Human Biology Lab 6 PDF

Human biology Lab 6………………………………………………………….…….Dr. Entethar A. Al-Araji & Moqtada Basim Immunity The term immunity refers to the general ability of a host to resist a particular infection or disease. There are two different types of immune responses: 1- The nonspecific immune response is also known a...

Human biology Lab 6………………………………………………………….…….Dr. Entethar A. Al-Araji & Moqtada Basim Immunity The term immunity refers to the general ability of a host to resist a particular infection or disease. There are two different types of immune responses: 1- The nonspecific immune response is also known as innate or natural immunity: it offers resistance to any microorganism or foreign material encountered by the vertebrate host. It includes general mechanisms inherited as part of the innate structure and function of each person (such as skin, mucus and acts as a first line of defense. The nonspecific immune response lacks immunological memory and nonspecific responses occur to the same extent each time a microorganism or foreign body is encountered. 2-The specific immune responses, also known as acquired, adaptive immunity: resist a particular foreign agent. The effectiveness of specific immune responses increases on repeated exposure to foreign agents such as viruses, bacteria, or toxins; that is to say, specific responses have “memory.” Substances that are recognized as foreign and provoke immune responses are called antigens. The antigens cause specific cells to replicate and manufacture a variety of proteins that function to protect the host. One such cell, the B cell, produces and secretes glycoproteins called antibodies. Antibodies bind to specific antigens and inactivate them or contribute to their elimination. Blood : is the fluid that circulates in the cardiovascular system , has many kind of chemicals dissolved in and million upon million of cells floating in it. The Functions of blood is Transport , Protection , Regulation Composition of blood Blood is classified as a connective tissue and consists of two main components A-Cellular elements blood cell, is a cell produced by hematopoiesis in bone marrow and is normally found in blood, the are : 1-Red blood cells (Erythrocytes) red color lacks nucleus oxygen transport cells have a life time of about 120 days. Women have about 4–5 and men about 5–6 million red blood cells per microliter (cubic millimeter) of blood 2-White blood cells (Leukocytes) Human biology Lab 6………………………………………………………….…….Dr. Entethar A. Al-Araji & Moqtada Basim colorless nucleated cells main function is defending the body against both infectious disease and foreign materials. 4,500 to 11,000 white blood cells per micro liter (mcL) average life of a WBC is generally 5 to 20 days. 3-Platelets (Thrombocytes) yellow blood cells, are very small, irregularly shaped clear cell fragments2–3 μm in diameter, The average life span of a platelet is normally just 5 to 9 days, prevent leakage or bleeding caused by vessel walls. range (150,000 to 450,000/mcL) B-Fluid Elements (plasma) Plasma is composed of : 1- Water 70% of body. 2- Electrolytes : (Na + , Ca++ ,K+ ,CL- ,H+.Mn++) 3-Proteins: coagulation protin(fibrinogen), Immuno protein (antibody) ,Transport proteins (Albumin,transferring) Difference in Definition: Serum is that part of blood which is similar in composition with plasma but exclude clotting factors of blood. Plasma is considered as the medium of blood in which RBCs, WBC and other components of blood are suspended. Blood smear Blood smears can be prepared from fresh whole blood without anticoagulant (fingertip or earlobe) or from the vein that collection with anticoagulant. A blood smear is a blood test used to look for the blood component, which include Red blood cells (RBC), White blood cells (WBC) and platelets. Tools & material: 1-Blood sample 2-Microscope 2- slide (2) 4-Lancets 5-Gloves 6-Leishman's stain 7- Distilled water 8-Marker for labeling 9-Sterilealcohol 10-Cotton. Procedure: 1.Place a small drop of blood close to the end of a slide. 2.Hold a second slide (spreader slide) on edge at a 30- to 45-degree angle and draw back into the blood drop, allowing it to spread along the edge of the spreader slide. 3.Quickly and steadily, push the spreader slide forward so that the blood spreads out into a thin film. Human biology Lab 6………………………………………………………….…….Dr. Entethar A. Al-Araji & Moqtada Basim 4.Let air-dry, fix and stain. 5-Pour the undiluted stain on to unfixed film and allow it to act for 2 min. 6-Using a pipette add double the volume of distilled water to the slide and allow the diluted stain to react for 12 min. 7-Wash off the stain with water. 6-Air-dry in a vertical position and examine under oil immersion lens in microscope.. The picture of blood under microscope