Do Now Using your previous knowledge, how does our body prevent infection? How does our body fight off infection? Copyright © Houghton Mifflin Harcourt Publishing Company 1

Chapter 12 - Lesson 1 The Lymphatic System SLO: You should be able to explain the 2 primary functions of the lymphatic system an how these two processes work together to help keep the body healthy. Essential Question: What would happen to the body if it did not have a lymphatic system? Copyright © Houghton Mifflin Harcourt Publishing Company 2

Vocabulary Lymph MALT Lymph nodes Interstitial fluid Lymphatic vessels mucosa associated lymphatic tissue Interstitial fluid Natural killer (NK) cells Lymphatic vessels Pathogens Lymphocytes Lingual tonsils B lymphocytes Palatine tonsils T lymphocytes Pharyngeal tonsils Endothelial cells Spleen Macrophages Thymus Copyright © Houghton Mifflin Harcourt Publishing Company 3

Anticipatory Set Your body is constantly fighting off potential invaders...disease-producing microbes at the microscopic level. We are going to investigate how this process happens despite our awareness. Copyright © Houghton Mifflin Harcourt Publishing Company 4

The lymphatic system provides another type of circulation in the body. 2 functions: Collects/reabsorbs fluid that leaks from the circulatory system and returns it Helps to mount counter attack against infectious agents/assist the immune system

Agenda Organization of the lymphatic system lymph formation and flow lymph drainage Lymphatic cells, tissues, and organs lymphatic cells lymphatic tissues lymphatic organs

Lymphatic Fluid = Lymph fluid leaks out of blood vessel capillaries about 4 liters per day blood plasma Fluid leaks out into the spaces between the cells Interstitial fluid Fluid enters the lymphatic capillaries Lymph gaps between endothelial cells Endothelial cells form the walls of all capillaries

Lymph fluid that flows throughout the system through lymph vessels Lymph vessels extend throughout the body and return cleaned lymph fluid to the circulatory system.

Collection/Absorption and Drainage Lymphatic capillaries collecting vessels lymphatic trunks lymphatic ducts thoracic duct drains legs, abdominopelvic area, left arm, and left side of the head and thorax right lymphatic duct drains right arm, right side of head, and right side of the thorax one directional of flow Valves Muscle contractions/ movement of organs Lymphatic trunks is where drainage occurs

Drainage Lymphatic trunks is where drainage occurs

Do Now: Match these words with 1–2 below: right lymphatic duct, thoracic duct 1. drains left side of head 2. drains right side of head

Checking for understanding. What would happen if lymph vessels were damaged? What would happen if all the fluid collected is not returned to the circulatory system?

Independent Practice: “Check your Understanding” Questions p415 (10 mins)

Lymphatic Cells, Tissues, and Organs Lymph cells - lymphocytes, destroy infection Lymph organs Lymph nodes Spleen Thymus Lymph tissue - loose connective tissue ie. tonsils Lymph nodes and tissues surround vessels along the body Lymphatic trunks is where drainage occurs

Lymphatic Cells/Lymphocytes macrophage abundant in lymphatic tissue, nodes, organs B lymphocytes Produce antibodies that tag pathogens mature in bone marrow T lymphocytes Once activated they divide rapidly and secrete cytokines Mature in thymus Natural Killer cells Destroy cancer cells and virus-infected cells Macrophages Phagocytize foreign objects/pathogens/old blood leave lymphatic tissue to enter surrounding tissue

3. Destroy cancer cells and virus-infected cells Do Now: Match these words with 1–4 below: T cell, B cell, NK cell, Macrophage. Produce antibodies that tag pathogens Mature in thymus 3. Destroy cancer cells and virus-infected cells 4. Phagocytize foreign objects/pathogens/old blood Slide where 12C left off

Lymphatic Tissue Mucosa-associated lymphatic tissue (MALT)- lines the tracts of different organs/pharynx Palatine tonsils Pharyngeal (adenoids) tonsils Lingual tonsils tonsils filter bacteria and viruses

Lymphatic Organs Lymph nodes Filter lymph trap bacteria/harmful substances Store T cells/B cells that await ambush -- Alert an immune response, lymphocytes multiply and lymph nodes enlarge

Lymphatic organs Spleen Largest blood supply Filters blood and activates the immune system White pulp-rich in lymphocytes Red pulp-destroys old red blood cells

Lymphatic organs Thymus Largest during child hood, shrinks steadily afterwards thymus completes maturity of T cells

Exit Slip Homework Study for Vocabulary Test-Lesson 12.1 What 2 purposes does the lymphatic system serve? How does lymphatic fluid drain into the circulatory system? Where are lymphatic tissues found in the body? What is the responsibility of the lymph nodes? Homework Study for Vocabulary Test-Lesson 12.1 Copyright © Houghton Mifflin Harcourt Publishing Company 21

Exit Slip Homework Read & Outline Lesson 12.1 What 2 purposes does the lymphatic system serve? How does lymphatic fluid drain into the circulatory system? Where are lymphatic tissues found in the body? What is the responsibility of the lymph nodes? Homework Read & Outline Lesson 12.1 Complete online/textbook assessment (1-9: Know/Understand/Analyze/Apply) Copyright © Houghton Mifflin Harcourt Publishing Company 22