HUBS 192 Lecture Material PDF

HUBS 192 Lecture Material This pre-lecture material is to help you prepare for the lecture and to assist your note-taking within the lecture, it is NOT a substitute for the lecture ! Please note that although every effort is made to ensur...

HUBS 192 Lecture Material This pre-lecture material is to help you prepare for the lecture and to assist your note-taking within the lecture, it is NOT a substitute for the lecture ! Please note that although every effort is made to ensure this pre-lecture material corresponds to the live-lecture there may be differences / additions.  HUBS 192 Lecture 7 Cardiovascular System Circulatory System Anatomy Capillaries and Lymphatics Prof Greg Jones © The content and delivery of all resources in this course are copyrighted. This includes video and audio recordings, PowerPoints, lecture notes and handouts. You may access the materials provided for your private study or research but may not further distribute the materials for any purpose, or in any other form, whether with or without charge.  Quiz Questions What is the structure labelled 1 composed of; a. Endothelial cells b. Smooth muscle 1 c. Collagen d. Elastin 2 e. Laminin What cells are most common in the layer labelled 2? a. Endothelial cells b. Smooth muscle c. Skeletal muscle d. Fibroblasts  1 Objectives After you have revised this lecture you should be able to: Describe the structure of blood capillaries and contrast it with that of arteries and veins. Describe, giving examples, the three different types of blood capillaries. Name the major components of the lymph vascular system. Describe the structure of lymph capillaries.  2 Readings from Martini et al., Visual Anatomy and Physiology (3rd ed) Capillaries: Module 19.3 (pages 742-743) Lymphatic system: Module 20.1 (page 793), Module 20.2 (page 794-795), Module 20.5, point 3, lymph nodes (page 801)  3 Capillaries Function: Site of exchange between blood and tissues. This function demands: i) Very thin walls. ii) Large total cross sectional area of capillary bed. iii) Slow & smooth blood flow. Large total area of the capillary bed (compared to arterioles) means much slower blood flow.  4 Histological Structure: Capillary Anatomy teaching resources 2011  Ultrastructure: Capillary 5 RBC Intercellular junctions Anatomy teaching resources 2011  6 Vascular shunt Precapillary sphincters Metarteriole Thoroughfare channel Terminal arteriole Postcapillary venule Precapillary sphincters are composed of smooth muscle cells © 2016 Pearson Education, Inc.  7 Capillary, Structure The structure of capillaries varies according to the rate of exchange needed, and how controlled the exchange must be. Three types: A) Continuous capillaries (the most widespread). B) Fenestrated capillaries (leaky). C) Sinusoidal capillaries (very leaky).  Continuous Capillary 8 8-10µm diameter eg. Skeletal and Cardiac Muscle By OpenStax College - Anatomy & Physiology via Wikimedia Commons  Glomerulus, Kidney 9 Fenestrated Capillary 8-10µm diameter Anatomy teaching resources 2011 By OpenStax College - Anatomy & Physiology  Fenestrated Capillary (small intestine) 10 Anatomy teaching resources 2011  11 Scanning EM Stanley & Magney, Color Atlas of Histology. Transmission EM Mosby Year Book Publishing 1992, Figure 10-22  12 Sinusoidal Capillary Liver Sinusoids 30-40µm diameter Mosby Year Book Publishing 1992, Figure 10-22 Stanley & Magney, Color Atlas of Histology. By OpenStax College - Anatomy & Physiology  11 1.Continuous X 2. Fenestrated 3. Sinusoidal  13 Continuous 1,2,4 Fenestrated 1,2,3,4 Sinusoidal1,2,3,4 © 2016 Pearson Education, Inc. Blood and Lymph Vascular Systems 14  15 Lymph Vascular System An open-entry (drainage) system. Functions: 1. Drains excess tissue fluid & plasma proteins from tissues and returns them the blood. 2. Filters foreign material from the lymph. 3. ‘Screens’ lymph for foreign antigens & responds by releasing antibodies & activated immune cells. 4. Absorbs fat from intestine and transports to blood.  16 The Lymphatic System Structure Lymphatic vessels 1. Commence as large, blind ending capillaries. 2. From small intestine, a special group of lymphatic vessels called lacteals drain fat-laden lymph into a collecting vessel called the cisterna chyli. 3. Larger (thin wall) collecting vessels have numerous valves to prevent backflow.  The Lymph Vascular System 17 © 2018 Pearson Education, Ltd. Figure 20.2 1 2  18 Veins Artery Lymph channel Lymph vessels Thin walled No RBC’s Valves © 2018 Pearson Education, Ltd. Figure 20.2 3 – 4  Regional lymph nodes 19 Marieb, Human Anatomy & Physiology 4th Ed. Benjamin Cummings Publishing Figure 21.2  20 Small Intestine villus Lacteal To the portal vein from the intestinal arteries Stanley & Magney, Color Atlas of Histology. Mosby Year Book Publishing 1992 Figure 15-16 Regional lymph nodes 21 Marieb, Human Anatomy & Physiology 4th Ed. Benjamin Cummings Publishing Figure 21.2  22 Lymph Node Structure Afferent lymphatics Efferent lymphatic Figure 20.5 3 © 2018 Pearson Education, Ltd.  23 Lymphatic Drainage of the Breast Right lymphatic duct Right subclavian vein Breast tissue lymphatic Axillary lymph drainage can carry cancer cells nodes into the blood vascular system…Metastatic cancer Lymphatic vessels of the breast Saladin, Anatomy & Physiology 3rd Ed. McGraw Hill Figure 21.6  HUBS192 Copyright Warning Notice This coursepack may be used only for the University’s educational purposes. It includes extracts of copyright works copied under copyright licences. You may not copy or distribute any part of this coursepack to any other person. Where this coursepack is provided to you in electronic format you may only print from it for your own use. You may not make a further copy for any other purpose. Failure to comply with the terms of this warning may expose you to legal action for copyright infringement and/or disciplinary action by the University