Final Exam Study Guide AP III

Final Exam Study Guide AP III Essay questions to know  What are innate and adaptive immune systems, how they work and how they interact. Adaptive immunity is the ability of the body to defend itself against specific invading agents  Antigens are substances recognized as foreign that provoke immune responses Adaptive immunity has both specificity and memory and is divided into 2 types 1 Cell-mediated 2 Antibody-mediated In cell-mediated immunity:  An antigen is recognized and bound  A small number of T cells proliferate and differentiate into a clone of effector cells  The antigen is eliminated In antibody-mediated immunity:  An antigen is recognized and bound  Helper T cells costimulate the B cell so the B cell can proliferate and differentiate into a clone of effector cells that produce antibodies  The antigen is eliminated Innate immunity refers to a variety of body responses that serve to protect us against invasion of a wide variety of pathogens and their toxins.  We are born with this kind of immunity  Two lines of defense: Nonspecific disease resistance fight a wide variety of invaders. 1 st: Skin and mucous membranes: barriers, antimicrobial substances 2 nd: Internal defenses (cellular defenses), inflammation, and fever  Describe the anatomy and functions of the spleen. a. The spleen is the largest single mass of lymphatic tissue in the body. It is found in the left hypochondriac region between stomach and the diaphragm. It is composed of white pulp and red pulp. Red pulp filters blood and gets rid of old or damaged blood cells. White pulp consists of immune cells and helps fight infection. The spleen acts as a blood filter, if it detects bad bacteria, viruses in the blood, it and the lymph nodes create lymphocytes which act as defenders.  What is ventilation, external respiration and internal respiration. What are their functions and Location.  1. Pulmonary ventilation, or breathing, is the movement of air between the atmosphere and the lungs that occurs when we inhale and exhale  2. External respiration is the movement of oxygen from the alveoli into pulmonary capillaries and carbon dioxide from pulmonary capillaries to the alveoli.  3. Internal respiration is the movement of oxygen from capillaries into body cells and carbon dioxide from body cells into capillaries. Neural control of ventilation including brain centers, sensory and motor signals. Respiratory center- Neurons in the pons and medulla oblongata of the brain stem that regulate breathing. It is divided into the medullary respiratory center and the pontine respiratory center. Within the medullary respiratory center, you find two respiratory groups, the ventral respiratory group (AKA expiratory area) and the dorsal respiratory group (AKA inspiratory area). The DRG generates impulses to the diaphragm via the phrenic nerves and the external intercostals via the intercostal nerves. These impulses trigger contraction of these muscles which in turn execute inhalation. When the nerves are not firing, this passive relaxation allows recoil of the lungs and thoracic wall, passive exhalation. The VRG is only activated during forceful inhalation and trigger the accessory muscles to work. An important part of the VRG is the Pre-Botzinger Complex which is believed to be important in the generation of the rhythm of breathing (Pacemaker cells) Medulla oblongata receives signals & increases ventilation; pons controls rate of involuntary respiration; motor cortex; respiratory chemoreceptors Transport of oxygen and carbon dioxide are transported in the blood. How does loading/unloading of these gases take place in the lungs vs. tissues.  Dissolved in plasma (1.5%) (= blood PO2) Remember, O2 is not very soluble in blood! 2. Bound to hemoglobin in RBCs (98.5%)  The final step in the exchange of gases between the external environment and the tissues is the transport of oxygen and carbon dioxide to and from the lung by the blood. Oxygen is carried