Select one function of the circulatory system:

• Transport oxygen throughout the body

• Digest food

• Produce hormones

• Store fat

The circulatory system removes waste from body cells by transporting metabolic waste—like carbon dioxide—to elimination organs.

• It transports waste to the kidneys for immediate elimination.

• It delivers waste like carbon dioxide to the lungs for expulsion during breathing.

• It carries waste directly out of the body through the skin.

• It stores waste internally until the body can process it further.

What is the heart described as in the image?

• A) A solid organ

• B) A muscular, hollow organ called the body's 'pump'

• C) A lightweight organ

• D) A non-muscular organ

How much does the heart weigh according to the image?

• Less than 1 pound

• 2 pounds

• 5 pounds

• 10 pounds

Where is the heart located according to the image?

• In the abdominal cavity

• In the mediastinal cavity

• In the cranial cavity

• In the pelvic cavity

The heart is located between the lungs, behind the sternum, and above the ______.

• diaphragm

• liver

• stomach

• kidneys

What is the function of the endocardium?

The endocardium is continuous with the inside of ________.

• the heart chambers.

• the arterial walls.

• the pericardium.

• the pulmonary veins.

What is the myocardium?

Fill in the blank: The myocardium is the _______ middle layer of the heart.

• myocardial

• epicardial

• endocardial

• pericardial