Which of these best explains why birds and dogs both show gills in their early development? A. Both organisms can breathe underwater.
B. Both organisms share a common ancestor.
C. Both organisms use them to process food when they are young.
D. Both organisms have different ways of forming their lungs.

The phlogiston theory in the 17th century attempted to explain burning. the theory stated that combustable objects contained a material called phlogiston, a substance without mass, color, odor, etc. after objects burned, the objects were dephlogistonated and were then in their true form. the phlogiston theory was accepted until the 18th century, when lavoisier proved that combustion requires a gas that has mass. phlogiston is considered a) to be scientific knowledge b) not to be scientific knowledge c) to be proven by scientific method d) to be accepted in the modern scientific community

Which best describes carbon dioxide’s path out of the body

Apuppy’s tendency to chew is inherited through which of the following? a. through learned behavior b.through genes c. through seasonal cycles d. through hibernation