Your cardiovascular system

Quick facts:

Your heart, blood vessels, and blood together form your cardiovascular system: a system that pumps and transports life supporting nutrients to tissues throughout your body.

This system is also essential for removal of metabolic waste products.

Functions:

• transports nutrients from digestion from your gastrointestinal tract to your tissues and organs within your body
• transports proteins and hormones synthesised inside your body between tissues
• transports waste products from tissues and organs to your kidneys and gastrointestinal tract for excretion

Your heart

• cardiac muscle that pumps blood throughout your body
• approximately the size of your clenched fist
• comprised of 4 compartments: 2 atria and 2 ventricles
• right ventricle pumps low oxygen blood to your lungs
• left ventricle pumps oxygenated blood to all other systems in your body
• rhythmic contractions of your heart muscle pump blood out of the chambers
• pressure created in your arteries as your ventricles contract stretches your arteries creating a pulse

Blood vessels

• arteries, arterioles, capillaries, venules and veins
• arteries carry blood from your heart through your arterioles and to capillary beds
• exchange of oxygen, nutrients and other materials occurs in your capillary beds
• blood from capillaries passes through venules and then through veins which return blood back to the right side of your heart

To learn more about blood vessels and passage of blood through your body link to the full article.

A specialised system

• blood is delivered to your digestive system via an artery and then capillaries
• blood leaving your digestive system, unlike blood from other tissues, is not directed to your heart. Instead blood enters your portal vein which carries blood to your liver.
• your liver protects your body against ingested and absorbed substances (toxins, bacteria, drugs, alcohol, pesticide residues and contaminants) which may harm your body
• purified blood leaves your liver via your hepatic vein which carries your blood to your heart

Lymphatic system

• passes fluid from the spaces between your body cells to your circulatory system
• by passes your liver
• lymph nodes containing white blood cells filter lymph and fight viral and bacterial infections

 Blood

• connective tissue which consists of several kinds of cells suspended in plasma
• 4-6 litres of blood in your body
• blood plasma composed of approximately 90% water in which inorganic salts or electrolytes are dissolved as ions
• plasma also contains proteins such as lipoproteins (transport fat), antibodies (immunoglobulins), and clotting factors (fibrinogens)
• metabolic waste, nutrients, hormones and respiratory gases are also components of plasma

Cellular components

• Red blood cells, white blood cells and platelets are the cellular components of your blood.

To learn more about blood and its cellular components link to the full article.