Which of these is a characteristic of index fossils? Found in the topmost rock layer
Found in many layers of the same rock
Have already established relative age
Are limited to a particular geographic location

Which statement describes an endocrine function rather than an exocrine function? a. salivary glands release saliva into the mouth. b. sweat glands release sweat onto the skin c. the pineal gland releases melatonin into the blood. d. esophageal glands release mucus into the esophagus.

In the water cycle , when does water undergo a chemical change

Is there any species that went extinct in recent years due to natural causes (not caused by human interaction). if so, what caused it?