文档介绍：第二章真核微生物Chapter 2 Eukaryotic anisms第一节真菌的一般形态第二节真菌的分类MoldsMushroomsFungi YeastsAlgaeProtozoaEukaryotic anisms真核微生物的基本特征是具有真正的细胞核,含有线粒体,不含叶绿体,化能有机营养,具有细胞壁,无根、茎、叶分化的真核微生物。真核微生物包括真菌(霉菌、酵母菌)、藻类和原生动物有明显的核。核有核膜将其与细胞质分开所有真菌都是有机营养型,藻类为无机营养型的光合生物真菌细胞都有细胞壁,细胞壁成分大都以几丁质为主,部分低等真菌细胞壁成分以纤维素为主,原生动物无细胞壁真菌大都为分枝丝状即霉菌,少数为单细胞如酵母真菌:一类低等真核生物1、具有细胞核,进行有丝分裂;2、细胞质中含有线粒体但没有叶绿体,不进行光合作用,无根、茎、叶的分化;3、以产生有性孢子和无性孢子二种形式进行繁殖;4、营养方式为化能有机营养(异养)、好氧;5、不运动(仅少数种类的游动孢子有1-2根鞭毛);6、种类繁多,形态各异、大小悬殊,细胞结构多样;Fungiare heterotrophic eukaryotic anisms. They are nonphotosynthetic and typically form reproductive . Fungi usually grow better in an acidic pH (), which is too acidic for the growth of mon bacteria. 2. Most molds are aerobic, so they grow on surfaces rather than throughout a substrate. Yeasts are facultative anaerobes. 3. Most fungi are more resistant to osmotic pressures than bacteria are; most fungi are therefore able to grow in high sugar or salt differ from bacteria in certain environmental requirements and in the following nutritional characteristics:4. Fungi are capable of growing on substances with a very low moisture content, generally too low to support the growth of . Fungi require somewhat less nitrogen for growth than . Fungi are capable of plex carbohydrates, such as lignin (wood), that most bacteria cannot of fungi2. Unicellular fungi真菌的营养体真菌细胞的结构真菌细胞示意图细胞壁(Cell wall) 原生质膜(Cytoplasm) 边体(Lomasome) 细胞核(Cell nucleus) 线粒体(Mitochondria) 核蛋白体(Nucleoprotein) 内质网(Endoplasmic reticulum) 高尔基体(Golgi body)真菌细胞壁厚约100~250nm,占细胞干物质的30% 主要成分为己糖或氨基己糖构成的多糖链,如几丁质、脱乙酰几丁质、纤维素、葡聚糖、甘露聚糖,还有蛋白质、类脂、无机盐等菌龄和外界环境因素强烈影响真菌细胞壁的成分在衰老的菌丝和孢子表面长出现一些附加物,最常见的是黑色素和脂肪。黑色素为酚化合物经氧化和聚合而产生的,后进入细胞壁。脂肪聚集在细胞壁内层