Why do some animals in the savanna have long legs and long wings? a) to shield themselves from the intense heat b) to migrate when there is low food supply c) to run away from predators d) to reach the tall trees for food

during the process of dna replication, brdu can replace thymidine and incorporate into the newly synthesized dna, cell proliferation thus can be reflected in the extent of brdu incorporation.

organ system-an organ system is a group of organs that work together to perform one or more functions. each does a particular job in the body, and is made up of certain tissues.