海绵动物和刺细胞动物

1、At least 97% of all species of animals are invertebratesFeeding and protection海洋特有海洋特有两者兼有两者兼有陆上特有陆上特有海洋特有海洋特有两者兼有两者兼有扁行动物扁行动物海绵动物海绵动物有爪动物有爪动物曳鳃动物曳鳃动物缓步动物缓步动物栉水母动物栉水母动物腔肠动物腔肠动物星虫动物星虫动物线虫动物线虫动物中生动物中生动物内肛动物内肛动物缢虫动物缢虫动物线型动物线型动物颚咽动物颚咽动物纽型动物纽型动物须腕动物须腕动物苔藓动物苔藓动物动吻动物动吻动物腹毛动物腹毛动物棘皮动物棘皮动物软体动物软体动物铠甲动物铠甲动物轮虫动物

2、轮虫动物毛颚动物毛颚动物环节动物环节动物帚虫动物帚虫动物棘头动物棘头动物半索动物半索动物节肢动物节肢动物腕足动物腕足动物内肛动物内肛动物脊索动物脊索动物Traditional protostome/原口动物原口动物Deuterostome/后口动物后口动物Parazoa/侧生动物侧生动物Coelom/体腔体腔Coelomata/体腔动物体腔动物traditional phylogeny rRNA phylogeny Complex aggregations of specialized cells Cell independent and not forming true tissues Am

3、ong the structurally simplest multi-cellular animals Nearly all sponges are marine All are sessile/固着 Amazing variety of shapes, sizes, and colors 6000 species marine Numerous tiny pores (ostia/口、门-surface) Filter water - 5 times volume of its body per min Network of canals - relatively flexible ske

4、letal frame work - spongy texture Classified as the phylum Porifera or “pore bearers”多孔动物 出水孔出水孔 Specialized for function Cellular level of organizationPinacocyte/胞饮细胞Pore cellsCollar cellsOsculum/出水孔AmebocytesSpongin/海绵丝Spicules/海绵针游走细胞游走细胞 Suspension feeders: feeding on particular organic matter s

5、uspended in the water Filter feeders: passive & activeDeposit feeders - Feeding on particulate organic matter (that settles on the bottom) Asexually: branches or bud break off Sexually Gametes Not by gonads Fertilization Internal Sperm enter Development Early stage inside Parenchymula larva (pla

6、nktonic)中实幼体中实幼体Tubular sponge from the CaribbeanEncrusting sponge from HawaiiCoralline sponge at a depth of 52 m in Puerto Rico圆球海绵千姿百态的海绵世界Brown tubular sponge in Florida (red, purple, brown tubular sponges)Yellow sponge beneath AntarcticIn Hong Kong 利用浅水生物已制造出能治疗滤过性毒菌感染的海绵核苷 美国海港海洋研究所在数万种无脊椎动物和微生

7、物中寻找有用成分，迄今最大的成功就是从一种深海海绵中提取的化合物，已经进入治疗胰腺癌的临床试验。 还有人在研究用称为竹珊瑚的深海生物作为人工骨骼 朗讯公司的贝尔实验室正在研究深海海绵如何在低温下生长出强度和导光性都比光纤更好的玻璃骨架 Evolution of tissues Next level after sponge Simple swim Respond to external stimuli Specialized nerve cells Engulf prey/吞食性捕食吞食性捕食 Sea anemones, jellyfishes, corals etc. Similar par

8、ts of body/身体各部位的相似性身体各部位的相似性 No head, front or back/无头、前部、腹部区分无头、前部、腹部区分 Oral surface, aboral surface/有口面，对口面有口面，对口面 Centrally located mouth surrounded by tentacles/口位口位于中心，触手长于四周于中心，触手长于四周 Gut is a blind cavity with only one opening, mouth Polyp: sac-like attached stage （水螅型） Medusa: bell-like or

9、jellyfish, adapted for swimming （水母型）sticky or armed with a long tube that wraps around parts of prayDischarge nematocyst to capture small prey Unique stinging structure found within cells in the tentacle/触手 Consist of a fluid-filled capsule containing a thread/刺丝 that can be quickly ejected 10,000

10、species Hydrozoa/水螅纲 Scyphoza/水母纲 (Cubozoa/方水母纲方水母纲) Anthozoa/珊瑚纲Wide range of formsAttached coloniesReproduction mechanicscomplex life historiesPlanula/浮浪游体浮浪游体 Medusa is dominant stage Polyp is small，releasing juvenile medusa Round body, big size, up to 3m Limited swim ability, carried by current Dangerous marine animals Polyp lack medusa stage Gut containing several thin partitions/分隔 and septa/刚毛 Sea anemones/海葵: large, colorful polyps Corals/珊瑚:sec