By Israel Lara Human Anatomy and Physiology
Contributions of William Harvey on Circulatory System Harvey observations of dissected hearts showed that the heart allowed blood to flow in one direction. Harvey also theorized that arteries and veins where attached to each other by capillaries. Harvey used mathematic data to prove that the blood was being consumed. Removal of the blood from human cadavers showed that the heart could hold roughly two ounces of blood. Harvey’s lecture notes show that he believed in the role of the heart in circulation of blood through a closed system as 1615 but waited 13 years to publish his finds in his work. Harvey work became the foundation for all modern research on the hear and cardiovascular medicine.
Major Blood Vessels • Arteries- elastic vessels that transport blood away from the heart • Veins- elastic vessels that transport blood to the heart • Capillaries- are small vessels located within the tissues of the body that transport blood from the arteries to the veins • Sinusoids small vessels located within the liver, spleen and bone marrow
Blood Flow • The heart contracts and forces blood into the blood vessels, the blood moves through pulmonary circulation and then continues on through systemic circulation. Pulmonary and systemic are the two circuits in the two-circuit system of higher animals with closed circulatory systems. Blood that is lacking oxygen is said to be deoxygenated. This blood has just exchanged oxygen for carbon dioxide across cell membranes, and now contains mostly carbon dioxide. Freshly oxygenated blood returns to the heart via the pulmonary veins. Note that these are the only veins in the body that contain oxygenated blood; all other veins contain deoxygenated blood.
Comparison of the Evolution of the Vertebrate Heart • Humans, birds, and mammals have a four-chambered heart that completely separates oxygen-rich and oxygen-depleted blood • The disadvantage of the three-chambered heart is the mixing of oxygenated and deoxygenated blood. Some reptiles have partial separation of the ventricle. Other reptiles, plus, all birds and mammals, have a four-chambered heart, with complete separation of both systemic and pulmonary circuits.
pathway of blood through the heart • 1. Oxygen poor blood flows from the body into the right atrium. • 2. Blood flows through the right atrium into the right ventricle. • 3. The right ventricle pumps the bloods to the lungs where the blood releases waste gases and picks up oxygen • 4. The newly oxygen rich blood returns to the heart and enters the left atrium • 5. Blood flows through the left atrium into the left ventricle • 6. The left ventricle pumps the oxygen rich blood to all parts of the body
Inteumentary system • The skin is the largest organ in the body. Its is about 12-15% of body weight. Two distinct layers occur in the skin the dermis and epidermis. The basic type of cell type of the epidermis is the keratinocyte which contain a fibrous protein. The dermis is a connective tissue layer under the epidermis and has nerve endings, sensory receptors, capillaries and elastic fibers.
Bones in Head Region • Skull- is there to protect the brain and is located on the head. • It also helps to attach the brain and other head organs to the rest of the body by connecting to the spinal cord. • Maxilla-is located in the upper jaw • The alveolar process of the maxilla holds the upper teeth, and is referred to as the maxillary arch. The maxilla attaches laterally to the zyomatic bones
Bones In Arm Region • Elbow Joint- is a joint that connects both parts of your arm so that it can move.The elbow is a joint called the ball-and-socket joint • Shoulder Joint-This is a multiaxialball and socket type of synovial joint that permits a wide range of movement. However, mobility is gained at the expense of stability.
Bones in Mid Section region • Ribs- the ribs protect the organs. They can only react to air pressure. The ribs is to hold lungs within a closed, rigid box • Pelvis- the pelvis supports your upper body weight. Pelvis is to provide structural support as a base for the spine and connector to the legs (hips)
Bones in Leg Region • Knee Joint- the knee joint is the largest and most heavily loaded joint in the body. It connects the upper leg with the lower leg and transfers the entire weight of the body to the lower leg. • Fibula-The fibula is one of the two bones located in the lower legs of humans. The fibula is used mostly to attach muscles to. It is smaller of the lower leg bones and does not provide much support
Endocrine System • The endocrine system comprise glands that produce hormones with a varied array of vital functions. The endocrine system has influence on the way you feel and act. Hormones travel through the blood stream. The hypothalamus controls the endocrine system. The pituitary glad is called the master gland of the body. The process of maintaining normal body function through hormonal regulation is called homeostasis.