'); (window.slotbydup=window.slotbydup || []).push({ id: '8096091', container: s, size: '580,90', display: 'inlay-fix' });})(); 【例】传染病的易感人群是指()。? A.对某种传染病缺免疫力而容易感染该病的人? B.没有...
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'); (window.slotbydup=window.slotbydup || []).push({ id: '8096091', container: s, size: '580,90', display: 'inlay-fix' });})(); 1、建立自然保护区是保护生物多样性最为有效的措施。我国现已建成许多保护生态系统...
'); (window.slotbydup=window.slotbydup || []).push({ id: '8096091', container: s, size: '580,90', display: 'inlay-fix' });})(); 1、目前已知的动物约150万种,按有无脊柱分为脊椎动物和无脊椎动物两大类。按生活环...
'); (window.slotbydup=window.slotbydup || []).push({ id: '8096091', container: s, size: '580,90', display: 'inlay-fix' });})(); 说明生物和生物之间有密切的联系 (1)生物的特征:生物的生活需要营养;生物能进行呼吸...
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'); (window.slotbydup=window.slotbydup || []).push({ id: '8096091', container: s, size: '580,90', display: 'inlay-fix' });})(); 生态系统 1.定义:在一定的空间范围内,生物与环境所形成的统一的整体叫生态系统。...
'); (window.slotbydup=window.slotbydup || []).push({ id: '8096091', container: s, size: '580,90', display: 'inlay-fix' });})(); 1.绿色植物的生活需要水和无机盐的原因 水在植物体内作用很大,水分充足时,植株才...