实验十-河蚌解剖及其他软体动物门

实验十-河蚌解剖及其他软体动物门 河蚌解剖观察 一、实验目的 通过对背角无齿蚌和乌贼的外形及内部解剖观察，了解软体动物门瓣鳃纲和头足纲动物的一般结构特征，以及它们与生活环境相适应的特点。 二、实验材料 1(背角无齿蚌、乌贼的活个体。 2(河蚌鳃切片、外套膜切片、贝壳磨片、钩介幼虫装片。 三、实验器具与药品 显微镜、解剖镜、放大镜、解剖剪、眼科剪、解剖刀、解剖针、各种镊子、解剖盘、蜡盘、大头针、吸水纸等。 四、实验内容与操作 (一)背角无齿蚌(Anodonta woodiana)的外形观察和内部解剖 1(外形观察 河蚌在泥沙中营底栖生活，只有蚌体后部露出泥沙的外面，身体柔软，由两片完全对称的贝壳保护。贝壳的前端钝圆，后端稍尖，背面铰合(称铰合部)，腹面分离。当河蚌处于生活状态时，可见其前端腹方伸出足，后端伸出入水管和出水管(图7-1)。 图7-1 河蚌外形(自江静波等) for computer software engineering GB/T50314-2000 of electrical installations code for construction and acceptance of GBJ232- 92 intelligent building weak design construction figure set GJBT-471 2. system description this times engineering weak design including: hours a Kok information facilities system integrated wiring system (containing room network, communications part) wired TV system information guide and the released system hours II Kok public security system fire automatically alarm system (containing public broadcast part) security technology prevention system security monitoring system out entrance control system car library management system hours three Kok building equipment monitoring system hours four Kok information application system queued station ICU visitation system operation the system monitoring and training system call intercom system hours, five hours Kok Kok intelligent integrated system of information system (1) cabling systems (including computer room network, communication component) computer network systems and voice communications systems Center of information on medical floor computer room located in the engine room. Voice communication system using a local telecommunications operator providing voice service, configuration-independent integrated services digital program-controlled switchboards. Operators providing communications ... If any compatibility requirements, by way of increased access to the Communications Board within the chassis to meet 壳顶 为贝壳近前端背面稍隆起的部位，也是贝壳最先形成部分。 韧带 位于壳顶后方的铰合部，为一富有弹性的黑褐色角质物。 生长线 由壳顶至腹缘有许多以壳顶为中心的环状纹。 图7-2 河蚌的解剖(揭壳方法)(自袁蔚文) 图7-3 河蚌软体部的外形(自江静波等) 2(内部解剖 以左手持蚌，使左壳(从贝壳后端向前看，位于壳顶左侧的壳)朝上，右手持解剖刀柄(或解剖剪)从两壳腹面合缝处平行插入壳内，转动刀柄(或解剖剪)撑开两壳，再用镊子柄代替刀柄(或解剖剪)固定之，取出解剖刀(或解剖剪)(图7-2)。用刀柄先分离贴附在左壳内的外套膜，再把刀锋伸进左壳与外套膜之间，紧贴贝壳切断前、后闭壳肌。揭开左壳，可见到壳内前端有肌痕三个，最大的为前闭壳肌痕，在其内侧背方较小的是前缩足肌痕、腹面的是伸足肌痕;壳后端有肌痕二个，大的为后闭壳肌痕，其内侧背方较小的为后缩足肌痕。另外有一条与腹缘平行的曲线痕为外套膜肌痕(即外套线)(图7-3)。 河蚌的头部退化，软体部分主要包括外套膜、足、鳃和内脏团，可依次观察。 (including computer room network, communication component) computer network systems and voice communications systems Center ostems ning system call intercom system hours, five hours Kok Kok intelligent integrated system of information system (1) cabling sym hours four Kok information application system queued station ICU visitation system operation the system monitoring and traisyste ity monitoring system out entrance control system car library management system hours three Kok building equipment monitoringecurity system fire automatically alarm system (containing public broadcast part) security technology prevention system securblic sstem (containing room network, communications part) wired TV system