The Circulatory System Flashcards
What is the purpose of the circulatory system?
Facilitates the transport of materials within the internal environment for exchange with cells through structure and function.
What is the purpose of the lymphatic system?
To collect escaped fluid from blood capillaries and return it to the circulatory system.
Plays an important role in the body’s internal defense and resistance against disease-causing organisms.
What are the main components of the circulatory system?
The heart, blood vessels, blood, the chambers, the valves.
What is the function of the blood vessels?
Blood is pumped by the heart into the blood vessels, which carry the blood to the cells of the body/lungs and bring it back to the heart again.
- Deliver oxygen and nutrients to cells
- Carry away waste products from cells
- Part of maintaining blood pressure
What is the function of blood?
- Transport
- Regulation
- Protection
How does the blood provide transport?
Transports nutrients and oxygen to all cells of the body as well as transporting carbon dioxide and other waste products away from the cells.
It transports chemical messengers, called hormones to the cells.
How does the blood provide regulation?
It distributes heat to help in regulating the body’s temperature and pH of body fluids
How does the blood provide protection?
Prevents blood loss by clotting if blood vessels are damaged. It also protects the body against pathogens, toxins and disease-causing micro-organisms.
What is the function of the right side of the heart?
The right side of the heart makes up the pulmonary circuit. It collects deoxygenated from the heart and pumps it into the lungs
What is the function of the left side of the heart?
It makes up the systemic circuit. It receives oxygenated blood from the lungs and pumps it to the rest of the body.
What is the right atrium?
The receiving chamber for deoxygenated blood that has been through the capillaries of the body.
What is the function of the right ventricle?
Pumps blood to the lungs. Its wall is thinner that the left ventricle wall because not as much force is required to push blood to the lungs.
What is the left atrium?
The receiving chamber for blood from the lungs. Pushes blood into the left ventricle
What is the left ventricle?
Has a thick muscular wall for pumping blood into the aorta and out the body.
What is the pulmonary trunk?
Divides into two pulmonary arteries that carry deoxygenated blood to each lung.
What is the function of semilunar valves?
Prevent backflow of blood from arteries to ventricles.
What is the function of the pulmonary vein?
Brings oxygenated blood to the heart from the lungs
What are the atrioventricular valves?
- Between the atria and the ventricle.
- Flaps of thin tissue with the edges held by tendons called chordae tendinae.
- Prevents backflow of blood from the ventricles to the atria
How does blood become deoxygenated?
As oxygenated blood flows through the capillaries of the body, oxygen and nutrients diffuse from the blood into the body cells, and carbon dioxide and other wastes diffuse from the cells and into the blood, becoming deoxygenated.
How does blood become oxygenated?
As deoxygenated blood flows through the capillaries of the lungs, oxygen diffuses from the air into the blood and carbon dioxide diffuses from the blood into the air, becoming oxygenated.
What are the main components of blood?
- Plasma (55%)
- Erythrocytes (RBCs - 41%)
- Leucocytes (WBCs)
- Thrombocytes (Platelets)
What is plasma?
A mixture of water with dissolved substances such as sugar and salts.
What is the function of plasma?
To transport components of blood, including cells, nutrients, wastes, hormones, proteins and antibodies throughout the body.
What are erythrocytes?
- Account for approximately 40-45% of its volume.
- Biconcave shape – flattened in the middle on both sides.
- Don’t contain a nucleus increasing their flexibility and ability to move through blood vessels.
- The lack of a nucleus limits their life span to only 120 days on average.