What two functions does an exoskeleton usually have which an endoskeleton does not?

Which of the following is the most likely result of converting forestland to urban development? a.the amount of land available for lumber production decreases. b.fewer trees are needed because cities are made mainly of concrete. c.people discover more efficient ways to grow trees. d. the price of lumber goes down.

Which organisms have pharyngeal arches that develop from all three germ layers and go through the same development stages as embryos? 1.bird 2.ladybug 3.starfish 4.snake

How many chromosomes does each human cell contain? a. 23 chromosomes b. 26 chromosomes c. 43 chromosomes d. 46 chromosomes