Summarize the relationship among fossils, rock layers, and the divisions of the geological time scale.

Sand spinifex grass is adapted to growing on sand dunes. it is a rapidly spreading plant and the creeping runners produce new root systems. which of these best explains the benefits of these features? a. it limits water loss through the leaves. b. it provides support by anchoring the plant. c. it protects the plant from predators. d. it allows the plant to tolerate salt. reset submit

Read the following scenario to answer the following question. in some zoos, rare crosses between a male lion and a female tiger have produced hybrid offspring called "ligers." male ligers are sterile but some female ligers are fertile. in the wild, lion and tiger ranges do not naturally overlap, making such a cross unlikely. furthermore, the solitary behavior of tigers and the social organizations of lions create behavioral differences. applying the biological species concept, the sterility of ligers reveals that a. lions are probably a subspecies of tigers b. tigers and lions are the same species c. a new species called "ligers" is forming d. tigers and lions are separate species

Define the apical impulse and describe its normal location, size, and duration. which abnormal conditions may affect the location of the apical impulse? explain the mechanism producing normal first and second heart sounds. describe the effect of respiration on the heart sounds. describe the characteristics of the first heart sound and its intensity at the apex of the heart and at the base. describe the characteristics of the second heart sound and its intensity at the apex of the heart and at the base.