Ques: Answer the following question given this paragraph: Birds have light-weight bones that are filled with air. They also lack a jaw, which in many vertebrates is a dense, heavy bone with many teeth. Instead, birds have a light-weight keratin beak without teeth. Q: Birds have light-weight bones that are filled with what? Choices: - water - proteins - blood - air A:
Ans: air

Ques: Answer the following question given this paragraph: Unlike oxygen, carbon dioxide is more concentrated in the blood in the capillaries surrounding the alveoli than it is in the air inside the alveoli. Therefore, carbon dioxide diffuses in the opposite direction. It moves out of the blood and into the air. Q: Which gas moves from the blood in the capillaries into the air? Choices: - nitrogen - carbon monoxide - oxygen - carbon dioxide A:
Ans: carbon dioxide

Ques: Answer the following question given this paragraph: Vertebrates are chordates with a vertebral column and endoskeleton of cartilage and bone. Vertebrates also have several organ systems. Q: What is the term for chordates with a vertebral column and endoskeleton of cartilage and bone? Choices: - am - insect - mammel - vertebrate A:
Ans: vertebrate

Ques: Answer the following question given this paragraph: Secondary pollutants form from chemical reactions that occur when pollution is exposed to sunlight. Q: Secondary pollutants form from chemical reactions that occur when pollution is exposed to what? Choices: - humans - water - air - sunlight A:
Ans:
sunlight