See acetylcholine.參閱4頁(yè)acetylcholine。...[繼續(xù)閱讀]

    A dry indehiscent fruit formed froma monocarpellary ovary containing a singleseed. Different types of achenes include thecaryopsis,cypsela,nut,and samara. Seealso etaerio.由內(nèi)含一粒種子的單心皮子房形成的不開(kāi)裂干果。不同類(lèi)型的瘦果包括穎果、連萼瘦果、堅(jiān)果和翼果...[繼續(xù)閱讀]

    A substance that gives rise to hydro-gen ions (or H3O+) when dissolved in wa-ter. An acid in solution will have a pH below7.This definition does not take into accountthe competitive behavior of acids in solventsand it refers only to aqueous systems. TheLo...[繼續(xù)閱讀]

    Maintenance of the optimum pH of body fluids by regulating theacid; base ratio. This usually involves abuffer system (see buffer). For examplemammalian blood must be maintained at apH of7.4,which requires a ratio of carbonicacid to bicarbonate of 1∶20; an...[繼續(xù)閱讀]

    See staining.參閱773頁(yè) staining。...[繼續(xù)閱讀]

    The deposition of acids by natu-ral precipitation (e. g. rain,snow,fog),leading to acid pollution. The very diluteacids are formed by reaction of gaseous wasteproducts (e. g. sulfur dioxide,nitrogen ox-ide ,or carbon monoxide ),with moisturepresent in the...[繼續(xù)閱讀]

    A measure of the free acid pre-sent in fats,oils,resins,plasticizers,andsolvents,defined as the number of milligramsof potassium hydroxide required to neutralizethe free acids in one gram of the substance.測(cè)量脂肪、油脂、樹(shù)脂、可塑劑、溶劑中游離酸含量的值。其數(shù)值為中和...[繼續(xù)閱讀]

    See auditory nerve. 參閱66頁(yè) auditory nerve。...[繼續(xù)閱讀]

    A system found in fish and certain amphibians consisting ofthe neuromast cells in various tracts on ornear the surface of the body (i.e. the later-al-line system) and the inner ear (membra-nous labyrinth ). Neuromasts and receptorcells of the inner ear ar...[繼續(xù)閱讀]

    Changes in thestructure or function of an organ or systemduring the life of an organism,brought aboutby the use or disuse of that organ or system,or by environmental influences. For exam-ple,sportsmen may develop strong muscles,and plants growing near coa...[繼續(xù)閱讀]