Lungs serve the purpose of gas exchange. we inhale air, drawing in oxygen (o2) and exhale air, expelling carbon dioxide (co2). this is done across thin-walled pockets of cells called alveoli. because body cells consume o2 and generate co2, concentrations of co2 and o2 are higher and lower, respectively, at alveoli surfaces than they are in adjacent capillaries. both of these molecules are small, and freely pass through membrane bilayers. based on this information, the movement of o2 from the alveoli of the lungs into the bloodstream is an example of

How do accessory pigments chlorophyll?

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.

The nervous system interacts with the endocrine system by a. using hormones as connections b. sending nerve impulses directly to glands c. using neuroendocrine cells as connections d. sending neurotransmitters directly to neurons