BIOL 320 1 st Edition Lecture 10 Outline of Last Lecture I Capillary Modifications II Venules Veins III Hemodynamics IV Blood Flow Long Term Auto regulation of Blood Flow Blood Flow Skeletal Muscles Blood Flow Brain V Blood Pressure VI Venous Return VII Blood Pressure Regulation Cardiac Output Regulation by BP Short Term BP Controls VMC Regulation Baroreceptor Reflex Long Term BP Regulation Renal Outline of Current Lecture VIII Regulation of MAP IX Extrinsic Factors Affecting BP X Homeostatic Imbalances for BP Hypotension Hypertension XI Circulatory Shock Definition Result Types XII Vascular Disorders Atherosclerosis Arteriosclerosis XIII Developmental Aspects Formed from Fetal Shunts Umbilical Veins Arteries Vessel Formation Aging I Lymphatic System a Functions b Lymph Fluid Formation c Volume II Lymphatic Vessels a Lymph Capillaries b Endothelial Lining c Collects d Collecting Vessels III Lymphatic Drainage a Pathway b Transport IV Lymphatic Collecting Vessels a Characteristics b Transport c Acquire Nutrients V Lymph Transport REVIEW VI Lymphoid Cells a Macrophages b Lymphocytes i Functions ii Types VII Lymphoid Tissues a Lymph Nodes i Regional Concentrations ii Function iii Primary Cell Type iv Characteristics Current Lecture Regulation of MAP Extrinsic Factors Affecting BP Age Sex Weight Race Mood Posture Socioeconomic status maybe due to diet Physical Activity Homeostatic Imbalances for BP Hypotension o Orthostatic temporary decline in BP o Chronic consistently low BP usually related to poor nutrition sign possibly of Addison s Disease low production of mineralocorticoids and glucocorticoids and Hyperthyroidism o Acute rapid change decrease in BP sign of circulatory shock Hypertension o Transient normal caused by fever physical exertion and emotional upset o Chronic damage to vessels baroreceptors heart muscle vascular organs Primary essential risk factors include those above heredity stress smoking Major cause of heart failure vascular disease renal failure stroke Secondary due to other disorders Circulatory Shock Definition blood volume is low so can t circulate normally Result inadequate blood flow and can t meet tissue needs Types o Hypovolemic shock large blood loss sever vomiting severe diarrhea o Vascular shock extreme vasodilation WHY not enough blood to circulate evenly to tissues o Cardiogenic shock poor heart function heart caused heart cannot sustain circulation o Obstructive shock blockage of blood flow o Anaphylactic shock due to massive histamine release due to severe allergic reactions histamine causes vasodilation causes vascular shock Vascular Disorders Atherosclerosis o Deposit lipid plaques on walls o Result increased peripheral resistance increases BP harder for heart to circulate dramatic increased turbulence BP o Increased risk heart attack stroke thrombi emboli Arteriosclerosis o Family of degenerative diseases disorders where arteries arteriole become calcified resulting in decreased elasticity Developmental Aspects Endothelial lining develops from the mesoderm germ layer Fetal Shunts o Foramen ovale pulmonary circulation bypass during development in the womb becomes fossa ovale o Ductus arteriosus bypasses fluid filled non functioning lungs during development in the womb o Ductus venosus liver bypass during development in the womb Umbilical Veins and Arteries o Functions gas exchange for developing baby in the womb Vessel Formation o Occurs As needed Wound healing Uterine every month of menstrual cycle Aging o High blood pressure o Atherosclerosis o Varicose veins Lymphatic System Functions o Fat absorption o Immunity lymphocytes travel within it o Fluid balance recapture bruising for example Lymph Fluid Formation o Fluid that has leaked out of the bloodstream fenestrated capillaries especially Volume o 1 5 ml min or 2 1 L day o 43 of circulating blood volume o Circulates at low pressure Lymphatic Vessels Lymph Capillaries collect lymph in all tissues one way path to heart Endothelial Lining very loose leaky increased tissue pressure opens flaps to allow lymph to enter if pressure is equal between tissue space and lymph capillary flaps remain closed Collects o Fluid plasma o Cells o Waste material o Proteins Collecting Vessels similar to veins convergence of lymph capillaries Lymphatic Drainage Pathway o Lymph capillaries Collecting vessels Lymph nodes Trunks Ducts Subclavian veins Transport o No central pump o Pressure changes due to Activity of smooth muscle Activity of skeletal muscle Breathing Lymphatic Collecting Vessels Characteristics o Similar to veins except Thinner walls more internal valves Anastomose more frequently Transport o In skin collecting vessels travel with superficial veins o Deep vessels travel with arteries Acquire Nutrients o Nutrients supplied from branching vas vasorum Lymph Transport REVIEW No central pump Lymph pressurized by o Tissue pressure o Smooth muscle activity o Skeletal muscle activity o Breathing o Arteries Lymph flow matches tissue activity Valves ensure one way flow Lymphoid Cells Macrophages big eaters different from monocytes engulf trash debris microbes damaged cells Lymphocytes o Functions Protect body from foreign antigens Some mature into attack cells o Types T Lymphocytes activated in thymus gland direct immune response B Lymphocytes activated in bone marrow produce plasma cells that secrete anti bodies Lymphoid Tissues Lymph Nodes o Regional Concentrations Axillary Inguinal Cervical o Function Filter lymph o Primary Cell Type Macrophage o Characteristics More afferent than efferent vessels Become enlarged during infection Cancer spreads metastasizes via lymphatic system