Circulatory System
Major Functions
- Respiration- delivers oxygen to the cells and removing carbon dioxide from them.
- Nutrition- carries digested food substances to the cells of the body.
- Waste Removal- disposes of waste products and poisons that would harm the body if they accumulated.
- Immunity- helps protect the body from disease
- Cellular Communication- the circulatory system provides a mode of transport for hormones
- Thermoregulation- the circulatory system transports heat( can both warm and cool body)
Heart- The human heart is an organ that pumps blood throughout the body via the circulatory system, supplying oxygen and nutrients to the tissues and removing carbon dioxide and other wastes.
Artery- Arteries are blood vessels that carry blood away from the heart. Blood carried by arteries is usually highly oxygenated, having just left the lungs on its way to the body's tissue.
Vein- Veins are blood vessels that carry blood toward the heart. Most veins carry oxygenated blood from the tissues back to the heart, exceptions are the pulmonary and umbilical veins, both of which carry oxygenated blood to the heart.
Capillary- Capillaries are the smallest of the body's blood vessels. They are only one cell thick, and they are the sites of the transfer of oxygen and other nutrients from the bloodstream to other tissues in the body; they also collect carbon dioxide waste materials and fluids for return to the veins.
Components of Blood
Plasma- Plasma constitutes more than half of the blood's volume and consists mostly of water that contains dissolved salts and proteins. The major protein in plasma is albumin. Albumin helps keep fluid from leaking out of blood vessels and into tissues, and albumin binds to and carries substances such as hormones and drugs.
Red Blood Cells- Red blood cells make up about 40% of the blood's volume. Red blood cells contain hemoglobin, a protein that gives blood its red color and enables it to carry oxygen from the lungs and deliver it to all body tissues. Red blood cells carry carbon dioxide away from the tissues and back to the lungs.
White Blood Cells- There are five different types of white blood cells, which are the Neutrophils, Lymphocytes, Monocytes, Eosinophils, and Basophils.
Platelets- Platelets are cell-like particles that are smaller than red or white blood cells. Platelets are fewer in number than red blood cells, with a ratio of about 1 platelet to every 20 red blood cells. Platelets help in the clotting process by gathering at a bleeding site and clumping together to form a plug that helps seal the blood vessel. At the same time, they release substances that help promote further clotting.
Red Blood Cells- Red blood cells make up about 40% of the blood's volume. Red blood cells contain hemoglobin, a protein that gives blood its red color and enables it to carry oxygen from the lungs and deliver it to all body tissues. Red blood cells carry carbon dioxide away from the tissues and back to the lungs.
White Blood Cells- There are five different types of white blood cells, which are the Neutrophils, Lymphocytes, Monocytes, Eosinophils, and Basophils.
Platelets- Platelets are cell-like particles that are smaller than red or white blood cells. Platelets are fewer in number than red blood cells, with a ratio of about 1 platelet to every 20 red blood cells. Platelets help in the clotting process by gathering at a bleeding site and clumping together to form a plug that helps seal the blood vessel. At the same time, they release substances that help promote further clotting.
How blood clots close up a wound
Homeostasis is the body's way of stopping injured blood vessels from bleeding. Hemostasis includes clotting of the blood. Too much clotting can block blood vessels that are not bleeding. Consequently, the body has control mechanisms to limit clotting and dissolve clots that are no longer needed.
Homeostasis involves three major processes:
Homeostasis involves three major processes:
- Narrowing (constriction) of blood vessels
- Activity of cell-like blood particles that help in blood clotting (platelets)
- Activity of proteins found in blood that work with platelets to help the blood clot
How blood travels through the heart and body
As the heart beats, it pumps blood through a system of blood vessels, called the circulatory system. The vessels are elastic tubes that carry blood to every part of the body.
How it travels through the four chambers- De-oxygenated blood comes in through the veins, into the right atrium, through the bicuspid valve into right ventricle, then to the lungs and back to get oxygen and into left ventricle and then through the tricuspid valve and into left atrium and out the aorta.
How it travels through the four chambers- De-oxygenated blood comes in through the veins, into the right atrium, through the bicuspid valve into right ventricle, then to the lungs and back to get oxygen and into left ventricle and then through the tricuspid valve and into left atrium and out the aorta.
How it works with other systems
Nervous System: The nervous system is made up of the brain, spinal cord and nerves. The brain sends messages to the heart telling it to beat. The heart beat pumps blood throughout the body so that nutrients and oxygen can be brought to cells and waste can be removed.
Digestive System: The digestive system breaks down foods and takes out needed nutrients. These nutrients are put into the blood stream for the cells to use as energy. Minerals and vitamins are also put into the blood stream to strengthen bones and the immune system.
Digestive System: The digestive system breaks down foods and takes out needed nutrients. These nutrients are put into the blood stream for the cells to use as energy. Minerals and vitamins are also put into the blood stream to strengthen bones and the immune system.