SBI3U Chapter 12.1 The Function of Circulation

T/F - In single-celled organisms such as an amoeba, nutrients and respiratory gases enter the cell and waste materials leave the cell by diffusion and other cellular processes. Thus, single-celled organisms exchange matter directly with the outside environment.

• True

• False

Which of the following statements about the "main functions of the circulatory system" is INCORRECT.

• It transports gases (from the respiratory system), nutrient molecules, and waste materials (from the digestive system).

• It regulates internal temperature and transports chemical substances that are vital to health from one part of the body to the other.

• It protects against blood loss from injury and against disease-causing microbes or toxic substances introduced into the body

• None of the other of the 3 are INCORRECT.

T/F - The circulatory system has two major components: the heart and the blood vessels

• True

• False

Which of the following statements about an "open circulatory system" is INCORRECT.

• Many invertebrates have an open circulatory system.

• The system is called “open” because blood flows freely within the body cavity and makes direct contact with organs and tissues.

• The mixture of blood and fluids that surrounds the cells is called hemolymph.

• Nutrients and wastes are exchanged between the hemolymph and cells in the heart chambers before the hemolymph passes back into the transporting vessel to be eliminated from the insect’s body

• None of the other 4 choices are INCORRECT

T/F - Animals, such as all vertebrates, earthworms, squid, and octopus, used a closed circulatory system to circulate the blood, keep it under pressure, and pump it at a speed sufficient to supply the metabolic needs of all parts of the body.

• True

• False

T/F - In a closed circulatory system the blood physically contained within vessels and separate from other body tissues. The blood follows a continuous fixed path of circulation and is confined to a network of vessels that keeps the blood separate from the interstitial fluid.

• True

• False

Which of the following statements about the "human heart" are INCORRECT.

• It is located slightly to the left of the middle of the chest and is about the size of your fist.

• The walls of the heart are made of a unique type of muscle called cardiac where the muscle cells are arranged in a network that allows the heart to contract and relax rhythmically and involuntarily without becoming fatigued.

• In addition to pumping blood, a healthy heart also ensures that blood keeps fl owing in one direction only, and that oxygen-rich blood is kept separate from oxygen-poor blood.

• None of the other 3 are INCORRECT.

The human heart, like the hearts of all mammals and birds, has _______ chambers.

• 1

• 2

• 4

• 6

Which of the following statements about the "human heart" are INCORRECT.

• The human heart, like the hearts of all mammals and birds, has four chambers

• The two top chambers called the atria (singular atrium), fill with blood returning from the body or the lungs.

• The two bottom chambers called the ventricles, receive blood from the atria and pump it out to the body or the lungs.

• None of the other 3 statements are INCORRECT.

Which of the following statements about "The Four Chambers of the Heart" are INCORRECT.

• The right side of the heart receives blood that is coming back from the body, and then pumps this blood out to the lungs.

• The left side of the heart receives oxygen-rich blood from the left and right lungs and pumps this blood out to the body.

• Two large vessels, called the vena cavae (singular vena cava), collects oxygen-poor blood coming from the tissues of the body.

• All oxygen rich blood going to the body tissues leaves through the largest vessel in the body, the aorta.

• None of the other 4 statements are INCORRECT.