Two main functions of the circulatory system:
Transport nutrients, wastes, and oxygen through the body.
To fight disease/infection in the body.
Blood is a connective tissue that carries oxygen, nutrients, carbon dioxide, and other wastes throughout the body.
It is made up of four main cells.
Red Blood Cells
White Blood Cells
Platelets
Plasma
The Circulatory system works with ALL of the other systems in your body. It connects EVERYTHING together.
Villi of the small intestines absorb nutrients from food and pass them into the blood within capillaries so they can be transported to the rest of the body for cellular respiration.
The alveoli of the lungs are surrounded by capillaries so that carbon dioxide and oxygen can be exchanged. Carbon dioxide diffuses from the blood into the alveolar space. Oxygen diffuses from the alveolar space into the blood.
Blood picks up waste products (water, urea, salt) from every cell in the body and carries those wastes to the kidneys to be filtered and removed from the body as urine.
Blood is made in the bone marrow
The heart is made of cardiac muscle tissue.
Veins and arteries have a layer of smooth muscle tissue between the connective and epithelial tissue layers.
The heart pumps blood and nutrients to the brain to allow it to keep functioning. The brain sends electrical impulses to the heart telling it to keep pumping.