Alllivingorganisms,regardlessoftheiruniqueidentity,havecertainbiological,chemical,andphysicalcharacteristicsincommon.
A、asaresultofThefuturesurvivalofthebaldeagleisstillanimportantAmericanecologicalconcern.
Thewheelsofthefirstroadvehicleswerefashionedfromcrudestonedisks.
In1974HenryAaronbrokeBabeRuth'smonumentallifetimerecordof714homeruns.
Foodmustbemoistinordertohaveataste.
Eyespots,themostrudimentaryeyes,arefoundinprotozoan原生動(dòng)物flagellates鞭毛蟲(chóng),flatworms扁形蟲(chóng),andsegmentedworms片段蠕蟲(chóng).