could hatch using the following permeabilization procedure: dechorionation of eggs in 15% sodium hypochlorite for 6 min followed by immersion in isopronol for 15 sec to remove surface water and then in n‐hexane for 30 sec to dissolve the wax layer. Immersion of the permeabilized eggs in 2 mol/L ethylene glycol for 30 min and then dehydration in 8.5 mol/L ethylene glycol solution containing 10% BSA for 5 min led to 55%? 60% survival and approximately 24% hatching rate. Eggs cryopreserved in liquid nitrogen using the recommended protocol have a survival rate of (16.3 ± 7.6)% and a hatching rate of (1.6 ± 1.1)%.     

某些天蛾的卵与产卵方式

天蛾产卵的方式不同,产卵量与卵的形状互有差异。多年来在观察天蛾科的生活习性中,发现天蛾卵形与产卵方式和天蛾的身体构造、生活习性、亚科系统以及植物寄主均密切相关,这些关系值得注意。 卵量 天蛾科的产卵量一般为200粒左右,但丁香天蛾Psilogramma increta及构月天蛾Parumcolligata的产卵量可达1,000粒以上。 卵形 不同种类的天蛾,卵的形状颇有不同,大致可分为:1.球形——圆如球,以卵底紧贴叶面,与叶面接触处是平面,卵孔在顶部。如小豆长喙天蛾Macroglossum stellatarum卵(图1)。2.扁圆形——圆而略扁,以卵的长轴与叶面并行,卵孔位于顶部偏下方。如雀纹天蛾Theretra japonica卵(图2)。3.椭     

THE ACTIVATION OF STARFISH EGGS BY ACIDS

1. Exposure of unfertilized starfish eggs to dilute solutions of weak acids (fatty acids, benzoic and carbonic acids) in isotonic balanced salt solution causes complete activation with the proper durations of exposure. For each acid the rate of activation (reciprocal of optimum duration) varies with concentration and temperature; at a given temperature and within a considerable range of concentrations (e.g. 0.00075 to 0.004 M for butyric acid), this rate is approximately proportional to concentration. We may thus speak of a molecular rate of action characteristic of each acid. 2. In general the molecular rate of action increases with the dissociation constant and surface activity of the acids. In the fatty acid series (up to caproic), formic acid has the most rapid effect, acting about four times as rapidly as acetic; for the other acids the order is: acetic = propionic ≦ butyric < valeric < caproic. Carbonic acid acts qualitatively like the fatty acids, but its molecular rate of action is only about one-fourteenth that of acetic acid. 3. Hydrochloric and lactic acids are relatively ineffective as activating agents, apparently because of difficulty of penetration. Lactic acid is decidedly the more effective. The action of both acids is only slightly modified by dissolving in pure (isotonic NaCl and CaCl₂) instead of in balanced salt solution. 4. The rate of action of acetic acid, in concentrations of 0.002 M to 0.004 M is increased (by 10 to 20 per cent) by adding Na-acetate (0.002 to 0.016) to the solution. The degree of acceleration is closely proportional to the estimated increase in undissociated acetic acid molecules. Activation thus appears to be an effect of the undissociated acid molecules in the external solution and not of the ions. Acetate anions and H ions acting by themselves, in concentrations much higher than those of the solutions used, have no activating effect. The indications are that the undissociated molecules penetrate rapidly, the ions slowly. Having penetrated, the molecules dissociate inside the egg, yielding the ions of the acid. 5. When the rate of activation is slow, as in 0.001 M acetic acid, the addition of Na-acetate (0,008 M to 0.016 M) has a retarding effect, referable apparently to the gradual penetration of acetate ions to the site of the activation reaction with consequent depression of dissociation. 6. An estimate of the C_H of those solutions (of the different activating acids) which activate the egg at the same rate indicates that their H ion concentrations are approximately equal. On the assumptions that only the undissociated molecules penetrate readily, and that the conditions of dissociation are similar inside and outside the egg, this result indicates (especially when the differences in adsorption of the acids are considered) that the rate of activation is determined by the C_H at the site of the activation reaction within the egg.