ch. 20 lymphatic system

lymph vessels have:

lymphatic vessels —→ lymphatic capillaries ——→ collecting lympathic vessels ——> lymphatic trunks and ducts

lymphatic capillaries

permeable to let stuff in and if it’s bad and WBC kill

minivalves: put more pressure on the ECF opens the minivlaves

ptahogens travel thru the body thru lymphatics

not in places with fluid like teeth, bone marrow, and CNS

lymphatic collecting vessels

more internal valves

anastomoses: connected vessels that branch off and eventually merge tg ——> happens when one breaks so theres a back up(bypass)

lymphatic trunk

where the lymphstic vessels go to

lymphatic ducts

split in 2:

right : right arm, right side head

thoracic: rest of the body

where do the lymphatic ducts empty lymph

into venous circulation at subclavian vein and go into heart

lymphoid organs

spleen, thymus, tonsils, lymph nodes, and other tissues

lymphoid cells

lymphocytes T and B cells

T cells

attack destroy infected cells

B cells

mark body for antgens adn to destruct thru pahgocytosis and the T cell

macrophages

phagocytize foreign and help activate t cells

dendritic cells

capture antigens and bring them to the lymph nodes

actually activate t cells

reticular cells

reituclar fiber fiber stroma that attacks

lymphoid tissue is primarily made out of

reticular connective tissue

lymphoid follicles (nodules)

solid spherical bodies with tightly packed lymphoid cells + reticular fibers

inside are germinal center

germinal center

b proliferating site

where t lymphocytes are made

deep cortex

lymph node function

filter lymph destroy foreign

lymphocytes are activated

circulation of the lymph node

afferent lymphatic vessels —→ travels thru subscapular sinus —→ exits at hilum

spleen

lymphocyte proliferation

cleans old blood cells and platelets and macrophages

stores borken down RBC

which lymphoid rogan contributes to fetal erythrocyte production

the spleen

white pulp in the spleen

WBC

sick

red pulp

RBC

destroys pathogens and worn out RBC

thymus

T cell development

thymus cortex

freshman/soph: many will fail not make it

thymus medulla

jr/sr: medulla mature T cells who have passed (small number)

what kind of stroma does the thymus have and why

epithelial bc theres not a blood filter or lymph ——> keep unprepped WBC protected and not get pahtogens too early

know MALT (where), tonsils and peyer patches