The Circulatory System
No cell is further than that carries nutrients. Your circulatory system km of blood vessels. Your heart beats about from the beginning of life until death. During an average lifetime, the heart pumps enough blood to fill.
Your circulatory system: - carries - from cells - from cells in one part of the body to. - distributes throughout the body - along with the kidneys, maintains acceptable - helps defend against
Single-celled organisms have because oxygen can into them from the surrounding. Simple multicellular organisms, have as their, remain in contact with an at all times.
Complex multicellular animals, have. The middle cell layer ( layer), is sandwiched between the and and does not come into direct contact with. Cells of the need a circulatory system. Open and Closed Circulatory Systems In an, blood is pumped into where it. This found in snails, insects, and crustaceans. In a, the blood is always. This system, commonly found in earthworms, squids, octopuses, and vertebrates,
The average person contains. Approximately ; the remaining. The percentage of in the blood is called the, is about. The also contains blood proteins, glucose, vitamins, minerals, dissolved gases, and waste.
Erythrocytes The primary function of, is the transport of oxygen. Mature. Instead they contain molecules of. Hemoglobin is composed of, the iron-containing pigment, and, the protein structure. attach to the folded protein and. The gives blood its red colour. has a different shape, causing the reflection of. This explains why blood appears.
Red blood cells appear This shape provides a for gas exchange RBC live Formed, by nucleated stem cells. Young as they are discharged into the blood stream.
Leukocytes - White blood cells,, are much than red blood cells. - RBC:WBC. - White blood cells. - The of the nucleus, along with the, used to identify different. - WBC help protect the
are classified according to that become visible when stained. BASOPHILS - NEUTROPHILS - EOSINOPHILS - are white blood cells that do not have a. These are known. LYMPHOCYTES - MONOCYTES - All WBC produced in the, but are modified in the.
Appearance
Platelets Platelets, like RBCs, do not contain. Small fragments break from the. Platelets move through the of the body but rupture if they. This is how the fragile platelets initiate
Blood Groups Special markers are located on the. Individuals with blood type A have the A marker attached to their cell membrane. Blood type B have Blood type AB have. Those with blood type O have. Blood types are important if blood. (Blood Transfusion) For example: If type A blood is transfused into a type O individual, special proteins, The A-type protein acts as an The antibodies attach themselves to the A-type proteins and cause them to. The clumped cells leading to
The after antibody attachment is called. What about the others?
During the 1940s, scientists discovered on the red blood cell: the. Individuals who have the are said to be. Those who do not are. Individuals who are may donate blood to individuals, but.
ARTERIES Blood Vessels Arteries carry blood They composed of distinct layers. The outer and inner layers are. Middle layers are made up of. Every time the heart contracts,. Your pulse is created by changes in the following heart contractions. Blood from the arteries passes into. The, regulates the diameter of the arterioles. When arterioles contract, it is called.. Relaxation of the arterioles, increases blood flow and is called..
helps the body release that is produced when you become diverts blood away from the outer capillaries of the skin toward the. The blood flow to the muscles provides for energy to meet the demands of a response to a.
Arteries are composed of 3 coats or TUNICS TUNICA Lines the interior of the vessel Composed of (like skin), tissue and some elastic tissue TUNICA Bulky middle coat, made mainly of tissue TUNICA Mainly made of tissue for support and protection
Fat in the Arteries: Fat droplets in your blood can into larger and larger. They slowly close off the. and other minerals deposit on top of the lipid, forming a. This condition is known as. This can the artery to of its original and lead to. can form around the fat deposits.
Capillaries After blood passes through muscles into the smallest blood vessels,. The diameter is so small that must travel through. Capillary beds. or any impact,can the thin-layered
Veins Capillaries become larger vessels, called The walls contain. merge into. The return blood to the heart. Because pressure in veins is to drive the blood you have evolved 2 additional mechanisms to help: 1. - One way prevent blood from flowing 2. - when below your heart (legs) they create and force back toward the heart.
The Mammalian Heart The heart consists of separated by the. The pump on the receives tissues and pumps it to. The pump on the from the and pumps it to the. Vessels that carry blood to and from the lungs comprise the Vessels that carry blood to and from the body comprise the
One-Way Blood Flow Blood flows back to the heart through veins. 1. Blood enters the heart through ( blood from above ), and through the (blood from below the ) into the. 2. Blood next passes through a ( valve) into the
3. Blood then passes through the into the which splits into the on it's way to the lungs. 4. Blood returns from the lungs through the into the 5. Blood then travels through an and into the. 6. Blood is forced out of the heart through the into the
HEART BEAT Your heart beat begins with an originating in a small patch of tissue in the called the This causes the. At the same time the impulse travels to the The acts as a,, passing the impulse via two through the toward the, which in turn causes both.
The change in as the heart beats can be measured using an P wave - QRS wave - T wave - Repolarization of the atria.
Changing Heart Rate
The term refers to the events of one complete. The last approximately. When a healthy heart beats, the, then as they begin to relax. mean heart contraction and relaxation. Since the do most the work in the heart, the above terms refer to The cardiac cycle can be broken down into 3 parts: A. B. C.
A. Heart begins in in the heart is low Blood flows into the atria The atria then and push blood into the
B. Ventricular Pressure Blood rushes out of are relaxed and refilling with blood
C. Ventricles relax Ventricles begin The HEART SOUNDS are often described by two syllables: Abnormal or unusual heart sounds are called