Class Notes (865,678)
CA (523,035)
Humber (339)
BIOL (8)
BIOL 271 (7)
Matt (6)

WEEK 7- Lymphatic System.pdf

7 Pages

Course Code
BIOL 271

This preview shows pages 1 and half of page 2. Sign up to view the full 7 pages of the document.
Lymphatic System Lymphatic Circulation organs, vessels and a fluid called lymph similar to interstitial fluid colourless fluid with WBCs Organs red bone marrow thymus spleen lymph nodes diffuse lymphatic tissue tonsils, adenoids, Peyer's patches Functions drains excess interstitial fluid and plasma proteins from tissue spaces transports dietary lipids and lipid-soluble vitamins from GI tract to the blood facilitates immune responses recognizes and destroys microbes, toxins and abnormal cells by: direct attack (T-cells) secretion of Ab (B-cells & T-cells) Lymphatic Capillaries closed-ended tubes in spaces between cells found in all tissues except: avascular tissue (cartilage, epidermis, cornea) portions of spleen, red bone marrow tissue fluid enters through spaces between endothelial cells when interstitial pressure is high anchoring filaments prevent tube from collapsing under outside pressure Lacteals specialized lymphatic capillaries in villi of small intestine absorb dietary lipids (⇢creamy-white lymph called chyle) large nutrients cannot enter the cell except by specialized lymphatic capillaries Lymphatic Vessels and Circulation lymphatic capillaries combine to form lymphatic vessels resemble veins with thin walls, more valves flow through lymph nodes form plexuses (networks) around viscera lymph trunks: L. jugular trunk L. subclavian trunk L. lumbar trunk intestinal trunk vessels unite to form _______ lymph ducts: R. lymphatic duct drains lymph from R side of head and chest, and R arm to R subclavian v. thoracic duct drains lymph from rest of body to L subclavian c begins at ⊣ cistern chyli trunks drain to ducts Formation and Flow of Lymph fluid and proteins not returned to blood capillaries enters lymphatic capillaries, returns to the blood flow of lymph is promoted by respiratory pump and muscular pump Lymphatic Organs and Tissues primary lymphatic organs where stem cells divide and mature into B and T lymphocytes red bone marrow produces mature B cells thymus gland converts pre-T cells from red marrow into mature T-cells secondary lymphatic organs and tissues where most immune responses occur lymph nodes spleen lymphatic nodules diffuse lymphatic tissue not encapsulated found in CT of mucosa in GI, respiratory, urinary, reproductive tracts small amounts found in every organ of the body Thymus Gland lies over heart (in mediastinum between sternum and aorta) programs lymphocytes large in infants (70g), atrophies to about 3g in adults millions of T cells "trained" in infancy; then leave thymus, move to secondary organs 2 lobes, divided into lobules by extensions of capsule lobules consist of cortex and medulla cortex: large numbers of T-cells, scattered dendritic cells, important in immune response), epithelial cell
More Less
Unlock Document
Subscribers Only

Only pages 1 and half of page 2 are available for preview. Some parts have been intentionally blurred.

Unlock Document
Subscribers Only
You're Reading a Preview

Unlock to view full version

Unlock Document
Subscribers Only

Log In


Don't have an account?

Join OneClass

Access over 10 million pages of study
documents for 1.3 million courses.

Sign up

Join to view


By registering, I agree to the Terms and Privacy Policies
Already have an account?
Just a few more details

So we can recommend you notes for your school.

Reset Password

Please enter below the email address you registered with and we will send you a link to reset your password.

Add your courses

Get notes from the top students in your class.