Bio 101 Bio 101 Chapter 5 Circulation and

Bio 101

Bio 101 Chapter 5: Circulation and Cardovascular Systems

Lesson NO 5 Transport in Vertebrates Ø All vertebrate animals have a closed circulatory system, which is called a cardiovascular system, it consists of a heart, vessels and blood. Ø There are 3 kinds of blood vessels: 1 - Arteries : Which carry blood away from the heart. 2 - Capillaries : Which exchange materials with tissue fluid 3 - Veins : Which return blood to the heart.

Lesson NO 5 Transport in Humans The heart has 4 chambers 1. The 2 upper thin walled called Atria 2. The 2 lower chambers are thick walled called Ventricles, which pump the blood. 3. The heart also has 4 valves, which direct the flow of blood and prevent its backward movement. 4. The Pulmonary valve lies between the right ventricle and the pulmonary trunk. 5. The aortic valve lies between the left ventricle and the aorta.

Lesson NO 5

Lesson NO 5 Path of Blood through the Heart https: //www. youtube. com/watch? v=BEWj. OCVEN 7 M https: //youtu. be/d. Hqx. LZ 9 -Zj 0

Lesson NO 5 Vascular Pathway The human cardiovascular system includes two major circular pathways: 1. The pulmonary circuit 2. Systemic circuit The heart beats The normal average human heart beats are about 70 times par minute.

Lesson NO 5 Functions of the blood 1. Transports gases, nutrients, waste products and hormones throughout the body. 2. Destory microorganisms. 3. Distributes antibodies (immunity) 4. Maintaining water and p. H balance (7. 4). 5. Regulate body temperature. 6. Carries platelets and clotting factors. In humans, Blood has 2 main portions: 1. The liquid portion, called plasma. (Plasma contains, nutrients, wastes, salts and proteins. 2. The formed elements, -Red Blood Cells (erythrocytes) -White Blood Cells (Leukocytes) -Platelets (Thromboctes)

Lesson NO 5 1 - Red Blood Cells (erythrocytes) • Red blood cells are small, biconcave disk. • At maturity they lack a nucleus, their life span about 120 days. • They contain Hemoglobin, which carries oxygen or carbon dioxide. • If there is an insufficient number of red blood cells or if the cells do not have enough hemoglobin, the individual suffers from animia and has a tired, run down feeling. • They are produced by the red bone marrow of the skull, the ribs, the vertebrae and the end of the long bones.

Lesson NO 5 2 - White Blood Cells (Leukocytes) - White blood cells are usually larger, have a nucleus and they lack hemoglobin - The function: Defense against disease Types of WBC 1 - Neutrophils and monocytes are phagocytic and are very active during the inflammatory reaction. 2 - Lymphocytes are involved in the developments of immunity to disease. 3 - Eosinophils are important in allergic reaction and parasitic infections 4 - Basophils contain the anticoagulant heparin.

Lesson NO 5 3 - Platelets (Thromboctes) - Platelets result from fragmentation of certain large cells, called megakaryocytes, in the red bone marrow. - The blood contains 150, 000 – 300, 000 per mm 3 - Is important for blood clotting Blood clotting