1A. What you will draw
The lymphatic system both drains tissue fluid and houses the first line of immune defense. Today you'll draw the major lymphatic structures across the body, then a close-up of an inflammatory response in a tissue.
BIO 304 . WEEK 7 . MONDAY . LAB WORKBOOK
Lymphatic System and Innate Immunity
Lymph nodes, vessels, spleen, thymus; barriers, phagocytes, NK cells, inflammation, complement, fever.
Print this page. You will draw your own diagrams from the directions below, then hand-label the structures listed. Drawing by hand is the integrity mechanism for this course.
Part 1 of 2
Anatomy Lab
Box A. Major lymphatic structures
Directions
- Draw a simple body outline.
- Lymph nodes: cluster small ovals at the cervical (neck), axillary (armpit), and inguinal (groin) regions. Label each cluster.
- Thymus: in the upper chest behind the sternum. Label (note: large in childhood, atrophies with age).
- Spleen: in the upper left abdomen, behind the stomach. Label.
- MALT (mucosa-associated lymphoid tissue): mark tonsils in the throat, Peyer's patches in the small intestine, and appendix. Label.
- Draw a network of lymphatic vessels running through the body, with two large terminal ducts emptying into veins near the heart: thoracic duct (drains most of the body, empties into the left subclavian vein) and right lymphatic duct (drains right upper body, empties into the right subclavian vein). Label.
Draw here. Sketch by hand.
Box B. Acute inflammation in a tissue
Directions
- Draw a section of tissue with a small injury (e.g., a splinter introducing bacteria).
- Show a nearby blood capillary. Add arrows pointing OUT from the capillary indicating vasodilation and increased permeability.
- Show fluid leaking from the capillary into the tissue, causing edema (swelling). Label.
- Draw neutrophils squeezing through the capillary wall (diapedesis or extravasation) and migrating toward the bacteria. Label.
- Draw the neutrophils phagocytosing bacteria. Label.
- Mark the four cardinal signs of inflammation around the site: redness (rubor), heat (calor), swelling (tumor), pain (dolor). Add Latin names if you want.
Draw here. Sketch by hand.
1C. Structures to label (22)
After you finish each drawing, label every structure below directly on your sketch.
- Lymph node
- Cervical nodes
- Axillary nodes
- Inguinal nodes
- Thymus
- Spleen
- Tonsils
- Peyer's patches
- Appendix
- Lymphatic vessel
- Thoracic duct
- Right lymphatic duct
- Vasodilation
- Increased permeability
- Edema
- Neutrophil
- Diapedesis (extravasation)
- Phagocytosis
- Redness
- Heat
- Swelling
- Pain
Part 2 of 2
Physiology Lab
2A. Innate defense table
Fill in the table classifying innate immune defenses by category. After the table, answer the two follow-up questions.
| Category | Example | Mechanism of defense |
|---|---|---|
| Physical barrier | Skin | |
| Chemical barrier | Stomach acid (low pH) | |
| Phagocyte | Neutrophil | |
| Phagocyte | Macrophage | |
| Cytotoxic innate cell | Natural killer (NK) cell | |
| Chemical mediator | Complement | |
| Whole-body response | Fever | |
| Local response | Inflammation |
Fever is a regulated rise in body temperature in response to infection. Explain mechanistically why a moderate fever is BENEFICIAL during a bacterial infection. Why is very high fever (over 41 C) dangerous?
Complement is a cascade of plasma proteins that can punch holes in bacterial membranes. Explain the term 'cascade' in this context, and how this design lets a small initial signal produce a large response.
2B. Synthesis questions
Answer each in 2 to 4 sentences. Use the language from this week's lecture and your drawings as evidence.
1. A patient has a breast tumor removed along with several axillary lymph nodes. Predict the long-term consequence in the arm on that side, and explain mechanistically why this complication occurs (lymphedema).
2. A patient is taking corticosteroids long-term and develops infections easily. Explain mechanistically how corticosteroids suppress the innate immune response (consider phagocyte activity, inflammation, fever response).
3. Compare innate and adaptive immunity in one paragraph: speed of response, specificity, memory, and which cells are involved. Why does the body need BOTH systems?
3. What to submit
Complete both the Anatomy Lab (your own drawings, hand-labeled, plus the structures list) and the Physiology Lab (activity and synthesis questions). Photograph or scan every page and upload to Canvas before the deadline listed on the schedule. Hand-drawn, hand-labeled work is the integrity mechanism for this course. Typed or AI-generated diagrams are not accepted.