Module 5 Section 1

Question 1

Describe the main functions of the circulatory system.

Answer 1

The circulatory system is responsible for the transportation of materials upon which cells throughout the body are vitally dependent.

The heart
- Is the pump that generates the pressure necessary to move blood throughout the circulatory system.

The blood vessels
- Are the conduits through which the blood passes to deliver nutrients to cells and carry their metabolic wastes away.

The blood
- Is the transport media in which materials are moved throughout the body. Everything is either dissolved in, suspended in, or bound within the blood for long distance movement.

Functions:

1) Gas exchange: delivery of O2, removal of CO2
2) Nutrient and water delivery and absorption: by cells
3) Removal of heat and metabolic waste: exercising muscle generates excess heat and the constant supply of fresh blood flowing through the muscle can help remove this heat as well as metabolic wastes
4) Immunity and defense: the blood transports key immune cells that can quickly identify and neutralize foreign particles
5) Cell communication: cells from one part of the body can communicate with other more distant cells by releasing chemical messages into the blood.

Question 2

Describe how oxygenated and deoxygenated blood flows through the heart.

Answer 2

1) The heart pumps oxygenated blood out of the left ventricle and into the aorta to begin systemic circulation.
2) After the blood has supplied cells throughout the body with oxygen and nutrients, it returns deoxygenated blood to the right atrium of the heart.
3) The deoxygenated blood shoots down from the right atrium to the right ventricle.
4) The heart then pumps it out of the right ventricle and into the pulmonary arteries to begin pulmonary circulation.
5) The blood moves to the lungs, exchanges carbon dioxide for oxygen, and returns to the left atrium.
6) The oxygenated blood shoots from the left atrium to the left ventricle below, to begin systemic circulation again.

Question 3

Explain what is meant by “the systemic circulation delivers blood in parallel.”

Answer 3

The 2 circulation systems are the pulmonary circulatory system, which moves blood to and from the lungs, and the systemic circulatory system, which moves blood throughout the rest of the body.

Blood that leaves the left side of the heart flows through the systemic circulation into the right side of the heart. It then flows into the lungs before returning to the left side of the heart.

When blood leaves the left side of the heart, it flows through branching blood vessels which direct the blood to all the tissues and organs of the body simultaneously. After leaving these tissues and organs, these branched blood vessels come back together to deliver all of the blood back to the right side of the heart.

Question 4

Indicate whether each term is a function of the circulatory system or not:

• cell communication
• digestion
• water absorption
• storage of WBC
• nutrient delivery
• nutrient breakdown
• immunity
• gas exchange
• removal of metabolic wastes
• production of WBC
• heart dissipation
• production of insulin
• detoxification

Is a function of the circulatory system:

Is NOT a function of the circulatory system:

Answer 4

Is a function of the circulatory system:

• cell communication
• water absorption
• nutrient delivery
• immunity
• gas exchange
• removal of metabolic wastes
• heart dissipation

Is NOT a function of the circulatory system:

• digestion
• storage of WBC
• nutrient breakdown
• production of WBC
• production of insulin
• detoxification