笨蝗Haplotropis brunneriana消化道结构研究

发布时间：2018-03-26 01:04

本文选题：笨蝗　切入点：消化道　出处：《山西师范大学》2015年硕士论文

【摘要】：本文利用体视显微镜、光学显微镜、扫描电镜和透射电镜技术对笨蝗Haplotropisbrunneriana Saussure消化道结构进行了研究，比较分析了前肠、中肠和后肠在形态学、组织学和细胞学3个方面的结构特点，并探讨了其结构与功能的关系，旨在为揭示笨蝗消化道结构的特异性，为昆虫分类学及消化系统的演化提供基础资料。笨蝗消化道由前肠、中肠和后肠3部分组成。前肠包括细管状的食道、膨大呈囊状的嗉囔和杯状的前胃，中肠包括一段短而直的管状胃和6对锥形的胃盲囊，胃盲囊位于前胃和胃之间，由胃前端向外突起形成。后肠由回肠、结肠和直肠组成，回肠前端膨大为囊状向后逐渐变细为结肠，然后膨大呈纺锤状的直肠。在前胃内壁末端有6个Y形贲门瓣，回肠内壁前端有12个棒状幽门瓣。笨蝗前肠、中肠和后肠的组织结构存在差异。前肠内表面有角质化程度较高的内膜，上皮层由排列紧密的单层柱状上皮细胞构成，，上皮层外分布为肌肉层，环肌排列在外侧，纵肌排列在内侧。中肠无内膜，柱状上皮细胞顶端分布有大量微绒毛，肌肉排列与前肠刚好相反。后肠结构与前肠基本相似，只是内膜层厚度与肌肉发达程度不同。扫描电子显微镜研究发现，笨蝗前肠和后肠内壁均有齿分布，中肠无齿。前肠主要以单生齿分布为主，食道上为单生齿和双生齿，嗉囊壁内褶成脊，脊上均为单生齿，前胃齿特化，Y形贲门瓣长臂两侧的单生齿齿尖左右咬合，短臂上有单生尖齿和钝齿。中肠内表面具有丰富的微绒毛。后肠幽门瓣上双生齿最多，丛生齿次之，单生齿极少；回肠和直肠垫上均无齿，分布有筛网状结构；结肠内表面分布较多的丛生齿；直肠垫之间的内壁上有齿，齿尖垂直于消化道纵轴。笨蝗前肠上皮细胞中含有较多的线粒体和粗面内质网，端部有微绒毛分布，这些结构特点说明上皮细胞可能参与了内膜层的形成。后肠的超微结构与前肠相似，显著的特征是上皮细胞基部含有大量的空泡和不同大小的电子密度颗粒，这些结构可能与后肠回收水分和无机盐相关。前胃盲囊和后胃盲囊的超微结构具有相似的特点。上皮细胞顶膜特化形成大量细长的微绒毛，微绒毛周围附着有酶原粒。上皮细胞顶端有局部胞吐和全胞胞吐现象。顶端胞质中分布有丰富的微粒、线粒体、粗面内质网和一些吞噬泡。后胃盲囊与前胃盲囊的区别在于二者上皮细胞质中存在不同电子密度的球状结构。胃上皮细胞超微结构与前后胃盲囊相似，胞吐现象仅出现在胃前段，胃后段上皮细胞基部有多泡体结构。中肠为消化吸收的主要场所。
[Abstract]:The digestive tract structure of Haplotropisbrunneriana Saussure was studied by stereoscopic microscope, optical microscope, scanning electron microscope and transmission electron microscope. The morphology of foregut, midgut and hindgut were compared and analyzed. The relationship between structure and function was discussed in order to reveal the specificity of digestive tract structure and provide basic data for insect taxonomy and the evolution of digestive system. The digestive tract is composed of three parts: foregut, midgut and hindgut. The foregut consists of a thin tubular esophagus, a bursal crop and a goblet forestomach. The midgut consists of a short, straight tubular stomach and 6 pairs of conical gastric blind sac. The gastric caecum is located between the anterior stomach and the stomach and is formed by the protuberance of the anterior end of the stomach. The posterior intestine is composed of the ileum, colon and rectum. At the end of the anterior gastric wall, there were 6 Y-shaped cardia valves and 12 rod-shaped pyloric valves at the anterior end of the ileum wall. There were differences in the structure of foregut, midgut and hindgut. There was a high degree of keratinization on the inner surface of the foregut. The epithelium was composed of a single layer of columnar epithelial cells, and the outer layer of epithelium was a muscular layer, and the circular muscle was arranged on the lateral side. Longitudinal muscles were arranged in the medial side. There was no intima in the midgut and a large number of microvilli were distributed at the top of the columnar epithelial cells. The muscle arrangement was just opposite to that of the foregut. The results of scanning electron microscope showed that the inner wall of foregut and hindgut of Locust locust had tooth distribution, but the midgut had no teeth. The main distribution of anterior intestine was single tooth, the esophagus was single tooth and double tooth, the crop wall was ridged, and the upper ridge was single tooth. The single teeth on both sides of the long arm of the forestomach teeth were special and Y-shaped cardia valves had left and right occlusal teeth, and on the short arms there were single sharp teeth and blunt teeth. There were abundant microvilli on the inner surface of the midgut, and the double teeth on the pyloric valve of the hindgut were the most, followed by the tufts, and the single teeth were rare. The ileum and rectum mats have no teeth and have ethmoidal reticular structure; the inner surface of the colon has more clustered teeth; the inner wall of the rectum pad has teeth on the inner wall and the cusp is perpendicular to the longitudinal axis of the digestive tract. There were more mitochondria and rough endoplasmic reticulum in the epithelial cells of the foregut, and the microvilli were distributed at the tip. These structural features suggested that the epithelial cells might be involved in the formation of the intimal layer, and the ultrastructure of the hindgut was similar to that of the foregut. The prominent feature is that the epithelial cell base contains a large number of vacuoles and electron density particles of different sizes. These structures may be related to the recovery of water and inorganic salts in the hindgut. The ultrastructure of the anterior gastric caecal sac and the posterior gastric caecal sac have similar characteristics. A large number of slender microvilli are formed by the specialization of the apical membrane of the epithelial cells. The microvilli are surrounded by enzyme granulocytes. There are local exocytosis and whole cell exocytosis at the top of the epithelial cells. There are abundant particles, mitochondria, and mitochondria in the apical cytoplasm. Rough endoplasmic reticulum and some phagocytic vesicles. The difference between the posterior gastric caecum and the anterior gastric caecum lies in the existence of different electron density spherical structures in the cytoplasm of their epithelium. The ultrastructure of gastric epithelial cells is similar to that of the anterior and posterior gastric caecal sac. Exocytosis occurred only in the anterior part of the stomach, and there were many vesicles at the base of the epithelial cells in the posterior segment of the stomach, and the midgut was the main place for digestion and absorption.
【学位授予单位】：山西师范大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：S433.2

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