The flow of energy within an ecosystem refers to

Scientist have long study the earths climate by looking at which of the following? the earths orbit. the earths rock layers. the antarctic ice. the earths oceans.

Select the correct answer. in the image, if the washcloth represents consumed food, which organ of the digestive system correctly represents the action performed by the hands? hands squeezing water from a washcloth a. esophagus b. large intestine c. liver d. mouth

The vaccine in a flu shot contains weakened flu viruses. how does a flu shot work with the immune system? a. it destroys lymphocytes. b. it destroys macrophages. c. it activates macrophages. d. it activates lymphocytes.