polar – adj. of or relating to the North or South Pole or the region around it

algae – n. simple plants that have no leaves or stems and that grow in or near water

pair – n. two animals that mate together

parasite – n. an animal or plant that lives in or on another animal or plant and gets food or protection from it

mammal – n. type of animal that feeds milk to its young and that usually has hair or fur covering most of its skin

glacier – n. a very large area of ice that moves slowly down a slope or valley or over a wide area of land