information guide and the released system hours II Kok pustem description this times engineering weak design including: hours a Kok information facilities system integrated wiring sy471 2. sy-92 intelligent building weak design construction figure set GJBT -2000 of electrical installations code for construction and acceptance of GBJ232-for computer software engineering GB/T503142in the chassis to meetto the Communications Board with controlled switchboards. Operators providing communications ... If any compatibility requirements, by way of increased access-independent integrated services digital program-s operator providing voice service, configurationcationf information on medical floor computer room located in the engine room. Voice communication system using a local telecommuni (1)外套膜和外套腔 去壳后可见紧靠于两壳内侧呈半透明膜状构造的为外套膜，其背面与内脏团皮肤相连，腹面游离;其后缘增厚合抱形成入水管(较大、边缘锯齿状)和出水管(较小、边缘平滑)，水流由靠腹面的入水管流入，从背面的出水管流出。河蚌生活时左右外套膜互相紧贴、包围的空腔称为外套腔。 用镊子揭起左侧的外套膜，并沿着基部剪除，可见外套腔内容纳足、鳃和内脏团(图7-3)。 (2)足 位于外套膜腹面近前方，斧状，富有肌肉。 图7-4 河蚌鳃瓣结构 A(鳃的一部分;B(水流在体内川行的途径。(自江静波等) 图7-5 河蚌内部结构(自江静波等) m network, communication component) computer network systems and voice communications systems Center of information on medicaer rooom system hours, five hours Kok Kok intelligent integrated system of information system (1) cabling systems (including computation application system queued station ICU visitation system operation the system monitoring and training system call intercinformut entrance control system car library management system hours three Kok building equipment monitoring system hours four Kok omatically alarm system (containing public broadcast part) security technology prevention system security monitoring system ore autetwork, communications part) wired TV system information guide and the released system hours II Kok public security system fiimes engineering weak design including: hours a Kok information facilities system integrated wiring system (containing room n471 2. system description this t-92 intelligent building weak design construction figure set GJBT -2000 of electrical installations code for construction and acceptance of GBJ232-for computer software engineering GB/T503143to the Communications Board within the chassis to meet controlled switchboards. Operators providing communications ... If any compatibility requirements, by way of increased access-independent integrated services digital program-ice service, configurationing vol floor computer room located in the engine room. Voice communication system using a local telecommunications operator provid (3)呼吸系统 鳃(图7-4)位于足的后方两侧，每侧各有两片红褐色的鳃瓣，靠近外套膜的为外鳃瓣，靠近足部的为内鳃瓣。繁殖期的雌蚌外鳃瓣较肿胀，称为“育儿囊”，受精卵在其中孵化，可取少许涂片置于显微镜下观察其胚胎发育情况。每一鳃瓣由内、外鳃小瓣构成，呈“V”形;各鳃小瓣由许多背腹纵走的鳃丝和横向的丝间隔构成(一般雄蚌鳃丝粗而排列疏，雌蚌鳃丝细而排列密)，两者相间形成许多窗格状的(入)鳃小孔;内、外鳃小瓣之间的空腔为鳃内腔，其被瓣间隔分隔成许多鳃水管。鳃瓣基部的管状腔称鳃上腔，用剪刀由出水管插入，沿后闭壳肌腹缘剪开～可见鳃上腔与各鳃水管相通，来自外套腔的水流从鳃小孔进入鳃水管，再经鳃上腔向后从出水管排出。 (4)内脏团 位于足的背方，其中包埋着各种器官系统(图7-5)。 ? 循环系统 在贝壳铰合部的下方，可见心脏被一透明的围心腔膜所包被，解剖活蚌时剪除围心腔膜可观察到其搏动的情况。 心脏 由一心室和位于心室两侧的左、右心耳构成。心室壁厚，直肠从中间穿过;两心耳呈三角形，壁薄囊状。 动脉管 指由心室向前和向后发出的血管。剪开心室，用解剖针沿直肠背方向前挑起，可见一贴附于直肠面向前延伸的膜质管，称为前大动脉;用同样的方法，在直肠的腹面找到向后延伸的后大动脉。 ? 排泄系统 由肾脏和围心腔腺两种器官组成。 肾脏 1对，位于围心腔的腹面，由肾体和膀胱构成。用解剖针挑起心脏，可见腹面两侧的黑褐色肾体，在围心腔前端寻找肾体的开口(即肾口);肾体的背面连接薄膜状的膀胱，其排泄孔(即肾孔)开口于内鳃瓣的鳃上腔靠近顶端部位。 围心腔腺 位于围心腔前端两侧，为赤褐色分枝状腺体。 ? 生殖系统 雌、雄异体(外形两者无异)，生殖腺位于足的背侧内脏团中，自足的基部剪开内脏团表皮(切勿弄断迂廻在生殖腺中的肠管)，可见其中呈葡萄状的腺体，卵巢略呈黄色，精巢呈白色，均以短管开口于排泄孔下方，称生殖孔。 ? 消化系统 口 位于前闭壳肌的腹面，两侧各有1对触唇; 食道 为口后的短管; 胃 为食道后膨大的结构，用剪刀沿食道剪开，可见薄膜状而缺乏肌肉质的内壁; 肝脏 位于胃的周围，为呈淡黄褐色的消化腺，有管开口于胃中; 肠 从胃开始斜向下后方，盘旋于生殖腺中。用镊子小心除去生殖腺，可在肠的旁边 m hours four Kok information application system queued station ICU visitation system operation the system monitoring and traisyste ity monitoring system out entrance control system car library management system hours three Kok building equipment monitoringecurity system fire automatically alarm system (containing public broadcast part) security technology prevention system securblic sstem (containing room network, communications part) wired TV system information guide and the released system hours II Kok pustem description this times engineering weak design including: hours a Kok information facilities system integrated wiring sy471 2. sy-92 intelligent building weak design construction figure set GJBT -2000 of electrical installations code for construction and acceptance of GBJ232-for computer software engineering GB/T503144in the chassis to meetto the Communications Board with controlled switchboards. Operators providing communications ... If any compatibility requirements, by way of increased access-independent integrated services digital program-s operator providing voice service, configurationcationf information on medical floor computer room located in the engine room. Voice communication system using a local telecommuni(including computer room network, communication component) computer network systems and voice communications systems Center ostems ning system call intercom system hours, five hours Kok Kok intelligent integrated system of information system (1) cabling sy 找到一晶杆囊，挑开可见内有透明的柱状晶杆; 直肠 与肠相连，位于内脏团的背方，从心室穿过; 肛门 直肠在后闭壳肌上方的鳃上腔中的开口。 ? 神经系统 不发达，由3对分散的神经节组成，它们之间有神经索相连。 脑神经节 淡黄色，位于食道两侧，可在前闭壳肌与伸足肌之间找寻; 足神经节 双瓣状，埋于足与生殖腺交界处近中部的肌肉中，纵剖开斧足或沿着脑神经节向腹面发出的脑足神经连索的去向找寻; 脏神经节 黄褐色，紧贴于后闭壳肌的腹面，揭去后闭壳肌腹面的薄膜，可以观察到脏神经节及其发出的脑脏神经连索。 ? 肌肉系统 掀起内脏团和右侧的外套膜，可以看到各肌肉柱与右壳肌痕附接的情况。用镊子牵动缩足肌和伸足肌，观察斧足的走向。 实验部分: 1河蚌的形态结构和环境的关系 河蚌属淡水底栖生物，常栖于河床底部。双壳，成流线型，利于抵御水流冲击，也利于其在水底爬行;前端具一可伸缩斧状足，适于在水底掘沙;后端出、入水管口并排，体内一套完整水流循环系统，口端具唇瓣，用于激起水流，水流经过口时，河蚌取食水中的浮游生物。另外，雌河蚌外腮瓣兼具育儿囊的作用。 2软体动物门的主要特征 1、 身体分为头、足、内脏团三部分 头部:着生有口、触角、眼和其它器官。各类软体动物因生活习性不同，其头部的发达程度也不同。 足:着生在身体腹面，头的后方，有丰富的肌肉组织，是软体动物的运动器官。 内脏团:一般在足的背部，是心脏、消化、生殖等内部器官的所在部位。 2、 贝壳和外套膜 (1)贝壳 大多数软体动物身体的柔软部分外面都有贝壳，是软体动物的特征之一。不 同种类的贝壳的形态、数目各不相同，但其基本结构是相似的，都有三层结构: 角质层:为最外层，薄而透明，具黑色光泽。由外套膜边缘内侧分泌 而成。随着动物生长，面积逐渐扩大。 主要成分:壳质素 功能:保护贝壳的中、内层不被碳酸溶解。 棱柱层:也称为壳层，为中间一层，占椐贝壳的大部分。由外套膜边缘背面的细胞分泌而成，随着生长面积不断扩大，但其厚度不增加。 主要成分:棱柱形碳酸钙晶体 珍珠层:也称壳底，为最里层，有珍珠光泽。由整个外套膜外表面分 泌而成。