The process in which birds spread oil on their feathers using their beaks is called a. preening c. brooding b. molting d. none of the above

How does land development destroy ecosystems? it increases human carrying capacity too rapidly. it converts them into residential or agricultural areas. it forces humans to import non-native plants and animals. it expands the natural range of native wildlife species.

Which best describes red blood cells? a. they are colorless b. they protect against disease-carrying microorganisms c. they transport oxygen throughout the body d. they aid in blood clotting

Why does meiosis produce cells with half the chromosomes? o a. most of the chromosomes are not necessary to keep an organism alive. b. a gamete needs only half the number of chromosomes because two gametes join together. o c. it makes the gametes easier to move around in the organism. o d. it is faster to produce gametes with fewer chromosomes.