1. 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

2. 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

3. 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

4. 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

5. 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

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

7. 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

8. 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.

9. 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

10. Drainage
Lymphatic trunks is where drainage occurs

11. 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

12. 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?

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

14. 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

15. 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

16. 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

17. 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

18. 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

19. 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

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

21. 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

22. 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