随着生长 5to the Communications Board within the chassis to meet controlled switchboards. Operators providing communications ... If any compatibility requirements, by way of increased access-independent integrated services digital program-ice service, configurationing vol floor computer room located in the engine room. Voice communication system using a local telecommunications operator providm network, communication component) computer network systems and voice communications systems Center of information on medicaer rooom system hours, five hours Kok Kok intelligent integrated system of information system (1) cabling systems (including computation application system queued station ICU visitation system operation the system monitoring and training system call intercinformut entrance control system car library management system hours three Kok building equipment monitoring system hours four Kok omatically alarm system (containing public broadcast part) security technology prevention system security monitoring system ore autetwork, communications part) wired TV system information guide and the released system hours II Kok public security system fiimes engineering weak design including: hours a Kok information facilities system integrated wiring system (containing room n471 2. system description this t-92 intelligent building weak design construction figure set GJBT -2000 of electrical installations code for construction and acceptance of GBJ232-for computer software engineering GB/T50314 厚度不断增加。珍珠即在珍珠层内形成。珍珠的形成是外套膜对外来物的反应。 主要成分:呈水平排列的碳酸钙薄片。 (2)外套膜 外套膜是软体动物身体背侧皮肤褶皱向下延伸形成的膜性结构，是由两层上皮细胞及中间的结缔组织和肌肉纤维组成。 功能: 分泌物质形成贝壳。 外套膜围成的外套腔与多种生理功能有关:外套腔内有呼吸器官鳃 有消化、排泄、生殖器官的开口。 具有辅助呼吸作用 3、 生殖和发育 雌雄同体，雌雄异体均有;有的雌雄异形。 有体外受精，也有体内受精的。 海产种类常具有担轮幼虫(trochophore larva)和面盘幼虫(veliger larva)期(头足类例外)。 m hours four Kok information application system queued station ICU visitation system operation the system monitoring and traisyste ity monitoring system out entrance control system car library management system hours three Kok building equipment monitoringecurity system fire automatically alarm system (containing public broadcast part) security technology prevention system securblic sstem (containing room network, communications part) wired TV system information guide and the released system hours II Kok pustem description this times engineering weak design including: hours a Kok information facilities system integrated wiring sy471 2. sy-92 intelligent building weak design construction figure set GJBT -2000 of electrical installations code for construction and acceptance of GBJ232-for computer software engineering GB/T503146in the chassis to meetto the Communications Board with controlled switchboards. Operators providing communications ... If any compatibility requirements, by way of increased access-independent integrated services digital program-s operator providing voice service, configurationcationf information on medical floor computer room located in the engine room. Voice communication system using a local telecommuni(including computer room network, communication component) computer network systems and voice communications systems Center ostems ning system call intercom system hours, five hours Kok Kok intelligent integrated system of information system (1) cabling sy