Birds that fly to the tundra to nest during the summer are said to be

Migratory

Bird migration is the conventional periodically movement, often north and south along a flyway, within breeding and wintering terrains. Many varieties of bird migrate. Migration carries high costs in extinction and mortality, from poaching by people, and is motivated essentially by the availability of food.

there are mainly three domains in biological classification namely; archaea, bacteria, and eukarya.

archaea includes all the prokaryotic cells which are characterized by their lipid membranes. they have branched hydrocarbon which is attached to glycerol through an ether linkage.

bacteria includes all the prokaryotic cells, the cell membrane of which are made up of the unbranched fatty acid chain. in addition, they are attached to glycerol through an ester bond.

eukarya includes all the eukaryotic cells, that is, the cells contain a nucleus and other membrane-bound cell organelles.

they can be autotrophic as well as heterotrophic, unicellular as well as multicellular

they include kingdoms like protista, plantae, animalia, fungi et cetera.

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explanation: