Question 1
Multiple ChoiceWhich body system is primarily responsible for transporting blood, oxygen, and nutrients throughout the body?
Explanation
The circulatory (cardiovascular) system moves blood through the heart and blood vessels, delivering oxygen and nutrients and carrying away wastes.
Question 2
Multiple ChoiceWhich organ pumps blood throughout the body?
Explanation
The heart is a muscular organ that pumps blood through the circulatory system.
Question 3
Multiple ChoiceWhat is the main function of the respiratory system?
Explanation
The respiratory system carries out gas exchange — taking in oxygen and releasing carbon dioxide, mainly in the lungs.
Question 4
Multiple ChoiceWhich system is responsible for breaking down food into nutrients the body can absorb?
Explanation
The digestive system breaks down food mechanically and chemically so nutrients can be absorbed and wastes eliminated.
Question 5
Multiple ChoiceWhich system controls and coordinates the body's activities by sending electrical signals?
Explanation
The nervous system — the brain, spinal cord, and nerves — controls and coordinates body functions using electrical and chemical signals.
Question 6
Multiple ChoiceWhat is the largest organ of the human body?
Explanation
The skin is the body's largest organ. It protects the body, helps regulate temperature, and provides the sense of touch.
Question 7
Multiple ChoiceApproximately how many bones are in the adult human body?
Explanation
The adult human skeleton has 206 bones. Babies are born with more, and some fuse together as they grow.
Question 8
True FalseOne of the main jobs of the skeletal system is to support the body and protect internal organs.
Explanation
The skeletal system supports the body, gives it shape, allows movement, and protects organs such as the brain, heart, and lungs.
Question 9
True FalseThe primary role of the lungs is to pump blood to the rest of the body.
Explanation
This is false. The lungs are organs of the respiratory system where gas exchange occurs. It is the heart that pumps blood.
Question 10
Multiple SelectWhich of the following are functions of the nervous system, especially the brain? (Select all that apply.)
Explanation
The brain and nervous system process sensory information, control thoughts and memory, and coordinate movement. Producing red blood cells is a function of bone marrow, not the nervous system.