When the cell concentrates potassium within, against the natural tendency of matter, it is performing
a. passive diffusion
b. facilitated diffusion
c. active transport
d. pinocytosis

Which is not a characteristic of the animal kingdom? a. they include both vertebrates and invertebrates b. their skin is covered with hair or fur c. they are heterotrophs d. they are eukaryotic

Acar company is testing seatbelts using crash test dummies. the company finds that when cars come to a sudden stop, the crash test dummies' bodies continue to move forward. the seat belt keeps the crash test dummies from hitting the back of the seat in front of them. why do the crash test dummies' bodies continue to move forward even though the car stopped? a. the friction opposing their bodies' movement keeps them in motion. b. the inertia of their bodies keeps them in motion. c. the forward acceleration of the car keeps them in motion. d. the gravity pulling on the car keeps them in motion.

Plants consume most of their carbon from a. the soil b. the water c. the roots d. the air